diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 0000000..e07b932
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,78 @@
+version: 1.6.x-{build}
+
+branches:
+  except:
+    - /libpng[0-1][0-7]/
+
+image:
+  - Visual Studio 2022
+
+shallow_clone: true
+
+environment:
+  matrix:
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: x86
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: x64
+    - TOOLCHAIN: vstudio
+      AUTOMATION: cmake
+      ARCH: arm64
+    - TOOLCHAIN: llvm
+      AUTOMATION: cmake
+      ARCH: x64
+    - TOOLCHAIN: msys2
+      AUTOMATION: cmake
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: cmake
+      ARCH: x86_64
+    - TOOLCHAIN: msys2
+      AUTOMATION: configure
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: configure
+      ARCH: x86_64
+    - TOOLCHAIN: msys2
+      AUTOMATION: makefiles
+      ARCH: i686
+    - TOOLCHAIN: msys2
+      AUTOMATION: makefiles
+      ARCH: x86_64
+
+install:
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe integrate install'
+  - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
+  - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe integrate install'
+
+before_build:
+  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_GENERATOR=Visual Studio 17 2022'
+  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x86" set CI_CMAKE_GENERATOR_PLATFORM=Win32'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x64" set CI_CMAKE_GENERATOR_PLATFORM=x64'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_GENERATOR_PLATFORM=ARM64'
+  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_VARS=-DPNG_TESTS=0'
+  - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_GENERATOR=Ninja'
+  - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
+  - 'if "%TOOLCHAIN%"=="llvm" set CI_CC=clang.exe'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" set CI_CMAKE_GENERATOR=Unix Makefiles'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="i686" set PATH=C:\msys64\mingw32\bin;%PATH%'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="x86_64" set PATH=C:\msys64\mingw64\bin;%PATH%'
+  - 'if "%TOOLCHAIN%"=="msys2" set CI_CC=%ARCH%-w64-mingw32-gcc.exe'
+  - 'set CI_CMAKE_BUILD_FLAGS=-j2'
+  - 'set CI_CTEST_FLAGS=-j2'
+  - 'set CI_MAKE_FLAGS=-j2'
+  - 'set CI_MAKEFILES=scripts/makefile.gcc scripts/makefile.msys scripts/makefile.std'
+
+build_script:
+  - 'if "%TOOLCHAIN%"=="vstudio" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
+  - 'if "%TOOLCHAIN%"=="llvm" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="configure" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_configure.sh"'
+  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="makefiles" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_makefiles.sh"'
+
+cache:
+  - C:\tools\vcpkg\installed
diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..34a145d
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,38 @@
+# https://editorconfig.org
+
+root = true
+
+[*]
+charset = utf-8
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+# Traditionally, the end-of-line character has been platform-specific.
+end_of_line = unset
+
+[*.[chS]]
+indent_style = space
+max_line_length = 81
+
+[*.{awk,cmake,dfa,in,sh}]
+indent_style = space
+max_line_length = 100
+
+[*.txt]
+indent_style = space
+max_line_length = unset
+
+[{Makefile.in,ltmain.sh}]
+indent_style = unset
+insert_final_newline = unset
+max_line_length = unset
+trim_trailing_whitespace = unset
+
+[*~]
+indent_style = unset
+insert_final_newline = unset
+max_line_length = unset
+trim_trailing_whitespace = unset
+
+[COMMIT_EDITMSG]
+max_line_length = 72
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..52e789d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,79 @@
+# Prerequisites
+*.d
+
+# Precompiled headers
+*.gch
+*.pch
+
+# Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Linker output files
+*.exp
+*.ilk
+*.map
+
+# Compiled dynamic libraries
+*.dll
+*.dylib
+*.so
+*.so.*
+
+# Compiled static libraries
+*.a
+*.la
+*.lai
+*.lib
+
+# Compiled executables
+*.app/
+*.exe
+
+# Debug files
+*.dSYM/
+*.idb
+*.pdb
+*.su
+
+# Libpng configuration and build artifacts
+*.out
+.deps/
+.dirstamp
+/Makefile
+/autom4te.cache/
+/config.guess~
+/config.h.in~
+/config.log
+/config.status
+/config.sub~
+/configure~
+/install-sh~
+/libpng-config
+/libpng.pc
+/libpng.vers
+/libpng16-config
+/libpng16.pc
+/libtool
+/stamp-h1
+pnglibconf.[ch]
+pnglibconf.dfn
+pnglibconf.pre
+pngprefix.h
+
+# Libpng test artifacts
+png-fix-itxt
+pngcp
+pngfix
+pngimage
+pngstest
+pngtest
+pngunknown
+pngvalid
+timepng
+pngout.png
+
+# Libpng CI artifacts
+out/
diff --git a/.travis.yml b/.travis.yml
index 2a931b6..ab3fba6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,23 +1,33 @@
+branches:
+  except:
+    - /libpng[0-1][0-7]/
+
 language: c
 
-compiler:
-  - clang
-
-env:
-  - USE_CMAKE=1 DISABLE_TESTS=1
-  - USE_CMAKE=1 ENABLE_SANITIZERS="address,undefined" EXTRA_ARGS="-DPNG_HARDWARE_OPTIMIZATIONS=ON"
-  - USE_CMAKE=1 ENABLE_SANITIZERS="address,undefined" EXTRA_ARGS="-DPNG_HARDWARE_OPTIMIZATIONS=OFF"
-  - USE_CONFIGURE=1 DISABLE_TESTS=1
-  - USE_CONFIGURE=1 EXTRA_ARGS="--enable-hardware-optimizations"
-  - USE_CONFIGURE=1 EXTRA_ARGS="--disable-hardware-optimizations"
-  - USE_LEGACY_MAKEFILES=1 DISABLE_TESTS=1
-  - USE_LEGACY_MAKEFILES=1 ENABLE_SANITIZERS="address,undefined"
-
 os:
+  - freebsd
   - linux
   - osx
 
-script:
-  - bash ./scripts/travis.sh
+env:
+  - AUTOMATION=cmake CI_CMAKE_VARS="-DPNG_HARDWARE_OPTIMIZATIONS=ON"
+  - AUTOMATION=cmake CI_CMAKE_VARS="-DPNG_HARDWARE_OPTIMIZATIONS=OFF"
+  - AUTOMATION=configure CI_CONFIGURE_FLAGS="--enable-hardware-optimizations"
+  - AUTOMATION=configure CI_CONFIGURE_FLAGS="--disable-hardware-optimizations"
+  - AUTOMATION=makefiles
 
-sudo: false
+matrix:
+  include:
+    - os: osx
+      env: AUTOMATION=cmake CI_CMAKE_GENERATOR=Xcode
+
+before_script:
+  - 'if test "$TRAVIS_OS_NAME" = "linux"; then export CI_CC="gcc"; else export CI_CC="clang"; fi'
+  - 'if test "$TRAVIS_OS_NAME" != "osx"; then export CI_SANITIZERS="address,undefined"; fi'
+  - 'export CI_MAKEFILES="scripts/makefile.$CI_CC scripts/makefile.std"'
+  - 'export CI_MAKE_FLAGS=-j2'
+  - 'export CI_CMAKE_BUILD_FLAGS=-j2'
+  - 'export CI_CTEST_FLAGS=-j2'
+
+script:
+  - './ci/ci_verify_$AUTOMATION.sh'
diff --git a/.yamllint.yml b/.yamllint.yml
new file mode 100644
index 0000000..3829416
--- /dev/null
+++ b/.yamllint.yml
@@ -0,0 +1,5 @@
+extends: default
+rules:
+  document-start: disable
+  document-end: disable
+  line-length: disable
diff --git a/ANNOUNCE b/ANNOUNCE
index 83bf76e..2e749c3 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,4 +1,4 @@
-libpng 1.6.38.git
+libpng 1.6.43.git
 =================
 
 This is a development version, not intended to be a public release.
@@ -6,8 +6,8 @@
 version, at a later time.
 
 
-libpng 1.6.37 - April 14, 2019
-==============================
+libpng 1.6.42 - January 29, 2024
+================================
 
 This is a public release of libpng, intended for use in production code.
 
@@ -17,13 +17,13 @@
 
 Source files with LF line endings (for Unix/Linux):
 
- * libpng-1.6.37.tar.xz (LZMA-compressed, recommended)
- * libpng-1.6.37.tar.gz
+ * libpng-1.6.42.tar.xz (LZMA-compressed, recommended)
+ * libpng-1.6.42.tar.gz (deflate-compressed)
 
 Source files with CRLF line endings (for Windows):
 
- * lp1637.7z (LZMA-compressed, recommended)
- * lp1637.zip
+ * lpng1642.7z (LZMA-compressed, recommended)
+ * lpng1642.zip (deflate-compressed)
 
 Other information:
 
@@ -33,20 +33,47 @@
  * TRADEMARK.md
 
 
-Changes since the previous public release (version 1.6.36)
-----------------------------------------------------------
+Changes from version 1.6.41 to version 1.6.42
+---------------------------------------------
 
- * Fixed a use-after-free vulnerability (CVE-2019-7317) in png_image_free.
- * Fixed a memory leak in the ARM NEON implementation of png_do_expand_palette.
- * Fixed a memory leak in pngtest.c.
- * Fixed two vulnerabilities (CVE-2018-14048, CVE-2018-14550) in
-   contrib/pngminus; refactor.
- * Changed the license of contrib/pngminus to MIT; refresh makefile and docs.
-   (Contributed by Willem van Schaik)
- * Fixed a typo in the libpng license v2.
-   (Contributed by Miguel Ojeda)
- * Added makefiles for AddressSanitizer-enabled builds.
- * Cleaned up various makefiles.
+ * Fixed the implementation of the macro function `png_check_sig`.
+   This was an API regression, introduced in libpng-1.6.41.
+   (Reported by Matthieu Darbois)
+
+
+Changes from version 1.6.40 to version 1.6.41
+---------------------------------------------
+
+ * Added SIMD-optimized code for the Loongarch LSX hardware.
+   (Contributed by GuXiWei, JinBo and ZhangLixia)
+ * Fixed the run-time discovery of MIPS MSA hardware.
+   (Contributed by Sui Jingfeng)
+ * Fixed an off-by-one error in the function `png_do_check_palette_indexes`,
+   which failed to recognize errors that might have existed in the first
+   column of a broken palette-encoded image. This was a benign regression
+   accidentally introduced in libpng-1.6.33. No pixel was harmed.
+   (Contributed by Adam Richter; reviewed by John Bowler)
+ * Fixed, improved and modernized the contrib/pngminus programs, i.e.,
+   png2pnm.c and pnm2png.c
+ * Removed old and peculiar portability hacks that were meant to silence
+   warnings issued by gcc version 7.1 alone.
+   (Contributed by John Bowler)
+ * Fixed and modernized the CMake file, and raised the minimum required
+   CMake version from 3.1 to 3.6.
+   (Contributed by Clinton Ingram, Timothy Lyanguzov, Tyler Kropp, et al.)
+ * Allowed the configure script to disable the building of auxiliary tools
+   and tests, thus catching up with the CMake file.
+   (Contributed by Carlo Bramini)
+ * Fixed a build issue on Mac.
+   (Contributed by Zixu Wang)
+ * Moved the Autoconf macro files to scripts/autoconf.
+ * Moved the CMake files (except for the main CMakeLists.txt) to
+   scripts/cmake and moved the list of their contributing authors to
+   scripts/cmake/AUTHORS.md
+ * Updated the CI configurations and scripts.
+ * Relicensed the CI scripts to the MIT License.
+ * Improved the test coverage.
+   (Contributed by John Bowler)
 
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
diff --git a/AUTHORS b/AUTHORS
index 79a3d10..5443416 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -4,7 +4,9 @@
 This is the list of PNG Reference Library ("libpng") Contributing
 Authors, for copyright and licensing purposes.
 
+ * Adam Richter
  * Andreas Dilger
+ * Chris Blume
  * Cosmin Truta
  * Dave Martindale
  * Eric S. Raymond
@@ -20,7 +22,10 @@
  * Mans Rullgard
  * Matt Sarett
  * Mike Klein
+ * Pascal Massimino
  * Paul Schmidt
+ * Philippe Antoine
+ * Qiang Zhou
  * Sam Bushell
  * Samuel Williams
  * Simon-Pierre Cadieux
@@ -30,16 +35,27 @@
  * Vadim Barkov
  * Willem van Schaik
  * Zhijie Liang
+ * Apple Inc.
+    - Zixu Wang (王子旭)
  * Arm Holdings
-   - Richard Townsend
+    - Richard Townsend
  * Google Inc.
-   - Matt Sarett
-   - Mike Klein
+    - Dan Field
+    - Leon Scroggins III
+    - Matt Sarett
+    - Mike Klein
+    - Sami Boukortt
+    - Wan-Teh Chang
+ * Loongson Technology Corporation Ltd.
+    - GuXiWei (顾希伟)
+    - JinBo (金波)
+    - ZhangLixia (张利霞)
 
 The build projects, the build scripts, the test scripts, and other
-files in the "projects", "scripts" and "tests" directories, have other
-copyright owners, but are released under the libpng license.
+files in the "projects", "scripts" and "tests" directories, have
+other copyright owners, but are released under the libpng license.
 
-Some files in the "contrib" directory, and some tools-generated files
-that are distributed with libpng, have other copyright owners, and are
-released under other open source licenses.
+Some files in the "ci" and "contrib" directories, as well as some
+of the tools-generated files that are distributed with libpng, have
+other copyright owners, and are released under other open source
+licenses.
diff --git a/CHANGES b/CHANGES
index 01deeef..478b63a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -204,7 +204,7 @@
   Added simple sRGB support (Glenn R-P)
   Easier conditional compiling, e.g.,
     define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
-    all configurable options can be selected from command-line instead
+    all configurable options can be selected from command line instead
     of having to edit pngconf.h (Glenn R-P)
   Fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
   Added more conditions for png_do_background, to avoid changing
@@ -942,7 +942,7 @@
 Version 1.0.9beta1 [November 10, 2000]
   Fixed typo in scripts/makefile.hpux
   Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser)
-  Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
+  Fixed sequence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
   Changed "cdrom.com" in documentation to "libpng.org"
   Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg).
   Changed type of "params" from voidp to png_voidp in png_read|write_png().
@@ -2295,7 +2295,7 @@
   Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri)
 
 Version 1.4.0beta59 [May 15, 2009]
-  Reformated sources in libpng style (3-space intentation, comment format)
+  Reformatted sources in libpng style (3-space indentation, comment format)
   Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG)
   Added sections about the git repository and our coding style to the
     documentation
@@ -2661,7 +2661,7 @@
 
 Version 1.4.1beta07 [February 6, 2010]
   Folded some long lines in the source files.
-  Added defineable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
+  Added definable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
     and a PNG_USER_LIMITS_SUPPORTED flag.
   Eliminated use of png_ptr->irowbytes and reused the slot in png_ptr as
     png_ptr->png_user_chunk_malloc_max.
@@ -3886,7 +3886,7 @@
 Version 1.6.0beta07 [January 28, 2012]
   Eliminated Intel icc/icl compiler warnings. The Intel (GCC derived)
     compiler issues slightly different warnings from those issued by the
-    current vesions of GCC. This eliminates those warnings by
+    current versions of GCC. This eliminates those warnings by
     adding/removing casts and small code rewrites.
   Updated configure.ac from autoupdate: added --enable-werror option.
     Also some layout regularization and removal of introduced tab characters
@@ -3919,7 +3919,7 @@
     version checking to configure.ac
   Improved pngstest speed by not doing redundant tests and add const to
     the background parameter of png_image_finish_read. The --background
-    option is now done automagically only when required, so that commandline
+    option is now done automagically only when required, so that command-line
     option no longer exists.
   Cleaned up pngpriv.h to consistently declare all functions and data.
     Also eliminated PNG_CONST_DATA, which is apparently not needed but we
@@ -4052,7 +4052,7 @@
     (in fact this is harmless, but the PNG data produced may be sub-optimal).
 
 Version 1.6.0beta17 [March 10, 2012]
-  Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition. 
+  Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition.
   Reject all iCCP chunks after the first, even if the first one is invalid.
   Deflate/inflate was reworked to move common zlib calls into single
     functions [rw]util.c.  A new shared keyword check routine was also added
@@ -4962,7 +4962,7 @@
   Changed "if defined(__ARM_NEON__)" to
     "if (defined(__ARM_NEON__) || defined(__ARM_NEON))" (James Wu).
   Fixed clang no-warning builds: png_digit was defined but never used.
-    
+
 Version 1.6.13beta02 [July 21, 2014]
   Fixed an incorrect separator ("/" should be "\") in scripts/makefile.vcwin32
     (bug report from Wolfgang S. Kechel).  Bug was introduced in libpng-1.6.11.
@@ -5453,7 +5453,7 @@
 Version 1.6.21beta02 [December 14, 2015]
   Moved png_check_keyword() from pngwutil.c to pngset.c
   Removed LE/BE dependencies in pngvalid, to 'fix' the current problem
-    in the BigEndian tests by not testing it, making the BE code the same 
+    in the BigEndian tests by not testing it, making the BE code the same
     as the LE version.
   Fixes to pngvalid for various reduced build configurations (eliminate unused
     statics) and a fix for the case in rgb_to_gray when the digitize option
@@ -5517,7 +5517,7 @@
   Added a common-law trademark notice and export control information
     to the LICENSE file, png.h, and the man page.
   Restored "& 0xff" in png_save_uint_16() and png_save_uint_32() that
-    were accidentally removed from libpng-1.6.17. 
+    were accidentally removed from libpng-1.6.17.
   Changed PNG_INFO_cHNK and PNG_FREE_cHNK from 0xnnnn to 0xnnnnU in png.h
     (Robert C. Seacord).
   Removed dubious "#if INT_MAX" test from png.h that was added to
@@ -5927,7 +5927,7 @@
     (Bug report from the OSS-fuzz project).
 
 Version 1.6.32beta04 [August 2, 2017]
-  Replaced local eXIf_buf with info_ptr-eXIf_buf in png_handle_eXIf().
+  Replaced local eXIf_buf with info_ptr->eXIf_buf in png_handle_eXIf().
   Update libpng.3 and libpng-manual.txt about eXIf functions.
 
 Version 1.6.32beta05 [August 2, 2017]
@@ -5950,7 +5950,7 @@
   Require cmake-2.8.8 in CMakeLists.txt. Revised symlink creation,
     no longer using deprecated cmake LOCATION feature (Clifford Yapp).
   Fixed five-byte error in the calculation of IDAT maximum possible size.
-  
+
 Version 1.6.32beta10 [August 5, 2017]
   Moved chunk-length check into a png_check_chunk_length() private
     function (Suggested by Max Stepin).
@@ -6103,7 +6103,71 @@
   Added makefiles for AddressSanitizer-enabled builds.
   Cleaned up various makefiles.
 
-Version 1.6.38 [TODO]
+Version 1.6.38 [September 14, 2022]
+  Added configurations and scripts for continuous integration.
+  Fixed various errors in the handling of tRNS, hIST and eXIf.
+  Implemented many stability improvements across all platforms.
+  Updated the internal documentation.
+
+Version 1.6.39 [November 20, 2022]
+  Changed the error handler of oversized chunks (i.e. larger than
+    PNG_USER_CHUNK_MALLOC_MAX) from png_chunk_error to png_benign_error.
+  Fixed a buffer overflow error in contrib/tools/pngfix.
+  Fixed a memory leak (CVE-2019-6129) in contrib/tools/pngcp.
+  Disabled the ARM Neon optimizations by default in the CMake file,
+    following the default behavior of the configure script.
+  Allowed configure.ac to work with the trunk version of autoconf.
+  Removed the support for "install" targets from the legacy makefiles;
+    removed the obsolete makefile.cegcc.
+  Cleaned up the code and updated the internal documentation.
+
+Version 1.6.40 [June 21, 2023]
+  Fixed the eXIf chunk multiplicity checks.
+  Fixed a memory leak in pCAL processing.
+  Corrected the validity report about tRNS inside png_get_valid().
+  Fixed various build issues on *BSD, Mac and Windows.
+  Updated the configurations and the scripts for continuous integration.
+  Cleaned up the code, the build scripts, and the documentation.
+
+Version 1.6.41 [January 24, 2024]
+  Added SIMD-optimized code for the Loongarch LSX hardware.
+    (Contributed by GuXiWei, JinBo and ZhangLixia)
+  Fixed the run-time discovery of MIPS MSA hardware.
+    (Contributed by Sui Jingfeng)
+  Fixed an off-by-one error in the function png_do_check_palette_indexes(),
+    which failed to recognize errors that might have existed in the first
+    column of a broken palette-encoded image. This was a benign regression
+    accidentally introduced in libpng-1.6.33. No pixel was harmed.
+    (Contributed by Adam Richter; reviewed by John Bowler)
+  Fixed, improved and modernized the contrib/pngminus programs, i.e.,
+    png2pnm.c and pnm2png.c
+  Removed old and peculiar portability hacks that were meant to silence
+    warnings issued by gcc version 7.1 alone.
+    (Contributed by John Bowler)
+  Fixed and modernized the CMake file, and raised the minimum required
+    CMake version from 3.1 to 3.6.
+    (Contributed by Clinton Ingram, Timothy Lyanguzov, Tyler Kropp, et al.)
+  Allowed the configure script to disable the building of auxiliary tools
+    and tests, thus catching up with the CMake file.
+    (Contributed by Carlo Bramini)
+  Fixed a build issue on Mac.
+    (Contributed by Zixu Wang)
+  Moved the Autoconf macro files to scripts/autoconf.
+  Moved the CMake files (except for the main CMakeLists.txt) to
+    scripts/cmake and moved the list of their contributing authors to
+    scripts/cmake/AUTHORS.md
+  Updated the CI configurations and scripts.
+  Relicensed the CI scripts to the MIT License.
+  Improved the test coverage.
+    (Contributed by John Bowler)
+
+Version 1.6.42 [January 29, 2024]
+  Fixed the implementation of the macro function png_check_sig().
+    This was an API regression, introduced in libpng-1.6.41.
+    (Reported by Matthieu Darbois)
+  Fixed and updated the libpng manual.
+
+Version 1.6.43 [TODO]
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
 Subscription is required; visit
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 471949d..9cf62ba 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,94 +1,156 @@
-# CMakeLists.txt
 
-# Copyright (c) 2018-2019 Cosmin Truta
-# Copyright (c) 2007,2009-2018 Glenn Randers-Pehrson
-# Written by Christian Ehrlicher, 2007
-# Revised by Roger Lowman, 2009-2010
-# Revised by Clifford Yapp, 2011-2012,2017
-# Revised by Roger Leigh, 2016
-# Revised by Andreas Franek, 2016
-# Revised by Sam Serrels, 2017
-# Revised by Vadim Barkov, 2017
-# Revised by Vicky Pfau, 2018
-# Revised by Cameron Cawley, 2018
-# Revised by Cosmin Truta, 2018
-# Revised by Kyle Bentley, 2018
+# CMakeLists.txt - CMake lists for libpng
+#
+# Copyright (c) 2018-2024 Cosmin Truta.
+# Copyright (c) 2007-2018 Glenn Randers-Pehrson.
+# Originally written by Christian Ehrlicher, 2007.
+#
+# Use, modification and distribution are subject to
+# the same licensing terms and conditions as libpng.
+# Please see the copyright notice in png.h or visit
+# http://libpng.org/pub/png/src/libpng-LICENSE.txt
+#
+# For copyright and licensing purposes, please see
+# the accompanying file scripts/cmake/AUTHORS.md
+#
+# SPDX-License-Identifier: libpng-2.0
 
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-cmake_minimum_required(VERSION 3.1)
-cmake_policy(VERSION 3.1)
-
-project(libpng C ASM)
-enable_testing()
+cmake_minimum_required(VERSION 3.6)
 
 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 38)
-set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
-set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
+set(PNGLIB_REVISION 43)
+#set(PNGLIB_SUBREVISION 0)
+set(PNGLIB_SUBREVISION "git")
+set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_REVISION})
+set(PNGLIB_ABI_VERSION ${PNGLIB_MAJOR}${PNGLIB_MINOR})
+set(PNGLIB_SHARED_VERSION ${PNGLIB_ABI_VERSION}.${PNGLIB_REVISION}.${PNGLIB_SUBREVISION})
 
+project(libpng
+        VERSION ${PNGLIB_VERSION}
+        LANGUAGES C ASM)
+
+if(POLICY CMP0074)
+  # Allow find_package() to use the ZLIB_ROOT variable, if available.
+  cmake_policy(SET CMP0074 NEW)
+endif()
+
+include(CheckCSourceCompiles)
 include(GNUInstallDirs)
 
-# needed packages
+# Allow the users to specify an application-specific API prefix for libpng
+# vendoring purposes. A standard libpng build should have no such prefix.
+set(PNG_PREFIX ""
+    CACHE STRING "Prefix to prepend to the API function names")
 
-# Allow users to specify location of Zlib.
-# Useful if zlib is being built alongside this as a sub-project.
-option(PNG_BUILD_ZLIB "Custom zlib Location, else find_package is used" OFF)
+# Allow the users to override the postfix appended to debug library file names.
+# Previously, we used to set CMAKE_DEBUG_POSTFIX globally. That variable should
+# not be cached, however, because doing so would affect all projects processed
+# after libpng, in unexpected and undesirable ways.
+set(PNG_DEBUG_POSTFIX "d"
+    CACHE STRING "Postfix to append to library file names under the Debug configuration")
 
-if(NOT PNG_BUILD_ZLIB)
-  find_package(ZLIB REQUIRED)
-  include_directories(${ZLIB_INCLUDE_DIR})
+# Allow the users to import their own extra configuration settings.
+set(DFA_XTRA ""
+    CACHE FILEPATH "File containing extra configuration settings")
+
+# Allow the users to switch on/off various library build types.
+option(PNG_SHARED "Build libpng as a shared library" ON)
+option(PNG_STATIC "Build libpng as a static library" ON)
+if(APPLE)
+  option(PNG_FRAMEWORK "Build libpng as a framework bundle" ON)
 endif()
 
-if(UNIX AND NOT APPLE AND NOT BEOS AND NOT HAIKU)
-  find_library(M_LIBRARY m)
-else()
-  # libm is not needed and/or not available
-  set(M_LIBRARY "")
+# Allow the users to switch on/off the auxiliary build and test artifacts.
+# NOTE: These artifacts are NOT part of libpng proper, and are subject to change at any time.
+option(PNG_TESTS "Build the libpng tests" ON)
+option(PNG_TOOLS "Build the libpng tools" ON)
+
+# Maintain backwards compatibility with the deprecated option PNG_EXECUTABLES.
+option(PNG_EXECUTABLES "[Deprecated; please use PNG_TOOLS]" ON)
+if(NOT PNG_EXECUTABLES)
+  message(DEPRECATION "The option PNG_EXECUTABLES has been deprecated in favour of PNG_TOOLS")
+  if(PNG_TOOLS)
+    message(AUTHOR_WARNING
+            "Setting PNG_TOOLS to ${PNG_EXECUTABLES}, to stay compatible with PNG_EXECUTABLES")
+    set(PNG_TOOLS "${PNG_EXECUTABLES}")
+  endif()
 endif()
 
-# COMMAND LINE OPTIONS
-option(PNG_SHARED "Build shared lib" ON)
-option(PNG_STATIC "Build static lib" ON)
-option(PNG_TESTS  "Build libpng tests" ON)
-
-# Many more configuration options could be added here
-option(PNG_FRAMEWORK "Build OS X framework" OFF)
-option(PNG_DEBUG "Build with debug output" OFF)
+# Allow the users to configure various compilation options.
+option(PNG_DEBUG "Enable debug output" OFF)
 option(PNG_HARDWARE_OPTIMIZATIONS "Enable hardware optimizations" ON)
 
-set(PNG_PREFIX "" CACHE STRING "Prefix to add to the API function names")
-set(DFA_XTRA "" CACHE FILEPATH "File containing extra configuration settings")
+# Allow the users to specify a custom location of zlib.
+# This option is deprecated, and no longer needed with CMake 3.12 and newer.
+# Under the CMake policy CMP0074, if zlib is being built alongside libpng as a
+# subproject, its location can be passed on to CMake via the ZLIB_ROOT variable.
+option(PNG_BUILD_ZLIB "Custom zlib location, else find_package is used" OFF)
+if(NOT PNG_BUILD_ZLIB)
+  find_package(ZLIB REQUIRED)
+elseif(POLICY CMP0074)
+  # TODO: Remove the policy check if CMake version 3.12 or greater becomes the minimum required.
+  if("x${ZLIB_ROOT}" STREQUAL "x")
+    message(DEPRECATION
+            "The option PNG_BUILD_ZLIB has been deprecated; please use ZLIB_ROOT instead")
+  else()
+    message(SEND_ERROR
+            "The option PNG_BUILD_ZLIB=${PNG_BUILD_ZLIB} and "
+            "the variable ZLIB_ROOT=\"${ZLIB_ROOT}\" are mutually exclusive")
+  endif()
+endif()
+
+if(UNIX AND NOT APPLE AND NOT BEOS AND NOT HAIKU AND NOT EMSCRIPTEN)
+  find_library(M_LIBRARY m)
+  if(M_LIBRARY)
+    set(M_LIBRARY m)
+  else()
+    set(M_LIBRARY "")
+  endif()
+else()
+  # libm is not available or not needed.
+endif()
+
+# CMake currently sets CMAKE_SYSTEM_PROCESSOR to one of x86_64 or arm64 on macOS,
+# based upon the OS architecture, not the target architecture. As such, we need
+# to check CMAKE_OSX_ARCHITECTURES to identify which hardware-specific flags to
+# enable. Note that this will fail if you attempt to build a universal binary in
+# a single CMake invocation.
+if (APPLE AND CMAKE_OSX_ARCHITECTURES)
+  set(TARGET_ARCH ${CMAKE_OSX_ARCHITECTURES})
+else()
+  set(TARGET_ARCH ${CMAKE_SYSTEM_PROCESSOR})
+endif()
 
 if(PNG_HARDWARE_OPTIMIZATIONS)
 
-# set definitions and sources for arm
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^arm" OR
-  CMAKE_SYSTEM_PROCESSOR MATCHES "^aarch64")
-  set(PNG_ARM_NEON_POSSIBLE_VALUES check on off)
-  set(PNG_ARM_NEON "check" CACHE STRING "Enable ARM NEON optimizations:
-     check: (default) use internal checking code;
-     off: disable the optimizations;
-     on: turn on unconditionally.")
-  set_property(CACHE PNG_ARM_NEON PROPERTY STRINGS
-     ${PNG_ARM_NEON_POSSIBLE_VALUES})
+# Set definitions and sources for ARM.
+if(TARGET_ARCH MATCHES "^(ARM|arm|aarch)")
+  if(TARGET_ARCH MATCHES "^(ARM64|arm64|aarch64)")
+    set(PNG_ARM_NEON_POSSIBLE_VALUES on off)
+    set(PNG_ARM_NEON "on"
+        CACHE STRING "Enable ARM NEON optimizations: on|off; on is default")
+  else()
+    set(PNG_ARM_NEON_POSSIBLE_VALUES check on off)
+    set(PNG_ARM_NEON "off"
+        CACHE STRING "Enable ARM NEON optimizations: check|on|off; off is default")
+  endif()
+  set_property(CACHE PNG_ARM_NEON
+               PROPERTY STRINGS ${PNG_ARM_NEON_POSSIBLE_VALUES})
   list(FIND PNG_ARM_NEON_POSSIBLE_VALUES ${PNG_ARM_NEON} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_ARM_NEON must be one of [${PNG_ARM_NEON_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_ARM_NEON} STREQUAL "off")
+    message(FATAL_ERROR "PNG_ARM_NEON must be one of [${PNG_ARM_NEON_POSSIBLE_VALUES}]")
+  elseif(NOT PNG_ARM_NEON STREQUAL "off")
     set(libpng_arm_sources
-      arm/arm_init.c
-      arm/filter_neon.S
-      arm/filter_neon_intrinsics.c
-      arm/palette_neon_intrinsics.c)
-
-    if(${PNG_ARM_NEON} STREQUAL "on")
+        arm/arm_init.c
+        arm/filter_neon_intrinsics.c
+        arm/palette_neon_intrinsics.c)
+    if(NOT MSVC)
+      list(APPEND libpng_arm_sources arm/filter_neon.S)
+    endif()
+    if(PNG_ARM_NEON STREQUAL "on")
       add_definitions(-DPNG_ARM_NEON_OPT=2)
-    elseif(${PNG_ARM_NEON} STREQUAL "check")
+    elseif(PNG_ARM_NEON STREQUAL "check")
       add_definitions(-DPNG_ARM_NEON_CHECK_SUPPORTED)
     endif()
   else()
@@ -96,23 +158,21 @@
   endif()
 endif()
 
-# set definitions and sources for powerpc
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^powerpc*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^ppc64*")
+# Set definitions and sources for PowerPC.
+if(TARGET_ARCH MATCHES "^(powerpc|ppc64)")
   set(PNG_POWERPC_VSX_POSSIBLE_VALUES on off)
-  set(PNG_POWERPC_VSX "on" CACHE STRING "Enable POWERPC VSX optimizations:
-     off: disable the optimizations.")
-  set_property(CACHE PNG_POWERPC_VSX PROPERTY STRINGS
-     ${PNG_POWERPC_VSX_POSSIBLE_VALUES})
+  set(PNG_POWERPC_VSX "on"
+      CACHE STRING "Enable POWERPC VSX optimizations: on|off; on is default")
+  set_property(CACHE PNG_POWERPC_VSX
+               PROPERTY STRINGS ${PNG_POWERPC_VSX_POSSIBLE_VALUES})
   list(FIND PNG_POWERPC_VSX_POSSIBLE_VALUES ${PNG_POWERPC_VSX} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_POWERPC_VSX must be one of [${PNG_POWERPC_VSX_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_POWERPC_VSX} STREQUAL "off")
+    message(FATAL_ERROR "PNG_POWERPC_VSX must be one of [${PNG_POWERPC_VSX_POSSIBLE_VALUES}]")
+  elseif(NOT PNG_POWERPC_VSX STREQUAL "off")
     set(libpng_powerpc_sources
-      powerpc/powerpc_init.c
-      powerpc/filter_vsx_intrinsics.c)
-    if(${PNG_POWERPC_VSX} STREQUAL "on")
+        powerpc/powerpc_init.c
+        powerpc/filter_vsx_intrinsics.c)
+    if(PNG_POWERPC_VSX STREQUAL "on")
       add_definitions(-DPNG_POWERPC_VSX_OPT=2)
     endif()
   else()
@@ -120,23 +180,21 @@
   endif()
 endif()
 
-# set definitions and sources for intel
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^i?86" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^x86_64*")
+# Set definitions and sources for Intel.
+if(TARGET_ARCH MATCHES "^(i[3-6]86|x86|AMD64)")
   set(PNG_INTEL_SSE_POSSIBLE_VALUES on off)
-  set(PNG_INTEL_SSE "on" CACHE STRING "Enable INTEL_SSE optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_INTEL_SSE PROPERTY STRINGS
-     ${PNG_INTEL_SSE_POSSIBLE_VALUES})
+  set(PNG_INTEL_SSE "on"
+      CACHE STRING "Enable INTEL_SSE optimizations: on|off; on is default")
+  set_property(CACHE PNG_INTEL_SSE
+               PROPERTY STRINGS ${PNG_INTEL_SSE_POSSIBLE_VALUES})
   list(FIND PNG_INTEL_SSE_POSSIBLE_VALUES ${PNG_INTEL_SSE} index)
   if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_INTEL_SSE must be one of [${PNG_INTEL_SSE_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_INTEL_SSE} STREQUAL "off")
+    message(FATAL_ERROR "PNG_INTEL_SSE must be one of [${PNG_INTEL_SSE_POSSIBLE_VALUES}]")
+  elseif(NOT PNG_INTEL_SSE STREQUAL "off")
     set(libpng_intel_sources
-      intel/intel_init.c
-      intel/filter_sse2_intrinsics.c)
-    if(${PNG_INTEL_SSE} STREQUAL "on")
+        intel/intel_init.c
+        intel/filter_sse2_intrinsics.c)
+    if(PNG_INTEL_SSE STREQUAL "on")
       add_definitions(-DPNG_INTEL_SSE_OPT=1)
     endif()
   else()
@@ -144,142 +202,173 @@
   endif()
 endif()
 
-# set definitions and sources for MIPS
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "mipsel*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "mips64el*")
+# Set definitions and sources for MIPS.
+if(TARGET_ARCH MATCHES "^(mipsel|mips64el)")
   set(PNG_MIPS_MSA_POSSIBLE_VALUES on off)
-  set(PNG_MIPS_MSA "on" CACHE STRING "Enable MIPS_MSA optimizations:
-     off: disable the optimizations")
-  set_property(CACHE PNG_MIPS_MSA PROPERTY STRINGS
-     ${PNG_MIPS_MSA_POSSIBLE_VALUES})
-  list(FIND PNG_MIPS_MSA_POSSIBLE_VALUES ${PNG_MIPS_MSA} index)
-  if(index EQUAL -1)
-    message(FATAL_ERROR
-            "PNG_MIPS_MSA must be one of [${PNG_MIPS_MSA_POSSIBLE_VALUES}]")
-  elseif(NOT ${PNG_MIPS_MSA} STREQUAL "off")
+  set(PNG_MIPS_MSA "on"
+      CACHE STRING "Enable MIPS_MSA optimizations: on|off; on is default")
+  set_property(CACHE PNG_MIPS_MSA
+               PROPERTY STRINGS ${PNG_MIPS_MSA_POSSIBLE_VALUES})
+  list(FIND PNG_MIPS_MSA_POSSIBLE_VALUES ${PNG_MIPS_MSA} index_msa)
+  if(index_msa EQUAL -1)
+    message(FATAL_ERROR "PNG_MIPS_MSA must be one of [${PNG_MIPS_MSA_POSSIBLE_VALUES}]")
+  endif()
+
+  set(PNG_MIPS_MMI_POSSIBLE_VALUES on off)
+  set(PNG_MIPS_MMI "on"
+      CACHE STRING "Enable MIPS_MMI optimizations: on|off; on is default")
+  set_property(CACHE PNG_MIPS_MMI
+               PROPERTY STRINGS ${PNG_MIPS_MMI_POSSIBLE_VALUES})
+  list(FIND PNG_MIPS_MMI_POSSIBLE_VALUES ${PNG_MIPS_MMI} index_mmi)
+  if(index_mmi EQUAL -1)
+    message(FATAL_ERROR "PNG_MIPS_MMI must be one of [${PNG_MIPS_MMI_POSSIBLE_VALUES}]")
+  endif()
+
+  if(PNG_MIPS_MSA STREQUAL "on" AND PNG_MIPS_MMI STREQUAL "on")
     set(libpng_mips_sources
-      mips/mips_init.c
-      mips/filter_msa_intrinsics.c)
-    if(${PNG_MIPS_MSA} STREQUAL "on")
-      add_definitions(-DPNG_MIPS_MSA_OPT=2)
+        mips/mips_init.c
+        mips/filter_msa_intrinsics.c
+        mips/filter_mmi_inline_assembly.c)
+    add_definitions(-DPNG_MIPS_MSA_OPT=2)
+    add_definitions(-DPNG_MIPS_MMI_OPT=1)
+  elseif(PNG_MIPS_MSA STREQUAL "on")
+    set(libpng_mips_sources
+        mips/mips_init.c
+        mips/filter_msa_intrinsics.c)
+    add_definitions(-DPNG_MIPS_MSA_OPT=2)
+    add_definitions(-DPNG_MIPS_MMI_OPT=0)
+  elseif(PNG_MIPS_MMI STREQUAL "on")
+    set(libpng_mips_sources
+        mips/mips_init.c
+        mips/filter_mmi_inline_assembly.c)
+    add_definitions(-DPNG_MIPS_MSA_OPT=0)
+    add_definitions(-DPNG_MIPS_MMI_OPT=1)
+    else()
+    add_definitions(-DPNG_MIPS_MSA_OPT=0)
+    add_definitions(-DPNG_MIPS_MMI_OPT=0)
+    endif()
+endif()
+
+# Set definitions and sources for LoongArch.
+if(TARGET_ARCH MATCHES "^(loongarch)")
+  include(CheckCCompilerFlag)
+  set(PNG_LOONGARCH_LSX_POSSIBLE_VALUES on off)
+  set(PNG_LOONGARCH_LSX "on"
+      CACHE STRING "Enable LOONGARCH_LSX optimizations: on|off; on is default")
+  set_property(CACHE PNG_LOONGARCH_LSX
+               PROPERTY STRINGS ${PNG_LOONGARCH_LSX_POSSIBLE_VALUES})
+  list(FIND PNG_LOONGARCH_LSX_POSSIBLE_VALUES ${PNG_LOONGARCH_LSX} index)
+  if(index EQUAL -1)
+    message(FATAL_ERROR "PNG_LOONGARCH_LSX must be one of [${PNG_LOONGARCH_LSX_POSSIBLE_VALUES}]")
+  elseif(NOT PNG_LOONGARCH_LSX STREQUAL "off")
+    CHECK_C_COMPILER_FLAG("-mlsx" COMPILER_SUPPORTS_LSX)
+    if(COMPILER_SUPPORTS_LSX)
+      set(libpng_loongarch_sources
+          loongarch/loongarch_lsx_init.c
+	  loongarch/filter_lsx_intrinsics.c)
+      set_source_files_properties(${libpng_loongarch_sources}
+                                  PROPERTIES
+                                  COMPILE_FLAGS "-mlsx")
+      add_definitions(-DPNG_LOONGARCH_LSX_OPT=1)
+    else()
+      message(FATAL_ERROR "Compiler does not support -mlsx option")
     endif()
   else()
-    add_definitions(-DPNG_MIPS_MSA_OPT=0)
+    add_definitions(-DPNG_LOONGARCH_LSX_OPT=0)
   endif()
 endif()
 
 else(PNG_HARDWARE_OPTIMIZATIONS)
 
-# set definitions and sources for arm
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^arm" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^aarch64")
+# Set definitions and sources for ARM.
+if(TARGET_ARCH MATCHES "^(ARM|arm|aarch)")
   add_definitions(-DPNG_ARM_NEON_OPT=0)
 endif()
 
-# set definitions and sources for powerpc
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^powerpc*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^ppc64*")
+# Set definitions and sources for PowerPC.
+if(TARGET_ARCH MATCHES "^(powerpc|ppc64)")
   add_definitions(-DPNG_POWERPC_VSX_OPT=0)
 endif()
 
-# set definitions and sources for intel
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "^i?86" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "^x86_64*")
+# Set definitions and sources for Intel.
+if(TARGET_ARCH MATCHES "^(i[3-6]86|x86|AMD64)")
   add_definitions(-DPNG_INTEL_SSE_OPT=0)
 endif()
 
-# set definitions and sources for MIPS
-if(CMAKE_SYSTEM_PROCESSOR MATCHES "mipsel*" OR
-   CMAKE_SYSTEM_PROCESSOR MATCHES "mips64el*")
+# Set definitions and sources for MIPS.
+if(TARGET_ARCH MATCHES "^(mipsel|mips64el)")
   add_definitions(-DPNG_MIPS_MSA_OPT=0)
 endif()
 
+# Set definitions and sources for LoongArch.
+if(TARGET_ARCH MATCHES "^(loongarch)")
+	add_definitions(-DPNG_LOONGARCH_LSX_OPT=0)
+endif()
+
 endif(PNG_HARDWARE_OPTIMIZATIONS)
 
-# SET LIBNAME
-set(PNG_LIB_NAME png${PNGLIB_MAJOR}${PNGLIB_MINOR})
-
-# to distinguish between debug and release lib
-set(CMAKE_DEBUG_POSTFIX "d")
-
-include(CheckCSourceCompiles)
 option(ld-version-script "Enable linker version script" ON)
-if(ld-version-script AND NOT APPLE)
+if(ld-version-script AND NOT ANDROID AND NOT APPLE)
   # Check if LD supports linker scripts.
-  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "VERS_1 {
-        global: sym;
-        local: *;
-};
-
-VERS_2 {
-        global: sym2;
-                main;
-} VERS_1;
+  file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map" "
+VERS_1 { global: sym1; local: *; };
+VERS_2 { global: sym2; main; } VERS_1;
 ")
-  set(CMAKE_REQUIRED_FLAGS_SAVE ${CMAKE_REQUIRED_FLAGS})
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS} "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/conftest.map'")
-  check_c_source_compiles("void sym(void) {}
+  set(_SAVED_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
+  if(NOT CMAKE_HOST_SOLARIS)
+    # Avoid using CMAKE_SHARED_LIBRARY_C_FLAGS in version script checks on
+    # Solaris, because of an incompatibility with the Solaris link editor.
+    list(APPEND CMAKE_REQUIRED_FLAGS ${CMAKE_SHARED_LIBRARY_C_FLAGS})
+  endif()
+  list(APPEND CMAKE_REQUIRED_FLAGS "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/conftest.map'")
+  check_c_source_compiles("
+void sym1(void) {}
 void sym2(void) {}
-int main(void) {return 0;}
+int main(void) { return 0; }
 " HAVE_LD_VERSION_SCRIPT)
   if(NOT HAVE_LD_VERSION_SCRIPT)
-    set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE} "-Wl,-M -Wl,${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
-  check_c_source_compiles("void sym(void) {}
+    set(CMAKE_REQUIRED_FLAGS ${_SAVED_CMAKE_REQUIRED_FLAGS})
+    if(NOT CMAKE_HOST_SOLARIS)
+      # Again, avoid using CMAKE_SHARED_LIBRARY_C_FLAGS in version script
+      # checks on Solaris.
+      list(APPEND CMAKE_REQUIRED_FLAGS ${CMAKE_SHARED_LIBRARY_C_FLAGS})
+    endif()
+    list(APPEND CMAKE_REQUIRED_FLAGS "-Wl,-M -Wl,${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
+    check_c_source_compiles("
+void sym1(void) {}
 void sym2(void) {}
-int main(void) {return 0;}
+int main(void) { return 0; }
 " HAVE_SOLARIS_LD_VERSION_SCRIPT)
   endif()
-  set(CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS_SAVE})
+  set(CMAKE_REQUIRED_FLAGS ${_SAVED_CMAKE_REQUIRED_FLAGS})
   file(REMOVE "${CMAKE_CURRENT_BINARY_DIR}/conftest.map")
 endif()
 
-# Find symbol prefix.  Likely obsolete and unnecessary with recent
-# toolchains (it's not done in many other projects).
-function(symbol_prefix)
-  set(SYMBOL_PREFIX)
-
-  execute_process(COMMAND "${CMAKE_C_COMPILER}" "-E" "-"
-                  INPUT_FILE /dev/null
-                  OUTPUT_VARIABLE OUT
-                  RESULT_VARIABLE STATUS)
-
-  if(CPP_FAIL)
-    message(WARNING "Failed to run the C preprocessor")
-  endif()
-
-  string(REPLACE "\n" ";" OUT "${OUT}")
-  foreach(line ${OUT})
-    string(REGEX MATCH "^PREFIX=" found_match "${line}")
-    if(found_match)
-      string(REGEX REPLACE "^PREFIX=(.*\)" "\\1" prefix "${line}")
-      string(REGEX MATCH "__USER_LABEL_PREFIX__" found_match "${prefix}")
-      if(found_match)
-        string(REGEX REPLACE "(.*)__USER_LABEL_PREFIX__(.*)" "\\1\\2" prefix "${prefix}")
-      endif()
-      set(SYMBOL_PREFIX "${prefix}")
-    endif()
-  endforeach()
-
-  message(STATUS "Symbol prefix: ${SYMBOL_PREFIX}")
-  set(SYMBOL_PREFIX "${SYMBOL_PREFIX}" PARENT_SCOPE)
-endfunction()
-
-if(UNIX)
-  symbol_prefix()
-endif()
-
 find_program(AWK NAMES gawk awk)
 
 include_directories(${CMAKE_CURRENT_BINARY_DIR})
 
-if(NOT AWK OR ANDROID)
+if(NOT AWK OR ANDROID OR IOS)
   # No awk available to generate sources; use pre-built pnglibconf.h
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt
                  ${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h)
-  add_custom_target(genfiles) # Dummy
+  add_custom_target(png_genfiles)
 else()
-  include(CMakeParseArguments)
-  # Generate .chk from .out with awk
+  # Copy the awk scripts, converting their line endings to Unix (LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/checksym.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+  configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/dfn.awk
+                 ${CMAKE_CURRENT_BINARY_DIR}/scripts/dfn.awk
+                 @ONLY
+                 NEWLINE_STYLE LF)
+
+  # Generate .chk from .out with awk:
   # generate_chk(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
   function(generate_chk)
     set(options)
@@ -297,7 +386,7 @@
                        COMMAND "${CMAKE_COMMAND}"
                                "-DINPUT=${_GC_INPUT}"
                                "-DOUTPUT=${_GC_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake"
+                               -P "${CMAKE_CURRENT_BINARY_DIR}/genchk.cmake"
                        DEPENDS "${_GC_INPUT}" ${_GC_DEPENDS}
                        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
   endfunction()
@@ -320,7 +409,7 @@
                        COMMAND "${CMAKE_COMMAND}"
                                "-DINPUT=${_GO_INPUT}"
                                "-DOUTPUT=${_GO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake"
+                               -P "${CMAKE_CURRENT_BINARY_DIR}/genout.cmake"
                        DEPENDS "${_GO_INPUT}" ${_GO_DEPENDS}
                        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
   endfunction()
@@ -339,31 +428,48 @@
     add_custom_command(OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/${_GSO_OUTPUT}"
                        COMMAND "${CMAKE_COMMAND}"
                                "-DOUTPUT=${_GSO_OUTPUT}"
-                               -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
+                               -P "${CMAKE_CURRENT_BINARY_DIR}/gensrc.cmake"
                        DEPENDS ${_GSO_DEPENDS}
                        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
   endfunction()
 
   # Copy file
-  function(generate_copy source destination)
-    add_custom_command(OUTPUT "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E remove "${destination}"
-                       COMMAND "${CMAKE_COMMAND}" -E copy "${source}"
-                                                          "${destination}"
-                       DEPENDS "${source}")
+  # generate_copy(INPUT inputfile OUTPUT outputfile [DEPENDS dep1 [dep2...]])
+  function(generate_copy)
+    set(options)
+    set(oneValueArgs INPUT OUTPUT)
+    set(multiValueArgs DEPENDS)
+    cmake_parse_arguments(_GCO "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    if(NOT _GCO_INPUT)
+      message(FATAL_ERROR "generate_copy: Missing INPUT argument")
+    endif()
+    if(NOT _GCO_OUTPUT)
+      message(FATAL_ERROR "generate_copy: Missing OUTPUT argument")
+    endif()
+
+    add_custom_command(OUTPUT "${_GCO_OUTPUT}"
+                       COMMAND "${CMAKE_COMMAND}"
+                               -E remove "${_GCO_OUTPUT}"
+                       COMMAND "${CMAKE_COMMAND}"
+                               -E copy "${_GCO_INPUT}" "${_GCO_OUTPUT}"
+                       DEPENDS "${source}" ${_GCO_DEPENDS})
   endfunction()
 
   # Generate scripts/pnglibconf.h
   generate_source(OUTPUT "scripts/pnglibconf.c"
                   DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
+                          "${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk"
                           "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
+  add_custom_target(png_scripts_pnglibconf_c
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c")
 
   # Generate pnglibconf.c
   generate_source(OUTPUT "pnglibconf.c"
                   DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.dfa"
-                          "${CMAKE_CURRENT_SOURCE_DIR}/scripts/options.awk"
+                          "${CMAKE_CURRENT_BINARY_DIR}/scripts/options.awk"
                           "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h")
+  add_custom_target(pnglibconf_c
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c")
 
   if(PNG_PREFIX)
     set(PNGLIBCONF_H_EXTRA_DEPENDS
@@ -374,146 +480,167 @@
   endif()
 
   generate_out(INPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
+               OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
+               DEPENDS pnglibconf_c)
+  add_custom_target(pnglibconf_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
 
   # Generate pnglibconf.h
   generate_source(OUTPUT "pnglibconf.h"
-                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
+                  DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out
                           ${PNGLIBCONF_H_EXTRA_DEPENDS})
+  add_custom_target(pnglibconf_h
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/intprefix.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(png_scripts_intprefix_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/prefix.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out")
+                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out)
+  add_custom_target(png_scripts_prefix_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out")
 
   # Generate pngprefix.h
   generate_source(OUTPUT "pngprefix.h"
                   DEPENDS ${PNGPREFIX_H_EXTRA_DEPENDS})
+  add_custom_target(pngprefix_h
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/sym.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+               DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(png_scripts_sym_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/pnglibconf.h.prebuilt")
+  add_custom_target(png_scripts_symbols_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out")
 
   generate_out(INPUT "${CMAKE_CURRENT_SOURCE_DIR}/scripts/vers.c"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
                DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/png.h"
                        "${CMAKE_CURRENT_SOURCE_DIR}/pngconf.h"
-                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h")
+                       "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h)
+  add_custom_target(png_scripts_vers_out
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
 
   generate_chk(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-               DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/scripts/checksym.awk"
+               DEPENDS png_scripts_symbols_out
+                       "${CMAKE_CURRENT_BINARY_DIR}/scripts/checksym.awk"
                        "${CMAKE_CURRENT_SOURCE_DIR}/scripts/symbols.def")
 
-  add_custom_target(symbol-check DEPENDS
-                    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
+  add_custom_target(png_scripts_symbols_chk
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk")
 
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
-  generate_copy("${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
-                "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
+  generate_copy(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
+                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
+                DEPENDS png_scripts_sym_out)
+  generate_copy(INPUT "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out"
+                OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
+                DEPENDS png_scripts_vers_out)
 
-  add_custom_target(genvers DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
-  add_custom_target(gensym DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
+  add_custom_target(png_genvers
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers")
+  add_custom_target(png_gensym
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym")
 
-  add_custom_target("genprebuilt"
+  add_custom_target(png_genprebuilt
                     COMMAND "${CMAKE_COMMAND}"
                             "-DOUTPUT=scripts/pnglibconf.h.prebuilt"
-                            -P "${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake"
+                            -P "${CMAKE_CURRENT_BINARY_DIR}/gensrc.cmake"
                     WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
 
-  # A single target handles generation of all generated files.  If
-  # they are depended upon separately by multiple targets, this
-  # confuses parallel make (it would require a separate top-level
-  # target for each file to track the dependencies properly).
-  add_custom_target(genfiles DEPENDS
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym"
-    "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out"
-    "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out")
-endif(NOT AWK OR ANDROID)
+  # A single target handles generation of all generated files.
+  add_custom_target(png_genfiles
+                    DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/libpng.sym" png_gensym
+                            "${CMAKE_CURRENT_BINARY_DIR}/libpng.vers" png_genvers
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.c" pnglibconf_c
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h" pnglibconf_h
+                            "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.out" pnglibconf_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h" pngprefix_h
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/intprefix.out" png_scripts_intprefix_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/pnglibconf.c" png_scripts_pnglibconf_c
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/prefix.out" png_scripts_prefix_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/sym.out" png_scripts_sym_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.chk" png_scripts_symbols_chk
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/symbols.out" png_scripts_symbols_out
+                            "${CMAKE_CURRENT_BINARY_DIR}/scripts/vers.out" png_scripts_vers_out)
+endif(NOT AWK OR ANDROID OR IOS)
 
-# OUR SOURCES
+# List the source code files.
 set(libpng_public_hdrs
-  png.h
-  pngconf.h
-  "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
+    png.h
+    pngconf.h
+    "${CMAKE_CURRENT_BINARY_DIR}/pnglibconf.h"
 )
 set(libpng_private_hdrs
-  pngpriv.h
-  pngdebug.h
-  pnginfo.h
-  pngstruct.h
+    pngpriv.h
+    pngdebug.h
+    pnginfo.h
+    pngstruct.h
 )
-if(AWK AND NOT ANDROID)
+if(AWK AND NOT ANDROID AND NOT IOS)
   list(APPEND libpng_private_hdrs "${CMAKE_CURRENT_BINARY_DIR}/pngprefix.h")
 endif()
 set(libpng_sources
-  ${libpng_public_hdrs}
-  ${libpng_private_hdrs}
-  png.c
-  pngerror.c
-  pngget.c
-  pngmem.c
-  pngpread.c
-  pngread.c
-  pngrio.c
-  pngrtran.c
-  pngrutil.c
-  pngset.c
-  pngtrans.c
-  pngwio.c
-  pngwrite.c
-  pngwtran.c
-  pngwutil.c
-  ${libpng_arm_sources}
-  ${libpng_intel_sources}
-  ${libpng_mips_sources}
-  ${libpng_powerpc_sources}
+    ${libpng_public_hdrs}
+    ${libpng_private_hdrs}
+    png.c
+    pngerror.c
+    pngget.c
+    pngmem.c
+    pngpread.c
+    pngread.c
+    pngrio.c
+    pngrtran.c
+    pngrutil.c
+    pngset.c
+    pngtrans.c
+    pngwio.c
+    pngwrite.c
+    pngwtran.c
+    pngwutil.c
+    ${libpng_arm_sources}
+    ${libpng_intel_sources}
+    ${libpng_mips_sources}
+    ${libpng_powerpc_sources}
+    ${libpng_loongarch_sources}
 )
 set(pngtest_sources
-  pngtest.c
+    pngtest.c
 )
 set(pngvalid_sources
-  contrib/libtests/pngvalid.c
+    contrib/libtests/pngvalid.c
 )
 set(pngstest_sources
-  contrib/libtests/pngstest.c
+    contrib/libtests/pngstest.c
 )
 set(pngunknown_sources
-  contrib/libtests/pngunknown.c
+    contrib/libtests/pngunknown.c
 )
 set(pngimage_sources
-  contrib/libtests/pngimage.c
+    contrib/libtests/pngimage.c
 )
 set(pngfix_sources
-  contrib/tools/pngfix.c
+    contrib/tools/pngfix.c
 )
 set(png_fix_itxt_sources
-  contrib/tools/png-fix-itxt.c
+    contrib/tools/png-fix-itxt.c
 )
 
-if(MSVC)
+if(MSVC OR (WIN32 AND (CMAKE_C_COMPILER_ID MATCHES "Clang")))
+  add_definitions(-D_CRT_NONSTDC_NO_DEPRECATE)
   add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
 endif()
 
@@ -521,113 +648,135 @@
   add_definitions(-DPNG_DEBUG)
 endif()
 
-# NOW BUILD OUR TARGET
-include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${ZLIB_INCLUDE_DIR})
+# Now build our targets.
 
-unset(PNG_LIB_TARGETS)
+# Initialize the list of libpng library targets.
+set(PNG_LIBRARY_TARGETS "")
+
+# Initialize the libpng library file names.
+if(UNIX
+   OR (WIN32 AND NOT CMAKE_SHARED_LIBRARY_PREFIX STREQUAL "")
+   OR (WIN32 AND NOT CMAKE_STATIC_LIBRARY_PREFIX STREQUAL ""))
+  # We are on a Unix or Unix-like toolchain like the GNU toolchain on Windows.
+  # Library file names are expected to have an implicit prefix such as "lib".
+  # Let CMake prepend and append its usual prefixes and suffixes by default.
+  set(PNG_SHARED_OUTPUT_NAME "png${PNGLIB_ABI_VERSION}")
+  set(PNG_STATIC_OUTPUT_NAME "png${PNGLIB_ABI_VERSION}")
+else()
+  # We are, most likely, on a Windows toolchain like MSVC, Clang on Windows,
+  # Borland/Embarcadero, etc. We need to specify the "libpng" name explicitly.
+  # We also need to use a custom suffix, in order to distinguish between the
+  # shared import library name and the static library name.
+  set(PNG_SHARED_OUTPUT_NAME "libpng${PNGLIB_ABI_VERSION}")
+  set(PNG_STATIC_OUTPUT_NAME "libpng${PNGLIB_ABI_VERSION}_static")
+endif()
 
 if(PNG_SHARED)
-  add_library(png SHARED ${libpng_sources})
-  set(PNG_LIB_TARGETS png)
-  set_target_properties(png PROPERTIES OUTPUT_NAME ${PNG_LIB_NAME})
-  add_dependencies(png genfiles)
-  if(MSVC)
-    # msvc does not append 'lib' - do it here to have consistent name
-    set_target_properties(png PROPERTIES PREFIX "lib")
-    set_target_properties(png PROPERTIES IMPORT_PREFIX "lib")
-  endif()
-  target_link_libraries(png ${ZLIB_LIBRARY} ${M_LIBRARY})
-
+  add_library(png_shared SHARED ${libpng_sources})
+  add_dependencies(png_shared png_genfiles)
+  list(APPEND PNG_LIBRARY_TARGETS png_shared)
+  set_target_properties(png_shared PROPERTIES
+                        OUTPUT_NAME "${PNG_SHARED_OUTPUT_NAME}"
+                        DEBUG_POSTFIX "${PNG_DEBUG_POSTFIX}"
+                        VERSION "${PNGLIB_SHARED_VERSION}"
+                        SOVERSION "${PNGLIB_ABI_VERSION}")
   if(UNIX AND AWK)
     if(HAVE_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
+      set_target_properties(png_shared PROPERTIES
+                            LINK_FLAGS "-Wl,--version-script='${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
     elseif(HAVE_SOLARIS_LD_VERSION_SCRIPT)
-      set_target_properties(png PROPERTIES LINK_FLAGS
-        "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
+      set_target_properties(png_shared PROPERTIES
+                            LINK_FLAGS "-Wl,-M -Wl,'${CMAKE_CURRENT_BINARY_DIR}/libpng.vers'")
     endif()
   endif()
+  if(APPLE)
+    # Avoid CMake's implicit compile definition "png_shared_EXPORTS".
+    set_target_properties(png_shared PROPERTIES DEFINE_SYMBOL "")
+  elseif(WIN32)
+    # Use the explicit compile definition "PNG_BUILD_DLL" for Windows DLLs.
+    set_target_properties(png_shared PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
+  endif()
+  target_include_directories(png_shared
+                             PUBLIC
+                               $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/libpng${PNGLIB_ABI_VERSION}>
+                               $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+                             PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+  target_link_libraries(png_shared PUBLIC ZLIB::ZLIB ${M_LIBRARY})
 endif()
 
 if(PNG_STATIC)
-  # does not work without changing name
-  set(PNG_LIB_NAME_STATIC png_static)
   add_library(png_static STATIC ${libpng_sources})
-  add_dependencies(png_static genfiles)
-  # MSVC doesn't use a different file extension for shared vs. static
-  # libs.  We are able to change OUTPUT_NAME to remove the _static
-  # for all other platforms.
-  if(NOT MSVC)
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}"
-      CLEAN_DIRECT_OUTPUT 1)
-  else()
-    set_target_properties(png_static PROPERTIES
-      OUTPUT_NAME "${PNG_LIB_NAME}_static"
-      CLEAN_DIRECT_OUTPUT 1)
-  endif()
-  list(APPEND PNG_LIB_TARGETS png_static)
-  if(MSVC)
-    # msvc does not append 'lib' - do it here to have consistent name
-    set_target_properties(png_static PROPERTIES PREFIX "lib")
-  endif()
-  target_link_libraries(png_static ${ZLIB_LIBRARY} ${M_LIBRARY})
+  add_dependencies(png_static png_genfiles)
+  list(APPEND PNG_LIBRARY_TARGETS png_static)
+  set_target_properties(png_static PROPERTIES
+                        OUTPUT_NAME "${PNG_STATIC_OUTPUT_NAME}"
+                        DEBUG_POSTFIX "${PNG_DEBUG_POSTFIX}")
+  target_include_directories(png_static
+                             PUBLIC
+                               $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/libpng${PNGLIB_ABI_VERSION}>
+                               $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+                             PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+  target_link_libraries(png_static PUBLIC ZLIB::ZLIB ${M_LIBRARY})
 endif()
 
-if(PNG_FRAMEWORK)
-  set(PNG_LIB_NAME_FRAMEWORK png_framework)
+if(PNG_FRAMEWORK AND APPLE)
   add_library(png_framework SHARED ${libpng_sources})
-  add_dependencies(png_framework genfiles)
-  list(APPEND PNG_LIB_TARGETS png_framework)
+  add_dependencies(png_framework png_genfiles)
+  list(APPEND PNG_LIBRARY_TARGETS png_framework)
   set_target_properties(png_framework PROPERTIES
-    FRAMEWORK TRUE
-    FRAMEWORK_VERSION ${PNGLIB_VERSION}
-    MACOSX_FRAMEWORK_SHORT_VERSION_STRING ${PNGLIB_MAJOR}.${PNGLIB_MINOR}
-    MACOSX_FRAMEWORK_BUNDLE_VERSION ${PNGLIB_VERSION}
-    MACOSX_FRAMEWORK_IDENTIFIER org.libpng.libpng
-    XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
-    PUBLIC_HEADER "${libpng_public_hdrs}"
-    OUTPUT_NAME png)
-  target_link_libraries(png_framework ${ZLIB_LIBRARY} ${M_LIBRARY})
+                        FRAMEWORK TRUE
+                        FRAMEWORK_VERSION "${PNGLIB_VERSION}"
+                        MACOSX_FRAMEWORK_SHORT_VERSION_STRING "${PNGLIB_MAJOR}.${PNGLIB_MINOR}"
+                        MACOSX_FRAMEWORK_BUNDLE_VERSION "${PNGLIB_VERSION}"
+                        MACOSX_FRAMEWORK_IDENTIFIER "org.libpng.libpng"
+                        XCODE_ATTRIBUTE_INSTALL_PATH "@rpath"
+                        PUBLIC_HEADER "${libpng_public_hdrs}"
+                        OUTPUT_NAME "png"
+                        DEBUG_POSTFIX "${PNG_DEBUG_POSTFIX}")
+  # Avoid CMake's implicit compile definition "-Dpng_framework_EXPORTS".
+  set_target_properties(png_framework PROPERTIES DEFINE_SYMBOL "")
+  target_include_directories(png_framework
+                             PUBLIC
+                               $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/libpng${PNGLIB_ABI_VERSION}>
+                               $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+                             PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+  target_link_libraries(png_framework PUBLIC ZLIB::ZLIB ${M_LIBRARY})
 endif()
 
-if(NOT PNG_LIB_TARGETS)
-  message(SEND_ERROR
-    "No library variant selected to build. "
-    "Please enable at least one of the following options: "
-    "PNG_STATIC, PNG_SHARED, PNG_FRAMEWORK")
+if(NOT PNG_LIBRARY_TARGETS)
+  message(SEND_ERROR "No library variant selected to build. "
+                     "Please enable at least one of the following options: "
+                     "PNG_SHARED, PNG_STATIC, PNG_FRAMEWORK")
 endif()
 
-if(PNG_SHARED AND WIN32)
-  set_target_properties(png PROPERTIES DEFINE_SYMBOL PNG_BUILD_DLL)
-endif()
-
-function(png_add_test)
-  set(options)
-  set(oneValueArgs NAME COMMAND)
-  set(multiValueArgs OPTIONS FILES)
-  cmake_parse_arguments(_PAT "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
-
-  if(NOT _PAT_NAME)
-    message(FATAL_ERROR "png_add_test: Missing NAME argument")
-  endif()
-  if(NOT _PAT_COMMAND)
-    message(FATAL_ERROR "png_add_test: Missing COMMAND argument")
-  endif()
-
-  set(TEST_OPTIONS "${_PAT_OPTIONS}")
-  set(TEST_FILES "${_PAT_FILES}")
-
-  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/test.cmake.in"
-                 "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake" @ONLY)
-  add_test(NAME "${_PAT_NAME}"
-           COMMAND "${CMAKE_COMMAND}"
-           "-DLIBPNG=$<TARGET_FILE:png>"
-           "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
-           -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
-endfunction()
-
 if(PNG_TESTS AND PNG_SHARED)
+  enable_testing()
+
+  function(png_add_test)
+    set(options)
+    set(oneValueArgs NAME COMMAND)
+    set(multiValueArgs OPTIONS FILES)
+    cmake_parse_arguments(_PAT "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+    if(NOT _PAT_NAME)
+      message(FATAL_ERROR "png_add_test: Missing NAME argument")
+    endif()
+    if(NOT _PAT_COMMAND)
+      message(FATAL_ERROR "png_add_test: Missing COMMAND argument")
+    endif()
+
+    set(TEST_OPTIONS "${_PAT_OPTIONS}")
+    set(TEST_FILES "${_PAT_FILES}")
+
+    configure_file("${CMAKE_CURRENT_SOURCE_DIR}/scripts/cmake/test.cmake.in"
+                   "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake"
+                   @ONLY)
+    add_test(NAME "${_PAT_NAME}"
+             COMMAND "${CMAKE_COMMAND}"
+                     "-DLIBPNG=$<TARGET_FILE:png_shared>"
+                     "-DTEST_COMMAND=$<TARGET_FILE:${_PAT_COMMAND}>"
+                     -P "${CMAKE_CURRENT_BINARY_DIR}/tests/${_PAT_NAME}.cmake")
+  endfunction()
+
   # Find test PNG files by globbing, but sort lists to ensure
   # consistency between different filesystems.
   file(GLOB PNGSUITE_PNGS "${CMAKE_CURRENT_SOURCE_DIR}/contrib/pngsuite/*.png")
@@ -638,80 +787,96 @@
   set(PNGTEST_PNG "${CMAKE_CURRENT_SOURCE_DIR}/pngtest.png")
 
   add_executable(pngtest ${pngtest_sources})
-  target_link_libraries(pngtest png)
+  target_link_libraries(pngtest PRIVATE png_shared)
 
-  png_add_test(NAME pngtest COMMAND pngtest FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngtest
+               COMMAND pngtest
+               FILES "${PNGTEST_PNG}")
 
   add_executable(pngvalid ${pngvalid_sources})
-  target_link_libraries(pngvalid png)
+  target_link_libraries(pngvalid PRIVATE png_shared)
 
   png_add_test(NAME pngvalid-gamma-16-to-8
-               COMMAND pngvalid OPTIONS --gamma-16-to-8)
+               COMMAND pngvalid
+               OPTIONS --gamma-16-to-8)
   png_add_test(NAME pngvalid-gamma-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode)
+               COMMAND pngvalid
+               OPTIONS --gamma-alpha-mode)
   png_add_test(NAME pngvalid-gamma-background
-               COMMAND pngvalid OPTIONS --gamma-background)
+               COMMAND pngvalid
+               OPTIONS --gamma-background)
   png_add_test(NAME pngvalid-gamma-expand16-alpha-mode
-               COMMAND pngvalid OPTIONS --gamma-alpha-mode --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-alpha-mode --expand16)
   png_add_test(NAME pngvalid-gamma-expand16-background
-               COMMAND pngvalid OPTIONS --gamma-background --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-background --expand16)
   png_add_test(NAME pngvalid-gamma-expand16-transform
-               COMMAND pngvalid OPTIONS --gamma-transform --expand16)
+               COMMAND pngvalid
+               OPTIONS --gamma-transform --expand16)
   png_add_test(NAME pngvalid-gamma-sbit
-               COMMAND pngvalid OPTIONS --gamma-sbit)
+               COMMAND pngvalid
+               OPTIONS --gamma-sbit)
   png_add_test(NAME pngvalid-gamma-threshold
-               COMMAND pngvalid OPTIONS --gamma-threshold)
+               COMMAND pngvalid
+               OPTIONS --gamma-threshold)
   png_add_test(NAME pngvalid-gamma-transform
-               COMMAND pngvalid OPTIONS --gamma-transform)
+               COMMAND pngvalid
+               OPTIONS --gamma-transform)
   png_add_test(NAME pngvalid-progressive-interlace-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read --interlace)
+               COMMAND pngvalid
+               OPTIONS --standard --progressive-read --interlace)
   png_add_test(NAME pngvalid-progressive-size
-               COMMAND pngvalid OPTIONS --size --progressive-read)
+               COMMAND pngvalid
+               OPTIONS --size --progressive-read)
   png_add_test(NAME pngvalid-progressive-standard
-               COMMAND pngvalid OPTIONS --standard --progressive-read)
+               COMMAND pngvalid
+               OPTIONS --standard --progressive-read)
   png_add_test(NAME pngvalid-standard
-               COMMAND pngvalid OPTIONS --standard)
+               COMMAND pngvalid
+               OPTIONS --standard)
   png_add_test(NAME pngvalid-transform
-               COMMAND pngvalid OPTIONS --transform)
+               COMMAND pngvalid
+               OPTIONS --transform)
 
   add_executable(pngstest ${pngstest_sources})
-  target_link_libraries(pngstest png)
+  target_link_libraries(pngstest PRIVATE png_shared)
 
   foreach(gamma_type 1.8 linear none sRGB)
     foreach(alpha_type none alpha)
       set(PNGSTEST_FILES)
       foreach(test_png ${TEST_PNGS})
-        string(REGEX MATCH ".*-linear[-.].*" TEST_PNG_LINEAR "${test_png}")
-        string(REGEX MATCH ".*-sRGB[-.].*" TEST_PNG_SRGB "${test_png}")
-        string(REGEX MATCH ".*-1.8[-.].*" TEST_PNG_G18 "${test_png}")
-        string(REGEX MATCH ".*-alpha-.*" TEST_PNG_ALPHA "${test_png}")
+        string(REGEX MATCH "-linear[-.]" TEST_PNG_LINEAR "${test_png}")
+        string(REGEX MATCH "-sRGB[-.]" TEST_PNG_SRGB "${test_png}")
+        string(REGEX MATCH "-1.8[-.]" TEST_PNG_G18 "${test_png}")
+        string(REGEX MATCH "-alpha-" TEST_PNG_ALPHA "${test_png}")
 
         set(TEST_PNG_VALID TRUE)
 
         if(TEST_PNG_ALPHA)
-          if(NOT "${alpha_type}" STREQUAL "alpha")
+          if(NOT alpha_type STREQUAL "alpha")
             set(TEST_PNG_VALID FALSE)
           endif()
         else()
-          if("${alpha_type}" STREQUAL "alpha")
+          if(alpha_type STREQUAL "alpha")
             set(TEST_PNG_VALID FALSE)
           endif()
         endif()
 
         if(TEST_PNG_LINEAR)
-          if(NOT "${gamma_type}" STREQUAL "linear")
+          if(NOT gamma_type STREQUAL "linear")
             set(TEST_PNG_VALID FALSE)
           endif()
         elseif(TEST_PNG_SRGB)
-          if(NOT "${gamma_type}" STREQUAL "sRGB")
+          if(NOT gamma_type STREQUAL "sRGB")
             set(TEST_PNG_VALID FALSE)
           endif()
         elseif(TEST_PNG_G18)
-          if(NOT "${gamma_type}" STREQUAL "1.8")
+          if(NOT gamma_type STREQUAL "1.8")
             set(TEST_PNG_VALID FALSE)
           endif()
         else()
-          if(NOT "${gamma_type}" STREQUAL "none")
+          if(NOT gamma_type STREQUAL "none")
             set(TEST_PNG_VALID FALSE)
           endif()
         endif()
@@ -730,96 +895,131 @@
   endforeach()
 
   add_executable(pngunknown ${pngunknown_sources})
-  target_link_libraries(pngunknown png)
+  target_link_libraries(pngunknown PRIVATE png_shared)
 
-  png_add_test(NAME pngunknown-discard COMMAND pngunknown OPTIONS --strict default=discard FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-IDAT COMMAND pngunknown OPTIONS --strict default=discard IDAT=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-if-safe COMMAND pngunknown OPTIONS --strict default=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sAPI COMMAND pngunknown OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-save COMMAND pngunknown OPTIONS --strict default=save FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-sTER COMMAND pngunknown OPTIONS --strict sTER=if-safe FILES "${PNGTEST_PNG}")
-  png_add_test(NAME pngunknown-vpAg COMMAND pngunknown OPTIONS --strict vpAg=if-safe FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-discard
+               COMMAND pngunknown
+               OPTIONS --strict default=discard
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-IDAT
+               COMMAND pngunknown
+               OPTIONS --strict default=discard IDAT=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-if-safe
+               COMMAND pngunknown
+               OPTIONS --strict default=if-safe
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-sAPI
+               COMMAND pngunknown
+               OPTIONS --strict bKGD=save cHRM=save gAMA=save all=discard iCCP=save sBIT=save sRGB=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-save
+               COMMAND pngunknown
+               OPTIONS --strict default=save
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-sTER
+               COMMAND pngunknown
+               OPTIONS --strict sTER=if-safe
+               FILES "${PNGTEST_PNG}")
+  png_add_test(NAME pngunknown-vpAg
+               COMMAND pngunknown
+               OPTIONS --strict vpAg=if-safe
+               FILES "${PNGTEST_PNG}")
 
   add_executable(pngimage ${pngimage_sources})
-  target_link_libraries(pngimage png)
+  target_link_libraries(pngimage PRIVATE png_shared)
 
-  png_add_test(NAME pngimage-quick COMMAND pngimage OPTIONS --list-combos --log FILES ${PNGSUITE_PNGS})
-  png_add_test(NAME pngimage-full COMMAND pngimage OPTIONS --exhaustive --list-combos --log FILES ${PNGSUITE_PNGS})
+  png_add_test(NAME pngimage-quick
+               COMMAND pngimage
+               OPTIONS --list-combos --log
+               FILES ${PNGSUITE_PNGS})
+  png_add_test(NAME pngimage-full
+               COMMAND pngimage
+               OPTIONS --exhaustive --list-combos --log
+               FILES ${PNGSUITE_PNGS})
 endif()
 
-if(PNG_SHARED)
+if(PNG_SHARED AND PNG_TOOLS)
   add_executable(pngfix ${pngfix_sources})
-  target_link_libraries(pngfix png)
+  target_link_libraries(pngfix PRIVATE png_shared)
   set(PNG_BIN_TARGETS pngfix)
 
   add_executable(png-fix-itxt ${png_fix_itxt_sources})
-  target_link_libraries(png-fix-itxt ${ZLIB_LIBRARY} ${M_LIBRARY})
+  target_link_libraries(png-fix-itxt PRIVATE ZLIB::ZLIB ${M_LIBRARY})
   list(APPEND PNG_BIN_TARGETS png-fix-itxt)
 endif()
 
-# Set a variable with CMake code which:
-# Creates a symlink from src to dest (if possible) or alternatively
-# copies if different.
-include(CMakeParseArguments)
-
+# Create a symlink from src to dest (if possible), or, alternatively,
+# copy src to dest if different.
 function(create_symlink DEST_FILE)
-
-  cmake_parse_arguments(S "" "FILE;TARGET" "" ${ARGN})
-
-  if(NOT S_TARGET AND NOT S_FILE)
-    message(FATAL_ERROR "create_symlink: Missing TARGET or FILE argument")
+  cmake_parse_arguments(_SYM "" "FILE;TARGET" "" ${ARGN})
+  if(NOT _SYM_FILE AND NOT _SYM_TARGET)
+    message(FATAL_ERROR "create_symlink: Missing FILE or TARGET argument")
+  endif()
+  if(_SYM_FILE AND _SYM_TARGET)
+    message(FATAL_ERROR "create_symlink: "
+                        "The arguments FILE (${_SYM_FILE}) and TARGET (${_SYM_TARGET}) "
+                        "are mutually-exclusive")
   endif()
 
-  if(S_TARGET AND S_FILE)
-    message(FATAL_ERROR "create_symlink: Both source file ${S_FILE} and build target ${S_TARGET} arguments are present; can only have one.")
-  endif()
-
-  if(S_FILE)
+  if(_SYM_FILE)
     # If we don't need to symlink something that's coming from a build target,
     # we can go ahead and symlink/copy at configure time.
     if(CMAKE_HOST_WIN32 AND NOT CYGWIN)
-      execute_process(
-        COMMAND "${CMAKE_COMMAND}" -E copy_if_different ${S_FILE} ${DEST_FILE}
-        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
+      execute_process(COMMAND "${CMAKE_COMMAND}"
+                              -E copy_if_different
+                              ${_SYM_FILE} ${DEST_FILE}
+                      WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     else()
-      execute_process(
-        COMMAND ${CMAKE_COMMAND} -E create_symlink ${S_FILE} ${DEST_FILE}
-        WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
+      execute_process(COMMAND "${CMAKE_COMMAND}"
+                              -E create_symlink
+                              ${_SYM_FILE} ${DEST_FILE}
+                      WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     endif()
   endif()
 
-  if(S_TARGET)
-    # We need to use generator expressions, which can be a bit tricky, so for
-    # simplicity make the symlink a POST_BUILD step and use the TARGET
+  if(_SYM_TARGET)
+    # We need to use generator expressions, which can be a bit tricky.
+    # For simplicity, make the symlink a POST_BUILD step, and use the TARGET
     # signature of add_custom_command.
     if(CMAKE_HOST_WIN32 AND NOT CYGWIN)
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-        COMMAND "${CMAKE_COMMAND}" -E copy_if_different $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
+      add_custom_command(TARGET ${_SYM_TARGET}
+                         POST_BUILD
+                         COMMAND "${CMAKE_COMMAND}"
+                                 -E copy_if_different
+                                 $<TARGET_LINKER_FILE_DIR:${_SYM_TARGET}>/$<TARGET_LINKER_FILE_NAME:${_SYM_TARGET}>
+                                 $<TARGET_LINKER_FILE_DIR:${_SYM_TARGET}>/${DEST_FILE})
     else()
-      add_custom_command(TARGET ${S_TARGET} POST_BUILD
-        COMMAND "${CMAKE_COMMAND}" -E create_symlink $<TARGET_LINKER_FILE_NAME:${S_TARGET}> $<TARGET_LINKER_FILE_DIR:${S_TARGET}>/${DEST_FILE})
+      add_custom_command(TARGET ${_SYM_TARGET}
+                         POST_BUILD
+                         COMMAND "${CMAKE_COMMAND}"
+                                 -E create_symlink
+                                 $<TARGET_LINKER_FILE_NAME:${_SYM_TARGET}>
+                                 $<TARGET_LINKER_FILE_DIR:${_SYM_TARGET}>/${DEST_FILE})
     endif()
   endif()
-
 endfunction()
 
 # Create source generation scripts.
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genchk.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genchk.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/genout.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/genout.cmake @ONLY)
-configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/gensrc.cmake.in
-               ${CMAKE_CURRENT_BINARY_DIR}/scripts/gensrc.cmake @ONLY)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/cmake/genchk.cmake.in
+               ${CMAKE_CURRENT_BINARY_DIR}/genchk.cmake
+               @ONLY)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/cmake/genout.cmake.in
+               ${CMAKE_CURRENT_BINARY_DIR}/genout.cmake
+               @ONLY)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/cmake/gensrc.cmake.in
+               ${CMAKE_CURRENT_BINARY_DIR}/gensrc.cmake
+               @ONLY)
 
 # libpng is a library so default to 'lib'
 if(NOT DEFINED CMAKE_INSTALL_LIBDIR)
   set(CMAKE_INSTALL_LIBDIR lib)
 endif()
 
-# CREATE PKGCONFIG FILES
+# Create pkgconfig files.
 # We use the same files like ./configure, so we have to set its vars.
-# Only do this on Windows for Cygwin - the files don't make much sense outside
-# of a UNIX look-alike.
+# Only do this on Windows for Cygwin - the files don't make much sense
+# outside of a UNIX look-alike.
 if(NOT WIN32 OR CYGWIN OR MINGW)
   set(prefix      ${CMAKE_INSTALL_PREFIX})
   set(exec_prefix ${CMAKE_INSTALL_PREFIX})
@@ -827,43 +1027,29 @@
   set(includedir  ${CMAKE_INSTALL_FULL_INCLUDEDIR})
   set(LIBS        "-lz -lm")
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng.pc.in
-    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc @ONLY)
-  create_symlink(libpng.pc FILE ${PNGLIB_NAME}.pc)
-
+                 ${CMAKE_CURRENT_BINARY_DIR}/libpng${PNGLIB_ABI_VERSION}.pc
+                 @ONLY)
+  create_symlink(libpng.pc FILE libpng${PNGLIB_ABI_VERSION}.pc)
   configure_file(${CMAKE_CURRENT_SOURCE_DIR}/libpng-config.in
-    ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config @ONLY)
-  create_symlink(libpng-config FILE ${PNGLIB_NAME}-config)
+                 ${CMAKE_CURRENT_BINARY_DIR}/libpng${PNGLIB_ABI_VERSION}-config
+                 @ONLY)
+  create_symlink(libpng-config FILE libpng${PNGLIB_ABI_VERSION}-config)
 endif()
 
-# SET UP LINKS
-if(PNG_SHARED)
-  set_target_properties(png PROPERTIES
-    VERSION 16.${PNGLIB_RELEASE}.git
-#   VERSION 16.${PNGLIB_RELEASE}.0
-    SOVERSION 16
-    CLEAN_DIRECT_OUTPUT 1)
-endif()
-
-# INSTALL
+# Install.
 if(NOT SKIP_INSTALL_LIBRARIES AND NOT SKIP_INSTALL_ALL)
-  install(TARGETS ${PNG_LIB_TARGETS}
+  install(TARGETS ${PNG_LIBRARY_TARGETS}
           EXPORT libpng
-          RUNTIME DESTINATION bin
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
           LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
           ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
           FRAMEWORK DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
   if(PNG_SHARED)
     # Create a symlink for libpng.dll.a => libpng16.dll.a on Cygwin
-    if(CYGWIN OR MINGW)
-      create_symlink(libpng${CMAKE_IMPORT_LIBRARY_SUFFIX} TARGET png)
-      install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_IMPORT_LIBRARY_SUFFIX}
-              DESTINATION ${CMAKE_INSTALL_LIBDIR})
-    endif()
-
-    if(NOT WIN32)
-      create_symlink(libpng${CMAKE_SHARED_LIBRARY_SUFFIX} TARGET png)
-      install(FILES $<TARGET_LINKER_FILE_DIR:png>/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
+    if(NOT WIN32 OR CYGWIN OR MINGW)
+      create_symlink(libpng${CMAKE_SHARED_LIBRARY_SUFFIX} TARGET png_shared)
+      install(FILES $<TARGET_LINKER_FILE_DIR:png_shared>/libpng${CMAKE_SHARED_LIBRARY_SUFFIX}
               DESTINATION ${CMAKE_INSTALL_LIBDIR})
     endif()
   endif()
@@ -878,54 +1064,51 @@
 endif()
 
 if(NOT SKIP_INSTALL_HEADERS AND NOT SKIP_INSTALL_ALL)
-  install(FILES ${libpng_public_hdrs} DESTINATION include)
-  install(FILES ${libpng_public_hdrs} DESTINATION include/${PNGLIB_NAME})
+  install(FILES ${libpng_public_hdrs}
+          DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+  install(FILES ${libpng_public_hdrs}
+          DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/libpng${PNGLIB_ABI_VERSION})
 endif()
 if(NOT SKIP_INSTALL_EXECUTABLES AND NOT SKIP_INSTALL_ALL)
   if(NOT WIN32 OR CYGWIN OR MINGW)
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config DESTINATION bin)
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config DESTINATION bin)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng${PNGLIB_ABI_VERSION}-config
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
   endif()
 endif()
 
 if(NOT SKIP_INSTALL_PROGRAMS AND NOT SKIP_INSTALL_ALL)
   install(TARGETS ${PNG_BIN_TARGETS}
-          RUNTIME DESTINATION bin)
+          RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
 endif()
 
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL)
-  # Install man pages
-  if(NOT PNG_MAN_DIR)
-    set(PNG_MAN_DIR "share/man")
-  endif()
-  install(FILES libpng.3 libpngpf.3 DESTINATION ${PNG_MAN_DIR}/man3)
-  install(FILES png.5 DESTINATION ${PNG_MAN_DIR}/man5)
-  # Install pkg-config files
+  # Install the man pages.
+  install(FILES libpng.3 libpngpf.3
+          DESTINATION ${CMAKE_INSTALL_MANDIR}/man3)
+  install(FILES png.5
+          DESTINATION ${CMAKE_INSTALL_MANDIR}/man5)
+  # Install the pkg-config files.
   if(NOT CMAKE_HOST_WIN32 OR CYGWIN OR MINGW)
     install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng.pc
             DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
     install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng-config
-            DESTINATION bin)
-    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}.pc
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libpng${PNGLIB_ABI_VERSION}.pc
             DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${PNGLIB_NAME}-config
-            DESTINATION bin)
+    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/libpng${PNGLIB_ABI_VERSION}-config
+            DESTINATION ${CMAKE_INSTALL_BINDIR})
   endif()
 endif()
 
 # Create an export file that CMake users can include() to import our targets.
 if(NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL)
-  install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
+  install(EXPORT libpng
+          DESTINATION ${CMAKE_INSTALL_LIBDIR}/libpng
+          FILE libpng${PNGLIB_ABI_VERSION}.cmake)
 endif()
 
-# what's with libpng-manual.txt and all the extra files?
-
-# UNINSTALL
-# do we need this?
-
-# DIST
-# do we need this?
-
-# to create msvc import lib for mingw compiled shared lib
+# TODO: Create MSVC import lib for MinGW-compiled shared lib.
 # pexports libpng.dll > libpng.def
 # lib /def:libpng.def /machine:x86
diff --git a/INSTALL b/INSTALL
index 4c17022..042d729 100644
--- a/INSTALL
+++ b/INSTALL
@@ -128,16 +128,18 @@
           README
           *.h, *.c  => libpng source files
           CMakeLists.txt    =>  "cmake" script
+          ci
+             ci_*.sh
           configuration files:
              configure.ac, configure, Makefile.am, Makefile.in,
              autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
              libpng-config.in, aclocal.m4, config.h.in, config.sub,
-             depcomp, install-sh, mkinstalldirs, test-pngtest.sh
+             depcomp, install-sh, mkinstalldirs, test-pngtest.sh, etc.
           contrib
              arm-neon, conftest, examples, gregbook, libtests, pngminim,
              pngminus, pngsuite, tools, visupng
           projects
-             cbuilder5, owatcom, visualc71, vstudio, xcode
+             owatcom, visualc71, vstudio
           scripts
              makefile.*
              *.def (module definition files)
@@ -145,7 +147,7 @@
           pngtest.png
           etc.
       zlib
-          README, *.h, *.c contrib, etc.
+          README, *.h, *.c, contrib, etc.
 
 If the line endings in the files look funny, you may wish to get the other
 distribution of libpng.  It is available in both tar.gz (UNIX style line
@@ -153,28 +155,27 @@
 
 VI. Building with project files
 
-If you are building libpng with MSVC, you can enter the
-libpng projects\visualc71 or vstudio directory and follow the instructions
-in README.txt.
+If you are building libpng with Microsoft Visual Studio, you can enter
+the directory projects\visualc71 or projects\vstudio and follow the
+instructions in README.txt.
 
-Otherwise enter the zlib directory and follow the instructions in zlib/README,
-then come back here and run "configure" or choose the appropriate
-makefile.sys in the scripts directory.
+Otherwise, enter the zlib directory and follow the instructions in
+zlib/README, then come back here and run "configure" or choose the
+appropriate makefile in the scripts directory.
 
 VII. Building with makefiles
 
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example
 
-MSDOS example:
-
-    copy scripts\makefile.msc makefile
-    copy scripts\pnglibconf.h.prebuilt pnglibconf.h
-
 UNIX example:
 
-    cp scripts/makefile.std makefile
-    cp scripts/pnglibconf.h.prebuilt pnglibconf.h
+    cp scripts/makefile.std Makefile
+    make
+
+Windows example:
+
+    nmake -f scripts\makefile.vcwin32
 
 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
@@ -191,36 +192,33 @@
 Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare
 your output with the result shown in contrib/pngsuite/README.
 
-Most of the makefiles will allow you to run "make install" to
-put the library in its final resting place (if you want to
-do that, run "make install" in the zlib directory first if necessary).
-Some also allow you to run "make test-installed" after you have
-run "make install".
+Most of the makefiles used to allow you to run "make install" to put
+the library in its final resting place, but that feature is no longer
+supported.  The only tested and supported manners to install libpng are
+the conventional build and install procedures driven by the configure
+script or by the CMake file.
 
-VIII. Configuring libpng for 16-bit platforms
+VIII. Configuring for DOS and other 16-bit platforms
 
-You will want to look into zconf.h to tell zlib (and thus libpng) that
-it cannot allocate more than 64K at a time.  Even if you can, the memory
-won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
-
-IX. Configuring for DOS
+Officially, the support for 16-bit platforms has been removed.
 
 For DOS users who only have access to the lower 640K, you will
 have to limit zlib's memory usage via a png_set_compression_mem_level()
 call.  See zlib.h or zconf.h in the zlib library for more information.
 
-X. Configuring for Medium Model
+You may be or may not be in luck if you target the "large" memory model,
+but all the smaller models ("small", "compact" and "medium") are known
+to be unworkable.  For DOS users who have access beyond the lower 640K,
+a "flat" 32-bit DOS model (such as DJGPP) is strongly recommended.
 
-Libpng's support for medium model has been tested on most of the popular
-compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
-defined, and FAR gets defined to far in pngconf.h, and you should be
-all set.  Everything in the library (except for zlib's structure) is
-expecting far data.  You must use the typedefs with the p or pp on
-the end for pointers (or at least look at them and be careful).  Make
-note that the rows of data are defined as png_bytepp, which is
-an "unsigned char far * far *".
+For DOS users who only have access to the lower 640K, you will have to
+limit zlib's memory usage via a png_set_compression_mem_level() call.
+You will also have to look into zconf.h to tell zlib (and thus libpng)
+that it cannot allocate more than 64K at a time.  Even if you can, the
+memory won't be accessible.  Therefore, you should limit zlib and libpng
+to 64K by defining MAXSEG_64K.
 
-XI. Prepending a prefix to exported symbols
+IX. Prepending a prefix to exported symbols
 
 Starting with libpng-1.6.0, you can configure libpng (when using the
 "configure" script) to prefix all exported symbols by means of the
@@ -231,7 +229,7 @@
 transparent to applications; their function calls get transformed by
 the macros to use the modified names.
 
-XII. Configuring for compiler xxx:
+X. Configuring for compiler xxx:
 
 All includes for libpng are in pngconf.h.  If you need to add, change
 or delete an include, this is the place to do it.
@@ -243,7 +241,7 @@
 files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
 that previously appeared in the public headers.
 
-XIII. Removing unwanted object code
+XI. Removing unwanted object code
 
 There are a bunch of #define's in pngconf.h that control what parts of
 libpng are compiled.  All the defines end in _SUPPORTED.  If you are
@@ -282,7 +280,7 @@
 The size of the library itself should not be an issue, because only
 those sections that are actually used will be loaded into memory.
 
-XIV. Enabling or disabling hardware optimizations
+XII. Enabling or disabling hardware optimizations
 
 Certain hardware capabilities, such as the Intel SSE instructions,
 are normally detected at run time. Enable them with configure options
@@ -332,7 +330,7 @@
 
     cmake . -DPNG_HARDWARE_OPTIMIZATIONS=no
 
-XV. Changes to the build and configuration of libpng in libpng-1.5.x
+XIII. Changes to the build and configuration of libpng in libpng-1.5.x
 
 Details of internal changes to the library code can be found in the CHANGES
 file and in the GIT repository logs.  These will be of no concern to the vast
@@ -423,7 +421,7 @@
 libpng, because than the settings would not accurately reflect the settings
 that were used to build libpng.
 
-XVI. Setjmp/longjmp issues
+XIV. Setjmp/longjmp issues
 
 Libpng uses setjmp()/longjmp() for error handling.  Unfortunately setjmp()
 is known to be not thread-safe on some platforms and we don't know of
@@ -441,7 +439,7 @@
 with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
 and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
 
-XVII. Common linking failures
+XV. Common linking failures
 
 If your application fails to find libpng or zlib entries while linking:
 
@@ -453,12 +451,13 @@
   If you are using the vstudio project, observe the WARNING in
   project/vstudio/README.txt.
 
-XVIII. Other sources of information about libpng:
+XVI. Other sources of information about libpng:
 
 Further information can be found in the README and libpng-manual.txt
 files, in the individual makefiles, in png.h, and the manual pages
 libpng.3 and png.5.
 
+Copyright (c) 2022 Cosmin Truta
 Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
 This document is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
diff --git a/LICENSE b/LICENSE
index e0c5b53..25f298f 100644
--- a/LICENSE
+++ b/LICENSE
@@ -4,8 +4,8 @@
 PNG Reference Library License version 2
 ---------------------------------------
 
- * Copyright (c) 1995-2019 The PNG Reference Library Authors.
- * Copyright (c) 2018-2019 Cosmin Truta.
+ * Copyright (c) 1995-2024 The PNG Reference Library Authors.
+ * Copyright (c) 2018-2024 Cosmin Truta.
  * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  * Copyright (c) 1996-1997 Andreas Dilger.
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
diff --git a/Makefile.am b/Makefile.am
index f21107e..1f06c70 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,6 @@
 # Makefile.am, the source file for Makefile.in (and hence Makefile), is
 #
-# Copyright (c) 2018 Cosmin Truta
+# Copyright (c) 2018-2024 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
@@ -9,16 +9,24 @@
 
 PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 
-ACLOCAL_AMFLAGS = -I scripts
+ACLOCAL_AMFLAGS = -I scripts/autoconf
 
 # test programs - run on make check, make distcheck
+if ENABLE_TESTS
 check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage pngcp
 if HAVE_CLOCK_GETTIME
 check_PROGRAMS += timepng
 endif
+else
+check_PROGRAMS=
+endif
 
 # Utilities - installed
+if ENABLE_TOOLS
 bin_PROGRAMS= pngfix png-fix-itxt
+else
+bin_PROGRAMS=
+endif
 
 # This ensures that pnglibconf.h gets built at the start of 'make all' or
 # 'make check', but it does not add dependencies to the individual programs,
@@ -30,6 +38,7 @@
 # always wrong and always very confusing.
 BUILT_SOURCES = pnglibconf.h
 
+if ENABLE_TESTS
 pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 
@@ -48,16 +57,20 @@
 timepng_SOURCES = contrib/libtests/timepng.c
 timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 
+pngcp_SOURCES = contrib/tools/pngcp.c
+pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+endif
+
+if ENABLE_TOOLS
 pngfix_SOURCES = contrib/tools/pngfix.c
 pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 
 png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
-
-pngcp_SOURCES = contrib/tools/pngcp.c
-pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+endif
 
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
+if ENABLE_TESTS
 TESTS =\
    tests/pngtest-all\
    tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
@@ -75,6 +88,7 @@
    tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
    tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
    tests/pngimage-quick tests/pngimage-full
+endif
 
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5
@@ -103,6 +117,13 @@
 	mips/filter_msa_intrinsics.c
 endif
 
+if PNG_MIPS_MMI
+if !PNG_MIPS_MSA
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/mips_init.c
+endif
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/filter_mmi_inline_assembly.c
+endif
+
 if PNG_INTEL_SSE
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += intel/intel_init.c\
 	intel/filter_sse2_intrinsics.c
@@ -113,6 +134,15 @@
         powerpc/filter_vsx_intrinsics.c
 endif
 
+if PNG_LOONGARCH_LSX
+noinst_LTLIBRARIES= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES = loongarch/loongarch_lsx_init.c\
+	loongarch/filter_lsx_intrinsics.c
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS = -mlsx
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+# libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+endif
+
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
 
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
@@ -133,6 +163,10 @@
   libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
 endif
 
+if PNG_LOONGARCH_LSX
+  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES += libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+endif
+
 #distribute headers in /usr/include/libpng/*
 pkgincludedir= $(includedir)/$(PNGLIB_BASENAME)
 pkginclude_HEADERS= png.h pngconf.h
@@ -149,7 +183,7 @@
 EXTRA_DIST= \
 	ANNOUNCE AUTHORS CHANGES INSTALL LICENSE README TODO TRADEMARK \
 	pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
-	${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
+	${srcdir}/ci ${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
 	$(TESTS) $(XFAIL_TESTS) tests/pngstest \
 	CMakeLists.txt example.c libpng-manual.txt
 
diff --git a/Makefile.in b/Makefile.in
index 31a82d2..c9eac7d 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.1 from Makefile.am.
+# Makefile.in generated by automake 1.16.5 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2018 Free Software Foundation, Inc.
+# Copyright (C) 1994-2021 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -16,7 +16,7 @@
 
 # Makefile.am, the source file for Makefile.in (and hence Makefile), is
 #
-# Copyright (c) 2018 Cosmin Truta
+# Copyright (c) 2018-2024 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
@@ -100,11 +100,13 @@
 POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
-check_PROGRAMS = pngtest$(EXEEXT) pngunknown$(EXEEXT) \
-	pngstest$(EXEEXT) pngvalid$(EXEEXT) pngimage$(EXEEXT) \
-	pngcp$(EXEEXT) $(am__EXEEXT_1)
-@HAVE_CLOCK_GETTIME_TRUE@am__append_1 = timepng
-bin_PROGRAMS = pngfix$(EXEEXT) png-fix-itxt$(EXEEXT)
+@ENABLE_TESTS_TRUE@check_PROGRAMS = pngtest$(EXEEXT) \
+@ENABLE_TESTS_TRUE@	pngunknown$(EXEEXT) pngstest$(EXEEXT) \
+@ENABLE_TESTS_TRUE@	pngvalid$(EXEEXT) pngimage$(EXEEXT) \
+@ENABLE_TESTS_TRUE@	pngcp$(EXEEXT) $(am__EXEEXT_1)
+@ENABLE_TESTS_TRUE@@HAVE_CLOCK_GETTIME_TRUE@am__append_1 = timepng
+@ENABLE_TOOLS_TRUE@bin_PROGRAMS = pngfix$(EXEEXT) \
+@ENABLE_TOOLS_TRUE@	png-fix-itxt$(EXEEXT)
 @PNG_ARM_NEON_TRUE@am__append_2 = arm/arm_init.c\
 @PNG_ARM_NEON_TRUE@	arm/filter_neon.S arm/filter_neon_intrinsics.c \
 @PNG_ARM_NEON_TRUE@	arm/palette_neon_intrinsics.c
@@ -112,26 +114,29 @@
 @PNG_MIPS_MSA_TRUE@am__append_3 = mips/mips_init.c\
 @PNG_MIPS_MSA_TRUE@	mips/filter_msa_intrinsics.c
 
-@PNG_INTEL_SSE_TRUE@am__append_4 = intel/intel_init.c\
+@PNG_MIPS_MMI_TRUE@@PNG_MIPS_MSA_FALSE@am__append_4 = mips/mips_init.c
+@PNG_MIPS_MMI_TRUE@am__append_5 = mips/filter_mmi_inline_assembly.c
+@PNG_INTEL_SSE_TRUE@am__append_6 = intel/intel_init.c\
 @PNG_INTEL_SSE_TRUE@	intel/filter_sse2_intrinsics.c
 
-@PNG_POWERPC_VSX_TRUE@am__append_5 = powerpc/powerpc_init.c\
+@PNG_POWERPC_VSX_TRUE@am__append_7 = powerpc/powerpc_init.c\
 @PNG_POWERPC_VSX_TRUE@        powerpc/filter_vsx_intrinsics.c
 
 
 #   Versioned symbols and restricted exports
-@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_TRUE@am__append_6 = -Wl,-M -Wl,libpng.vers
-@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_FALSE@am__append_7 = -Wl,--version-script=libpng.vers
+@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_TRUE@am__append_8 = -Wl,-M -Wl,libpng.vers
+@HAVE_LD_VERSION_SCRIPT_TRUE@@HAVE_SOLARIS_LD_FALSE@am__append_9 = -Wl,--version-script=libpng.vers
 #   Only restricted exports when possible
-@HAVE_LD_VERSION_SCRIPT_FALSE@am__append_8 = -export-symbols libpng.sym
-@DO_PNG_PREFIX_TRUE@am__append_9 = -DPNG_PREFIX='@PNG_PREFIX@'
+@HAVE_LD_VERSION_SCRIPT_FALSE@am__append_10 = -export-symbols libpng.sym
+@PNG_LOONGARCH_LSX_TRUE@am__append_11 = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+@DO_PNG_PREFIX_TRUE@am__append_12 = -DPNG_PREFIX='@PNG_PREFIX@'
 subdir = .
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
-am__aclocal_m4_deps = $(top_srcdir)/scripts/libtool.m4 \
-	$(top_srcdir)/scripts/ltoptions.m4 \
-	$(top_srcdir)/scripts/ltsugar.m4 \
-	$(top_srcdir)/scripts/ltversion.m4 \
-	$(top_srcdir)/scripts/lt~obsolete.m4 \
+am__aclocal_m4_deps = $(top_srcdir)/scripts/autoconf/libtool.m4 \
+	$(top_srcdir)/scripts/autoconf/ltoptions.m4 \
+	$(top_srcdir)/scripts/autoconf/ltsugar.m4 \
+	$(top_srcdir)/scripts/autoconf/ltversion.m4 \
+	$(top_srcdir)/scripts/autoconf/lt~obsolete.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
@@ -147,7 +152,8 @@
 	"$(DESTDIR)$(bindir)" "$(DESTDIR)$(man3dir)" \
 	"$(DESTDIR)$(man5dir)" "$(DESTDIR)$(pkgconfigdir)" \
 	"$(DESTDIR)$(pkgincludedir)" "$(DESTDIR)$(pkgincludedir)"
-@HAVE_CLOCK_GETTIME_TRUE@am__EXEEXT_1 = timepng$(EXEEXT)
+@ENABLE_TESTS_TRUE@@HAVE_CLOCK_GETTIME_TRUE@am__EXEEXT_1 =  \
+@ENABLE_TESTS_TRUE@@HAVE_CLOCK_GETTIME_TRUE@	timepng$(EXEEXT)
 PROGRAMS = $(bin_PROGRAMS)
 am__vpath_adj_setup = srcdirstrip=`echo "$(srcdir)" | sed 's|.|.|g'`;
 am__vpath_adj = case $$p in \
@@ -176,8 +182,7 @@
     || { echo " ( cd '$$dir' && rm -f" $$files ")"; \
          $(am__cd) "$$dir" && rm -f $$files; }; \
   }
-LTLIBRARIES = $(lib_LTLIBRARIES)
-libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD =
+LTLIBRARIES = $(lib_LTLIBRARIES) $(noinst_LTLIBRARIES)
 am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES_DIST = png.c \
 	pngerror.c pngget.c pngmem.c pngpread.c pngread.c pngrio.c \
 	pngrtran.c pngrutil.c pngset.c pngtrans.c pngwio.c pngwrite.c \
@@ -185,24 +190,28 @@
 	pngpriv.h pngstruct.h pngusr.dfa arm/arm_init.c \
 	arm/filter_neon.S arm/filter_neon_intrinsics.c \
 	arm/palette_neon_intrinsics.c mips/mips_init.c \
-	mips/filter_msa_intrinsics.c intel/intel_init.c \
-	intel/filter_sse2_intrinsics.c powerpc/powerpc_init.c \
-	powerpc/filter_vsx_intrinsics.c
+	mips/filter_msa_intrinsics.c mips/filter_mmi_inline_assembly.c \
+	intel/intel_init.c intel/filter_sse2_intrinsics.c \
+	powerpc/powerpc_init.c powerpc/filter_vsx_intrinsics.c
 am__dirstamp = $(am__leading_dot)dirstamp
 @PNG_ARM_NEON_TRUE@am__objects_1 = arm/arm_init.lo arm/filter_neon.lo \
 @PNG_ARM_NEON_TRUE@	arm/filter_neon_intrinsics.lo \
 @PNG_ARM_NEON_TRUE@	arm/palette_neon_intrinsics.lo
 @PNG_MIPS_MSA_TRUE@am__objects_2 = mips/mips_init.lo \
 @PNG_MIPS_MSA_TRUE@	mips/filter_msa_intrinsics.lo
-@PNG_INTEL_SSE_TRUE@am__objects_3 = intel/intel_init.lo \
+@PNG_MIPS_MMI_TRUE@@PNG_MIPS_MSA_FALSE@am__objects_3 =  \
+@PNG_MIPS_MMI_TRUE@@PNG_MIPS_MSA_FALSE@	mips/mips_init.lo
+@PNG_MIPS_MMI_TRUE@am__objects_4 = mips/filter_mmi_inline_assembly.lo
+@PNG_INTEL_SSE_TRUE@am__objects_5 = intel/intel_init.lo \
 @PNG_INTEL_SSE_TRUE@	intel/filter_sse2_intrinsics.lo
-@PNG_POWERPC_VSX_TRUE@am__objects_4 = powerpc/powerpc_init.lo \
+@PNG_POWERPC_VSX_TRUE@am__objects_6 = powerpc/powerpc_init.lo \
 @PNG_POWERPC_VSX_TRUE@	powerpc/filter_vsx_intrinsics.lo
 am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS = png.lo pngerror.lo \
 	pngget.lo pngmem.lo pngpread.lo pngread.lo pngrio.lo \
 	pngrtran.lo pngrutil.lo pngset.lo pngtrans.lo pngwio.lo \
 	pngwrite.lo pngwtran.lo pngwutil.lo $(am__objects_1) \
-	$(am__objects_2) $(am__objects_3) $(am__objects_4)
+	$(am__objects_2) $(am__objects_3) $(am__objects_4) \
+	$(am__objects_5) $(am__objects_6)
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS =  \
 	$(am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS) \
@@ -216,33 +225,69 @@
 	$(CCLD) $(AM_CFLAGS) $(CFLAGS) \
 	$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS) $(LDFLAGS) -o \
 	$@
-am_png_fix_itxt_OBJECTS = contrib/tools/png-fix-itxt.$(OBJEXT)
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_LIBADD =
+am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES_DIST =  \
+	loongarch/loongarch_lsx_init.c \
+	loongarch/filter_lsx_intrinsics.c
+@PNG_LOONGARCH_LSX_TRUE@am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_OBJECTS = loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo \
+@PNG_LOONGARCH_LSX_TRUE@	loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_OBJECTS =  \
+	$(am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_OBJECTS)
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_LINK = $(LIBTOOL) $(AM_V_lt) \
+	--tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=link \
+	$(CCLD) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS) \
+	$(CFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
+@PNG_LOONGARCH_LSX_TRUE@am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_rpath =
+am__png_fix_itxt_SOURCES_DIST = contrib/tools/png-fix-itxt.c
+@ENABLE_TOOLS_TRUE@am_png_fix_itxt_OBJECTS =  \
+@ENABLE_TOOLS_TRUE@	contrib/tools/png-fix-itxt.$(OBJEXT)
 png_fix_itxt_OBJECTS = $(am_png_fix_itxt_OBJECTS)
 png_fix_itxt_LDADD = $(LDADD)
-am_pngcp_OBJECTS = contrib/tools/pngcp.$(OBJEXT)
+am__pngcp_SOURCES_DIST = contrib/tools/pngcp.c
+@ENABLE_TESTS_TRUE@am_pngcp_OBJECTS = contrib/tools/pngcp.$(OBJEXT)
 pngcp_OBJECTS = $(am_pngcp_OBJECTS)
-pngcp_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngfix_OBJECTS = contrib/tools/pngfix.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngcp_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngfix_SOURCES_DIST = contrib/tools/pngfix.c
+@ENABLE_TOOLS_TRUE@am_pngfix_OBJECTS = contrib/tools/pngfix.$(OBJEXT)
 pngfix_OBJECTS = $(am_pngfix_OBJECTS)
-pngfix_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngimage_OBJECTS = contrib/libtests/pngimage.$(OBJEXT)
+@ENABLE_TOOLS_TRUE@pngfix_DEPENDENCIES =  \
+@ENABLE_TOOLS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngimage_SOURCES_DIST = contrib/libtests/pngimage.c
+@ENABLE_TESTS_TRUE@am_pngimage_OBJECTS =  \
+@ENABLE_TESTS_TRUE@	contrib/libtests/pngimage.$(OBJEXT)
 pngimage_OBJECTS = $(am_pngimage_OBJECTS)
-pngimage_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngstest_OBJECTS = contrib/libtests/pngstest.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngimage_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngstest_SOURCES_DIST = contrib/libtests/pngstest.c
+@ENABLE_TESTS_TRUE@am_pngstest_OBJECTS =  \
+@ENABLE_TESTS_TRUE@	contrib/libtests/pngstest.$(OBJEXT)
 pngstest_OBJECTS = $(am_pngstest_OBJECTS)
-pngstest_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngtest_OBJECTS = pngtest.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngstest_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngtest_SOURCES_DIST = pngtest.c
+@ENABLE_TESTS_TRUE@am_pngtest_OBJECTS = pngtest.$(OBJEXT)
 pngtest_OBJECTS = $(am_pngtest_OBJECTS)
-pngtest_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngunknown_OBJECTS = contrib/libtests/pngunknown.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngtest_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngunknown_SOURCES_DIST = contrib/libtests/pngunknown.c
+@ENABLE_TESTS_TRUE@am_pngunknown_OBJECTS =  \
+@ENABLE_TESTS_TRUE@	contrib/libtests/pngunknown.$(OBJEXT)
 pngunknown_OBJECTS = $(am_pngunknown_OBJECTS)
-pngunknown_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_pngvalid_OBJECTS = contrib/libtests/pngvalid.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngunknown_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__pngvalid_SOURCES_DIST = contrib/libtests/pngvalid.c
+@ENABLE_TESTS_TRUE@am_pngvalid_OBJECTS =  \
+@ENABLE_TESTS_TRUE@	contrib/libtests/pngvalid.$(OBJEXT)
 pngvalid_OBJECTS = $(am_pngvalid_OBJECTS)
-pngvalid_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-am_timepng_OBJECTS = contrib/libtests/timepng.$(OBJEXT)
+@ENABLE_TESTS_TRUE@pngvalid_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+am__timepng_SOURCES_DIST = contrib/libtests/timepng.c
+@ENABLE_TESTS_TRUE@am_timepng_OBJECTS =  \
+@ENABLE_TESTS_TRUE@	contrib/libtests/timepng.$(OBJEXT)
 timepng_OBJECTS = $(am_timepng_OBJECTS)
-timepng_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@timepng_DEPENDENCIES =  \
+@ENABLE_TESTS_TRUE@	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 SCRIPTS = $(bin_SCRIPTS)
 AM_V_P = $(am__v_P_@AM_V@)
 am__v_P_ = $(am__v_P_@AM_DEFAULT_V@)
@@ -280,6 +325,9 @@
 	contrib/tools/$(DEPDIR)/pngfix.Po \
 	intel/$(DEPDIR)/filter_sse2_intrinsics.Plo \
 	intel/$(DEPDIR)/intel_init.Plo \
+	loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Plo \
+	loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Plo \
+	mips/$(DEPDIR)/filter_mmi_inline_assembly.Plo \
 	mips/$(DEPDIR)/filter_msa_intrinsics.Plo \
 	mips/$(DEPDIR)/mips_init.Plo \
 	powerpc/$(DEPDIR)/filter_vsx_intrinsics.Plo \
@@ -315,14 +363,18 @@
 am__v_CCLD_1 = 
 SOURCES = $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES) \
 	$(nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES) \
+	$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES) \
 	$(png_fix_itxt_SOURCES) $(pngcp_SOURCES) $(pngfix_SOURCES) \
 	$(pngimage_SOURCES) $(pngstest_SOURCES) $(pngtest_SOURCES) \
 	$(pngunknown_SOURCES) $(pngvalid_SOURCES) $(timepng_SOURCES)
 DIST_SOURCES =  \
 	$(am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES_DIST) \
-	$(png_fix_itxt_SOURCES) $(pngcp_SOURCES) $(pngfix_SOURCES) \
-	$(pngimage_SOURCES) $(pngstest_SOURCES) $(pngtest_SOURCES) \
-	$(pngunknown_SOURCES) $(pngvalid_SOURCES) $(timepng_SOURCES)
+	$(am__libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES_DIST) \
+	$(am__png_fix_itxt_SOURCES_DIST) $(am__pngcp_SOURCES_DIST) \
+	$(am__pngfix_SOURCES_DIST) $(am__pngimage_SOURCES_DIST) \
+	$(am__pngstest_SOURCES_DIST) $(am__pngtest_SOURCES_DIST) \
+	$(am__pngunknown_SOURCES_DIST) $(am__pngvalid_SOURCES_DIST) \
+	$(am__timepng_SOURCES_DIST)
 am__can_run_installinfo = \
   case $$AM_UPDATE_INFO_DIR in \
     n|no|NO) false;; \
@@ -334,8 +386,8 @@
 MANS = $(dist_man_MANS)
 DATA = $(pkgconfig_DATA)
 HEADERS = $(nodist_pkginclude_HEADERS) $(pkginclude_HEADERS)
-am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) \
-	$(LISP)config.h.in
+am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP) \
+	config.h.in
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
 # *not* preserved.
@@ -352,9 +404,6 @@
   unique=`for i in $$list; do \
     if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
   done | $(am__uniquify_input)`
-ETAGS = etags
-CTAGS = ctags
-CSCOPE = cscope
 AM_RECURSIVE_TARGETS = cscope check recheck
 am__tty_colors_dummy = \
   mgn= red= grn= lgn= blu= brg= std=; \
@@ -511,6 +560,7 @@
   bases='$(TEST_LOGS)'; \
   bases=`for i in $$bases; do echo $$i; done | sed 's/\.log$$//'`; \
   bases=`echo $$bases`
+AM_TESTSUITE_SUMMARY_HEADER = ' for $(PACKAGE_STRING)'
 RECHECK_LOGS = $(TEST_LOGS)
 TEST_SUITE_LOG = test-suite.log
 TEST_EXTENSIONS = @EXEEXT@ .test
@@ -550,6 +600,8 @@
 DIST_ARCHIVES = $(distdir).tar.gz $(distdir).tar.xz
 GZIP_ENV = --best
 DIST_TARGETS = dist-xz dist-gzip
+# Exists only to be overridden by the user if desired.
+AM_DISTCHECK_DVI_TARGET = dvi
 distuninstallcheck_listfiles = find . -type f -print
 am__distuninstallcheck_listfiles = $(distuninstallcheck_listfiles) \
   | sed 's|^\./|$(prefix)/|' | grep -v '$(infodir)/dir$$'
@@ -574,6 +626,8 @@
 CFLAGS = @CFLAGS@
 CPP = @CPP@
 CPPFLAGS = @CPPFLAGS@
+CSCOPE = @CSCOPE@
+CTAGS = @CTAGS@
 CYGPATH_W = @CYGPATH_W@
 DEFS = @DEFS@
 DEPDIR = @DEPDIR@
@@ -591,8 +645,10 @@
 ECHO_N = @ECHO_N@
 ECHO_T = @ECHO_T@
 EGREP = @EGREP@
+ETAGS = @ETAGS@
 EXEEXT = @EXEEXT@
 FGREP = @FGREP@
+FILECMD = @FILECMD@
 GREP = @GREP@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
@@ -636,7 +692,6 @@
 # AM_CFLAGS)
 PNG_COPTS = @PNG_COPTS@
 PNG_PREFIX = @PNG_PREFIX@
-POW_LIB = @POW_LIB@
 RANLIB = @RANLIB@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
@@ -695,6 +750,7 @@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
+runstatedir = @runstatedir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 srcdir = @srcdir@
@@ -704,7 +760,7 @@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 PNGLIB_BASENAME = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
-ACLOCAL_AMFLAGS = -I scripts
+ACLOCAL_AMFLAGS = -I scripts/autoconf
 
 # This ensures that pnglibconf.h gets built at the start of 'make all' or
 # 'make check', but it does not add dependencies to the individual programs,
@@ -715,43 +771,43 @@
 # result in the installed (system) pnglibconf.h being used and the result is
 # always wrong and always very confusing.
 BUILT_SOURCES = pnglibconf.h
-pngtest_SOURCES = pngtest.c
-pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-pngvalid_SOURCES = contrib/libtests/pngvalid.c
-pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-pngstest_SOURCES = contrib/libtests/pngstest.c
-pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-pngunknown_SOURCES = contrib/libtests/pngunknown.c
-pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-pngimage_SOURCES = contrib/libtests/pngimage.c
-pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-timepng_SOURCES = contrib/libtests/timepng.c
-timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-pngfix_SOURCES = contrib/tools/pngfix.c
-pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
-png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
-pngcp_SOURCES = contrib/tools/pngcp.c
-pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngtest_SOURCES = pngtest.c
+@ENABLE_TESTS_TRUE@pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngvalid_SOURCES = contrib/libtests/pngvalid.c
+@ENABLE_TESTS_TRUE@pngvalid_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngstest_SOURCES = contrib/libtests/pngstest.c
+@ENABLE_TESTS_TRUE@pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngunknown_SOURCES = contrib/libtests/pngunknown.c
+@ENABLE_TESTS_TRUE@pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngimage_SOURCES = contrib/libtests/pngimage.c
+@ENABLE_TESTS_TRUE@pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@timepng_SOURCES = contrib/libtests/timepng.c
+@ENABLE_TESTS_TRUE@timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TESTS_TRUE@pngcp_SOURCES = contrib/tools/pngcp.c
+@ENABLE_TESTS_TRUE@pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TOOLS_TRUE@pngfix_SOURCES = contrib/tools/pngfix.c
+@ENABLE_TOOLS_TRUE@pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+@ENABLE_TOOLS_TRUE@png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
 
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
-TESTS = \
-   tests/pngtest-all\
-   tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
-   tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
-   tests/pngvalid-gamma-expand16-background\
-   tests/pngvalid-gamma-expand16-transform tests/pngvalid-gamma-sbit\
-   tests/pngvalid-gamma-threshold tests/pngvalid-gamma-transform\
-   tests/pngvalid-progressive-size\
-   tests/pngvalid-progressive-interlace-standard\
-   tests/pngvalid-transform\
-   tests/pngvalid-progressive-standard tests/pngvalid-standard\
-   tests/pngstest-1.8 tests/pngstest-1.8-alpha tests/pngstest-linear\
-   tests/pngstest-linear-alpha tests/pngstest-none tests/pngstest-none-alpha\
-   tests/pngstest-sRGB tests/pngstest-sRGB-alpha tests/pngunknown-IDAT\
-   tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
-   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
-   tests/pngimage-quick tests/pngimage-full
+@ENABLE_TESTS_TRUE@TESTS = \
+@ENABLE_TESTS_TRUE@   tests/pngtest-all\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-gamma-expand16-background\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-gamma-expand16-transform tests/pngvalid-gamma-sbit\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-gamma-threshold tests/pngvalid-gamma-transform\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-progressive-size\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-progressive-interlace-standard\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-transform\
+@ENABLE_TESTS_TRUE@   tests/pngvalid-progressive-standard tests/pngvalid-standard\
+@ENABLE_TESTS_TRUE@   tests/pngstest-1.8 tests/pngstest-1.8-alpha tests/pngstest-linear\
+@ENABLE_TESTS_TRUE@   tests/pngstest-linear-alpha tests/pngstest-none tests/pngstest-none-alpha\
+@ENABLE_TESTS_TRUE@   tests/pngstest-sRGB tests/pngstest-sRGB-alpha tests/pngunknown-IDAT\
+@ENABLE_TESTS_TRUE@   tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
+@ENABLE_TESTS_TRUE@   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
+@ENABLE_TESTS_TRUE@   tests/pngimage-quick tests/pngimage-full
 
 
 # man pages
@@ -767,14 +823,24 @@
 	pngrutil.c pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c \
 	pngwutil.c png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h \
 	pngstruct.h pngusr.dfa $(am__append_2) $(am__append_3) \
-	$(am__append_4) $(am__append_5)
+	$(am__append_4) $(am__append_5) $(am__append_6) \
+	$(am__append_7)
+@PNG_LOONGARCH_LSX_TRUE@noinst_LTLIBRARIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+@PNG_LOONGARCH_LSX_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES = loongarch/loongarch_lsx_init.c\
+@PNG_LOONGARCH_LSX_TRUE@	loongarch/filter_lsx_intrinsics.c
+
+@PNG_LOONGARCH_LSX_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS = -mlsx
+@PNG_LOONGARCH_LSX_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
+# libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined \
 	-export-dynamic -version-number \
 	@PNGLIB_MAJOR@@PNGLIB_MINOR@:@PNGLIB_RELEASE@:0 \
-	$(am__append_6) $(am__append_7) $(am__append_8)
-@HAVE_LD_VERSION_SCRIPT_FALSE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
-@HAVE_LD_VERSION_SCRIPT_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.vers
+	$(am__append_8) $(am__append_9) $(am__append_10)
+@HAVE_LD_VERSION_SCRIPT_FALSE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES =  \
+@HAVE_LD_VERSION_SCRIPT_FALSE@	libpng.sym $(am__append_11)
+@HAVE_LD_VERSION_SCRIPT_TRUE@libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES =  \
+@HAVE_LD_VERSION_SCRIPT_TRUE@	libpng.vers $(am__append_11)
 pkginclude_HEADERS = png.h pngconf.h
 nodist_pkginclude_HEADERS = pnglibconf.h
 pkgconfig_DATA = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc
@@ -785,7 +851,7 @@
 EXTRA_DIST = \
 	ANNOUNCE AUTHORS CHANGES INSTALL LICENSE README TODO TRADEMARK \
 	pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
-	${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
+	${srcdir}/ci ${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
 	$(TESTS) $(XFAIL_TESTS) tests/pngstest \
 	CMakeLists.txt example.c libpng-manual.txt
 
@@ -808,7 +874,7 @@
 SYMBOL_CFLAGS = -DPNGLIB_LIBNAME='PNG@PNGLIB_MAJOR@@PNGLIB_MINOR@_0' \
 	-DPNGLIB_VERSION='@PNGLIB_VERSION@' \
 	-DSYMBOL_PREFIX='$(SYMBOL_PREFIX)' -DPNG_NO_USE_READ_MACROS \
-	-DPNG_BUILDING_SYMBOL_TABLE $(am__append_9)
+	-DPNG_BUILDING_SYMBOL_TABLE $(am__append_12)
 
 # EXT_LIST is a list of the possibly library directory extensions, this exists
 # because we can't find a good way of discovering the file extensions that are
@@ -965,6 +1031,17 @@
 	  echo rm -f $${locs}; \
 	  rm -f $${locs}; \
 	}
+
+clean-noinstLTLIBRARIES:
+	-test -z "$(noinst_LTLIBRARIES)" || rm -f $(noinst_LTLIBRARIES)
+	@list='$(noinst_LTLIBRARIES)'; \
+	locs=`for p in $$list; do echo $$p; done | \
+	      sed 's|^[^/]*$$|.|; s|/[^/]*$$||; s|$$|/so_locations|' | \
+	      sort -u`; \
+	test -z "$$locs" || { \
+	  echo rm -f $${locs}; \
+	  rm -f $${locs}; \
+	}
 arm/$(am__dirstamp):
 	@$(MKDIR_P) arm
 	@: > arm/$(am__dirstamp)
@@ -986,6 +1063,8 @@
 mips/mips_init.lo: mips/$(am__dirstamp) mips/$(DEPDIR)/$(am__dirstamp)
 mips/filter_msa_intrinsics.lo: mips/$(am__dirstamp) \
 	mips/$(DEPDIR)/$(am__dirstamp)
+mips/filter_mmi_inline_assembly.lo: mips/$(am__dirstamp) \
+	mips/$(DEPDIR)/$(am__dirstamp)
 intel/$(am__dirstamp):
 	@$(MKDIR_P) intel
 	@: > intel/$(am__dirstamp)
@@ -1009,6 +1088,19 @@
 
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la: $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES) $(EXTRA_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES) 
 	$(AM_V_CCLD)$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LINK) -rpath $(libdir) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_OBJECTS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD) $(LIBS)
+loongarch/$(am__dirstamp):
+	@$(MKDIR_P) loongarch
+	@: > loongarch/$(am__dirstamp)
+loongarch/$(DEPDIR)/$(am__dirstamp):
+	@$(MKDIR_P) loongarch/$(DEPDIR)
+	@: > loongarch/$(DEPDIR)/$(am__dirstamp)
+loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo:  \
+	loongarch/$(am__dirstamp) loongarch/$(DEPDIR)/$(am__dirstamp)
+loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo:  \
+	loongarch/$(am__dirstamp) loongarch/$(DEPDIR)/$(am__dirstamp)
+
+libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la: $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_OBJECTS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_DEPENDENCIES) $(EXTRA_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_DEPENDENCIES) 
+	$(AM_V_CCLD)$(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_LINK) $(am_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_rpath) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_OBJECTS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_LIBADD) $(LIBS)
 contrib/tools/$(am__dirstamp):
 	@$(MKDIR_P) contrib/tools
 	@: > contrib/tools/$(am__dirstamp)
@@ -1118,6 +1210,8 @@
 	-rm -f contrib/tools/*.$(OBJEXT)
 	-rm -f intel/*.$(OBJEXT)
 	-rm -f intel/*.lo
+	-rm -f loongarch/*.$(OBJEXT)
+	-rm -f loongarch/*.lo
 	-rm -f mips/*.$(OBJEXT)
 	-rm -f mips/*.lo
 	-rm -f powerpc/*.$(OBJEXT)
@@ -1156,6 +1250,9 @@
 @AMDEP_TRUE@@am__include@ @am__quote@contrib/tools/$(DEPDIR)/pngfix.Po@am__quote@ # am--include-marker
 @AMDEP_TRUE@@am__include@ @am__quote@intel/$(DEPDIR)/filter_sse2_intrinsics.Plo@am__quote@ # am--include-marker
 @AMDEP_TRUE@@am__include@ @am__quote@intel/$(DEPDIR)/intel_init.Plo@am__quote@ # am--include-marker
+@AMDEP_TRUE@@am__include@ @am__quote@loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Plo@am__quote@ # am--include-marker
+@AMDEP_TRUE@@am__include@ @am__quote@loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Plo@am__quote@ # am--include-marker
+@AMDEP_TRUE@@am__include@ @am__quote@mips/$(DEPDIR)/filter_mmi_inline_assembly.Plo@am__quote@ # am--include-marker
 @AMDEP_TRUE@@am__include@ @am__quote@mips/$(DEPDIR)/filter_msa_intrinsics.Plo@am__quote@ # am--include-marker
 @AMDEP_TRUE@@am__include@ @am__quote@mips/$(DEPDIR)/mips_init.Plo@am__quote@ # am--include-marker
 @AMDEP_TRUE@@am__include@ @am__quote@powerpc/$(DEPDIR)/filter_vsx_intrinsics.Plo@am__quote@ # am--include-marker
@@ -1215,6 +1312,20 @@
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LTCOMPILE) -c -o $@ $<
 
+loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo: loongarch/loongarch_lsx_init.c
+@am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS) $(CFLAGS) -MT loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo -MD -MP -MF loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Tpo -c -o loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo `test -f 'loongarch/loongarch_lsx_init.c' || echo '$(srcdir)/'`loongarch/loongarch_lsx_init.c
+@am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Tpo loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Plo
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	$(AM_V_CC)source='loongarch/loongarch_lsx_init.c' object='loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS) $(CFLAGS) -c -o loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.lo `test -f 'loongarch/loongarch_lsx_init.c' || echo '$(srcdir)/'`loongarch/loongarch_lsx_init.c
+
+loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo: loongarch/filter_lsx_intrinsics.c
+@am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS) $(CFLAGS) -MT loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo -MD -MP -MF loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Tpo -c -o loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo `test -f 'loongarch/filter_lsx_intrinsics.c' || echo '$(srcdir)/'`loongarch/filter_lsx_intrinsics.c
+@am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Tpo loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Plo
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	$(AM_V_CC)source='loongarch/filter_lsx_intrinsics.c' object='loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS) $(CFLAGS) -c -o loongarch/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.lo `test -f 'loongarch/filter_lsx_intrinsics.c' || echo '$(srcdir)/'`loongarch/filter_lsx_intrinsics.c
+
 mostlyclean-libtool:
 	-rm -f *.lo
 
@@ -1222,6 +1333,7 @@
 	-rm -rf .libs _libs
 	-rm -rf arm/.libs arm/_libs
 	-rm -rf intel/.libs intel/_libs
+	-rm -rf loongarch/.libs loongarch/_libs
 	-rm -rf mips/.libs mips/_libs
 	-rm -rf powerpc/.libs powerpc/_libs
 
@@ -1543,7 +1655,7 @@
 	  test x"$$VERBOSE" = x || cat $(TEST_SUITE_LOG);		\
 	fi;								\
 	echo "$${col}$$br$${std}"; 					\
-	echo "$${col}Testsuite summary for $(PACKAGE_STRING)$${std}";	\
+	echo "$${col}Testsuite summary"$(AM_TESTSUITE_SUMMARY_HEADER)"$${std}";	\
 	echo "$${col}$$br$${std}"; 					\
 	create_testsuite_report --maybe-color;				\
 	echo "$$col$$br$$std";						\
@@ -1815,7 +1927,6 @@
 @am__EXEEXT_TRUE@	--log-file $$b.log --trs-file $$b.trs \
 @am__EXEEXT_TRUE@	$(am__common_driver_flags) $(AM_TEST_LOG_DRIVER_FLAGS) $(TEST_LOG_DRIVER_FLAGS) -- $(TEST_LOG_COMPILE) \
 @am__EXEEXT_TRUE@	"$$tst" $(AM_TESTS_FD_REDIRECT)
-
 distdir: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) distdir-am
 
@@ -1876,6 +1987,10 @@
 	tardir=$(distdir) && $(am__tar) | XZ_OPT=$${XZ_OPT--e} xz -c >$(distdir).tar.xz
 	$(am__post_remove_distdir)
 
+dist-zstd: distdir
+	tardir=$(distdir) && $(am__tar) | zstd -c $${ZSTD_CLEVEL-$${ZSTD_OPT--19}} >$(distdir).tar.zst
+	$(am__post_remove_distdir)
+
 dist-tarZ: distdir
 	@echo WARNING: "Support for distribution archives compressed with" \
 		       "legacy program 'compress' is deprecated." >&2
@@ -1918,6 +2033,8 @@
 	  eval GZIP= gzip $(GZIP_ENV) -dc $(distdir).shar.gz | unshar ;;\
 	*.zip*) \
 	  unzip $(distdir).zip ;;\
+	*.tar.zst*) \
+	  zstd -dc $(distdir).tar.zst | $(am__untar) ;;\
 	esac
 	chmod -R a-w $(distdir)
 	chmod u+w $(distdir)
@@ -1933,7 +2050,7 @@
 	    $(DISTCHECK_CONFIGURE_FLAGS) \
 	    --srcdir=../.. --prefix="$$dc_install_base" \
 	  && $(MAKE) $(AM_MAKEFLAGS) \
-	  && $(MAKE) $(AM_MAKEFLAGS) dvi \
+	  && $(MAKE) $(AM_MAKEFLAGS) $(AM_DISTCHECK_DVI_TARGET) \
 	  && $(MAKE) $(AM_MAKEFLAGS) check \
 	  && $(MAKE) $(AM_MAKEFLAGS) install \
 	  && $(MAKE) $(AM_MAKEFLAGS) installcheck \
@@ -1993,13 +2110,16 @@
 		$(HEADERS) config.h
 install-binPROGRAMS: install-libLTLIBRARIES
 
+install-checkPROGRAMS: install-libLTLIBRARIES
+
 installdirs:
 	for dir in "$(DESTDIR)$(bindir)" "$(DESTDIR)$(libdir)" "$(DESTDIR)$(bindir)" "$(DESTDIR)$(man3dir)" "$(DESTDIR)$(man5dir)" "$(DESTDIR)$(pkgconfigdir)" "$(DESTDIR)$(pkgincludedir)" "$(DESTDIR)$(pkgincludedir)"; do \
 	  test -z "$$dir" || $(MKDIR_P) "$$dir"; \
 	done
 install: $(BUILT_SOURCES)
 	$(MAKE) $(AM_MAKEFLAGS) install-am
-install-exec: install-exec-am
+install-exec: $(BUILT_SOURCES)
+	$(MAKE) $(AM_MAKEFLAGS) install-exec-am
 install-data: install-data-am
 uninstall: uninstall-am
 
@@ -2036,6 +2156,8 @@
 	-rm -f contrib/tools/$(am__dirstamp)
 	-rm -f intel/$(DEPDIR)/$(am__dirstamp)
 	-rm -f intel/$(am__dirstamp)
+	-rm -f loongarch/$(DEPDIR)/$(am__dirstamp)
+	-rm -f loongarch/$(am__dirstamp)
 	-rm -f mips/$(DEPDIR)/$(am__dirstamp)
 	-rm -f mips/$(am__dirstamp)
 	-rm -f powerpc/$(DEPDIR)/$(am__dirstamp)
@@ -2052,7 +2174,8 @@
 clean: clean-am
 
 clean-am: clean-binPROGRAMS clean-checkPROGRAMS clean-generic \
-	clean-libLTLIBRARIES clean-libtool mostlyclean-am
+	clean-libLTLIBRARIES clean-libtool clean-noinstLTLIBRARIES \
+	mostlyclean-am
 
 distclean: distclean-am
 	-rm -f $(am__CONFIG_DISTCLEAN_FILES)
@@ -2086,6 +2209,9 @@
 	-rm -f contrib/tools/$(DEPDIR)/pngfix.Po
 	-rm -f intel/$(DEPDIR)/filter_sse2_intrinsics.Plo
 	-rm -f intel/$(DEPDIR)/intel_init.Plo
+	-rm -f loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Plo
+	-rm -f loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Plo
+	-rm -f mips/$(DEPDIR)/filter_mmi_inline_assembly.Plo
 	-rm -f mips/$(DEPDIR)/filter_msa_intrinsics.Plo
 	-rm -f mips/$(DEPDIR)/mips_init.Plo
 	-rm -f powerpc/$(DEPDIR)/filter_vsx_intrinsics.Plo
@@ -2171,6 +2297,9 @@
 	-rm -f contrib/tools/$(DEPDIR)/pngfix.Po
 	-rm -f intel/$(DEPDIR)/filter_sse2_intrinsics.Plo
 	-rm -f intel/$(DEPDIR)/intel_init.Plo
+	-rm -f loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-filter_lsx_intrinsics.Plo
+	-rm -f loongarch/$(DEPDIR)/libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la-loongarch_lsx_init.Plo
+	-rm -f mips/$(DEPDIR)/filter_mmi_inline_assembly.Plo
 	-rm -f mips/$(DEPDIR)/filter_msa_intrinsics.Plo
 	-rm -f mips/$(DEPDIR)/mips_init.Plo
 	-rm -f powerpc/$(DEPDIR)/filter_vsx_intrinsics.Plo
@@ -2200,21 +2329,22 @@
 uninstall-man: uninstall-man3 uninstall-man5
 
 .MAKE: all check check-am install install-am install-data-am \
-	install-exec-am install-strip uninstall-am
+	install-exec install-exec-am install-strip uninstall-am
 
 .PHONY: CTAGS GTAGS TAGS all all-am am--depfiles am--refresh check \
 	check-TESTS check-am clean clean-binPROGRAMS \
 	clean-checkPROGRAMS clean-cscope clean-generic \
-	clean-libLTLIBRARIES clean-libtool cscope cscopelist-am ctags \
-	ctags-am dist dist-all dist-bzip2 dist-gzip dist-hook \
-	dist-lzip dist-shar dist-tarZ dist-xz dist-zip distcheck \
-	distclean distclean-compile distclean-generic distclean-hdr \
-	distclean-libtool distclean-tags distcleancheck distdir \
-	distuninstallcheck dvi dvi-am html html-am info info-am \
-	install install-am install-binPROGRAMS install-binSCRIPTS \
-	install-data install-data-am install-data-hook install-dvi \
-	install-dvi-am install-exec install-exec-am install-exec-hook \
-	install-html install-html-am install-info install-info-am \
+	clean-libLTLIBRARIES clean-libtool clean-noinstLTLIBRARIES \
+	cscope cscopelist-am ctags ctags-am dist dist-all dist-bzip2 \
+	dist-gzip dist-hook dist-lzip dist-shar dist-tarZ dist-xz \
+	dist-zip dist-zstd distcheck distclean distclean-compile \
+	distclean-generic distclean-hdr distclean-libtool \
+	distclean-tags distcleancheck distdir distuninstallcheck dvi \
+	dvi-am html html-am info info-am install install-am \
+	install-binPROGRAMS install-binSCRIPTS install-data \
+	install-data-am install-data-hook install-dvi install-dvi-am \
+	install-exec install-exec-am install-exec-hook install-html \
+	install-html-am install-info install-info-am \
 	install-libLTLIBRARIES install-man install-man3 install-man5 \
 	install-nodist_pkgincludeHEADERS install-pdf install-pdf-am \
 	install-pkgconfigDATA install-pkgincludeHEADERS install-ps \
diff --git a/README b/README
index deabb5b..afb8c7a 100644
--- a/README
+++ b/README
@@ -1,57 +1,88 @@
-README for libpng version 1.6.38.git
+README for libpng version 1.6.43.git
 ====================================
 
-See the note about version numbers near the top of png.h.
-See INSTALL for instructions on how to install libpng.
+See the note about version numbers near the top of `png.h`.
+See `INSTALL` for instructions on how to install libpng.
 
-Libpng comes in several distribution formats.  Get libpng-*.tar.gz or
-libpng-*.tar.xz or if you want UNIX-style line endings in the text
-files, or lpng*.7z or lpng*.zip if you want DOS-style line endings.
+Libpng comes in several distribution formats.  Get `libpng-*.tar.gz`
+or `libpng-*.tar.xz` if you want UNIX-style line endings in the text
+files, or `lpng*.7z` or `lpng*.zip` if you want DOS-style line endings.
 
-Version 0.89 was the first official release of libpng.  Don't let the
-fact that it's the first release fool you.  The libpng library has been
-in extensive use and testing since mid-1995.  By late 1997 it had
-finally gotten to the stage where there hadn't been significant
-changes to the API in some time, and people have a bad feeling about
-libraries with versions < 1.0.  Version 1.0.0 was released in
-March 1998.
+For a detailed description on using libpng, read `libpng-manual.txt`.
+For examples of libpng in a program, see `example.c` and `pngtest.c`.
+For usage information and restrictions (what little they are) on libpng,
+see `png.h`.  For a description on using zlib (the compression library
+used by libpng) and zlib's restrictions, see `zlib.h`.
 
-****
-Note that some of the changes to the png_info structure render this
+You should use zlib 1.0.4 or later to run this, but it _may_ work with
+versions as old as zlib 0.95.  Even so, there are bugs in older zlib
+versions which can cause the output of invalid compression streams for
+some images.
+
+You should also note that zlib is a compression library that is useful
+for more things than just PNG files.  You can use zlib as a drop-in
+replacement for `fread()` and `fwrite()`, if you are so inclined.
+
+zlib should be available at the same place that libpng is, or at
+https://zlib.net .
+
+You may also want a copy of the PNG specification.  It is available
+as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
+these at http://www.libpng.org/pub/png/pngdocs.html .
+
+This code is currently being archived at https://libpng.sourceforge.io
+in the download area, and at http://libpng.download/src .
+
+This release, based in a large way on Glenn's, Guy's and Andreas'
+earlier work, was created and will be supported by myself and the PNG
+development group.
+
+Send comments, corrections and commendations to `png-mng-implement`
+at `lists.sourceforge.net`.  (Subscription is required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-implement
+to subscribe.)
+
+Send general questions about the PNG specification to `png-mng-misc`
+at `lists.sourceforge.net`.  (Subscription is required; visit
+https://lists.sourceforge.net/lists/listinfo/png-mng-misc
+to subscribe.)
+
+Historical notes
+----------------
+
+The libpng library has been in extensive use and testing since mid-1995.
+Version 0.89, published a year later, was the first official release.
+By late 1997, it had finally gotten to the stage where there hadn't
+been significant changes to the API in some time, and people have a bad
+feeling about libraries with versions below 1.0.  Version 1.0.0 was
+released in March 1998.
+
+Note that some of the changes to the `png_info` structure render this
 version of the library binary incompatible with libpng-0.89 or
 earlier versions if you are using a shared library.  The type of the
-"filler" parameter for png_set_filler() has changed from png_byte to
-png_uint_32, which will affect shared-library applications that use
-this function.
+`filler` parameter for `png_set_filler()` has changed from `png_byte`
+to `png_uint_32`, which will affect shared-library applications that
+use this function.
 
-To avoid problems with changes to the internals of the png info_struct,
+To avoid problems with changes to the internals of the `info_struct`,
 new APIs have been made available in 0.95 to avoid direct application
-access to info_ptr.  These functions are the png_set_<chunk> and
-png_get_<chunk> functions.  These functions should be used when
-accessing/storing the info_struct data, rather than manipulating it
+access to `info_ptr`.  These functions are the `png_set_<chunk>` and
+`png_get_<chunk>` functions.  These functions should be used when
+accessing/storing the `info_struct` data, rather than manipulating it
 directly, to avoid such problems in the future.
 
 It is important to note that the APIs did not make current programs
 that access the info struct directly incompatible with the new
 library, through libpng-1.2.x.  In libpng-1.4.x, which was meant to
-be a transitional release, members of the png_struct and the
-info_struct can still be accessed, but the compiler will issue a
+be a transitional release, members of the `png_struct` and the
+`info_struct` can still be accessed, but the compiler will issue a
 warning about deprecated usage.  Since libpng-1.5.0, direct access
 to these structs is not allowed, and the definitions of the structs
-reside in private pngstruct.h and pnginfo.h header files that are not
-accessible to applications.  It is strongly suggested that new
-programs use the new APIs (as shown in example.c and pngtest.c), and
-older programs be converted to the new format, to facilitate upgrades
-in the future.
-****
-
-Additions since 0.90 include the ability to compile libpng as a
-Windows DLL, and new APIs for accessing data in the info struct.
-Experimental functions include the ability to set weighting and cost
-factors for row filter selection, direct reads of integers from buffers
-on big-endian processors that support misaligned data access, faster
-methods of doing alpha composition, and more accurate 16->8 bit color
-conversion.
+reside in private `pngstruct.h` and `pnginfo.h` header files that are
+not accessible to applications.  It is strongly suggested that new
+programs use the new APIs (as shown in `example.c` and `pngtest.c`),
+and older programs be converted to the new format, to facilitate
+upgrades in the future.
 
 The additions since 0.89 include the ability to read from a PNG stream
 which has had some (or all) of the signature bytes read by the calling
@@ -61,118 +92,86 @@
 to set different actions based on whether the CRC error occurred in a
 critical or an ancillary chunk.
 
-For a detailed description on using libpng, read libpng-manual.txt.
-For examples of libpng in a program, see example.c and pngtest.c.  For
-usage information and restrictions (what little they are) on libpng,
-see png.h.  For a description on using zlib (the compression library
-used by libpng) and zlib's restrictions, see zlib.h
+The additions since 0.90 include the ability to compile libpng as a
+Windows DLL, and new APIs for accessing data in the `info_struct`.
+Experimental functions included the ability to set weighting and cost
+factors for row filter selection, direct reads of integers from buffers
+on big-endian processors that support misaligned data access, faster
+methods of doing alpha composition, and more accurate 16-to-8 bit color
+conversion.  Some of these experimental functions, such as the weighted
+filter heuristics, have since been removed.
 
-I have included a general makefile, as well as several machine and
-compiler specific ones, but you may have to modify one for your own
-needs.
+Files included in this distribution
+-----------------------------------
 
-You should use zlib 1.0.4 or later to run this, but it MAY work with
-versions as old as zlib 0.95.  Even so, there are bugs in older zlib
-versions which can cause the output of invalid compression streams for
-some images.
-
-You should also note that zlib is a compression library that is useful
-for more things than just PNG files.  You can use zlib as a drop-in
-replacement for fread() and fwrite(), if you are so inclined.
-
-zlib should be available at the same place that libpng is, or at
-https://zlib.net.
-
-You may also want a copy of the PNG specification.  It is available
-as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
-these at http://www.libpng.org/pub/png/pngdocs.html .
-
-This code is currently being archived at libpng.sourceforge.io in the
-[DOWNLOAD] area, and at http://libpng.download/src .
-
-This release, based in a large way on Glenn's, Guy's and Andreas'
-earlier work, was created and will be supported by myself and the PNG
-development group.
-
-Send comments/corrections/commendations to png-mng-implement at
-lists.sourceforge.net (subscription required; visit
-https://lists.sourceforge.net/lists/listinfo/png-mng-implement
-to subscribe).
-
-Send general questions about the PNG specification to png-mng-misc
-at lists.sourceforge.net (subscription required; visit
-https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
-subscribe).
-
-Files in this distribution:
-
-      ANNOUNCE      =>  Announcement of this version, with recent changes
-      AUTHORS       =>  List of contributing authors
-      CHANGES       =>  Description of changes between libpng versions
-      KNOWNBUG      =>  List of known bugs and deficiencies
-      LICENSE       =>  License to use and redistribute libpng
-      README        =>  This file
-      TODO          =>  Things not implemented in the current library
-      TRADEMARK     =>  Trademark information
-      example.c     =>  Example code for using libpng functions
-      libpng.3      =>  manual page for libpng (includes libpng-manual.txt)
-      libpng-manual.txt  =>  Description of libpng and its functions
-      libpngpf.3    =>  manual page for libpng's private functions
-      png.5         =>  manual page for the PNG format
-      png.c         =>  Basic interface functions common to library
-      png.h         =>  Library function and interface declarations (public)
-      pngpriv.h     =>  Library function and interface declarations (private)
-      pngconf.h     =>  System specific library configuration (public)
-      pngstruct.h   =>  png_struct declaration (private)
-      pnginfo.h     =>  png_info struct declaration (private)
-      pngdebug.h    =>  debugging macros (private)
-      pngerror.c    =>  Error/warning message I/O functions
-      pngget.c      =>  Functions for retrieving info from struct
-      pngmem.c      =>  Memory handling functions
-      pngbar.png    =>  PNG logo, 88x31
-      pngnow.png    =>  PNG logo, 98x31
-      pngpread.c    =>  Progressive reading functions
-      pngread.c     =>  Read data/helper high-level functions
-      pngrio.c      =>  Lowest-level data read I/O functions
-      pngrtran.c    =>  Read data transformation functions
-      pngrutil.c    =>  Read data utility functions
-      pngset.c      =>  Functions for storing data into the info_struct
-      pngtest.c     =>  Library test program
-      pngtest.png   =>  Library test sample image
-      pngtrans.c    =>  Common data transformation functions
-      pngwio.c      =>  Lowest-level write I/O functions
-      pngwrite.c    =>  High-level write functions
-      pngwtran.c    =>  Write data transformations
-      pngwutil.c    =>  Write utility functions
-      arm           =>  Contains optimized code for the ARM platform
-      powerpc       =>  Contains optimized code for the PowerPC platform
-      contrib       =>  Contributions
-       arm-neon         =>  Optimized code for ARM-NEON platform
-       powerpc-vsx      =>  Optimized code for POWERPC-VSX platform
-       examples         =>  Example programs
-       gregbook         =>  source code for PNG reading and writing, from
-                            Greg Roelofs' "PNG: The Definitive Guide",
-                            O'Reilly, 1999
-       libtests         =>  Test programs
-       mips-msa         =>  Optimized code for MIPS-MSA platform
-       pngminim         =>  Minimal decoder, encoder, and progressive decoder
-                            programs demonstrating use of pngusr.dfa
-       pngminus         =>  Simple pnm2png and png2pnm programs
-       pngsuite         =>  Test images
-       testpngs
-       tools            =>  Various tools
-       visupng          =>  Contains a MSVC workspace for VisualPng
-      intel             =>  Optimized code for INTEL-SSE2 platform
-      mips              =>  Optimized code for MIPS platform
-      projects      =>  Contains project files and workspaces for
-                        building a DLL
-       owatcom          =>  Contains a WATCOM project for building libpng
-       visualc71        =>  Contains a Microsoft Visual C++ (MSVC)
-                            workspace for building libpng and zlib
-       vstudio          =>  Contains a Microsoft Visual C++ (MSVC)
-                            workspace for building libpng and zlib
-      scripts       =>  Directory containing scripts for building libpng:
-                            (see scripts/README.txt for the list of scripts)
+    ANNOUNCE      =>  Announcement of this version, with recent changes
+    AUTHORS       =>  List of contributing authors
+    CHANGES       =>  Description of changes between libpng versions
+    INSTALL       =>  Instructions to install libpng
+    LICENSE       =>  License to use and redistribute libpng
+    README        =>  This file
+    TODO          =>  Things not implemented in the current library
+    TRADEMARK     =>  Trademark information
+    example.c     =>  Example code for using libpng functions
+    libpng.3      =>  Manual page for libpng (includes libpng-manual.txt)
+    libpng-manual.txt  =>  Description of libpng and its functions
+    libpngpf.3    =>  Manual page for libpng's private functions (deprecated)
+    png.5         =>  Manual page for the PNG format
+    png.c         =>  Basic interface functions common to library
+    png.h         =>  Library function and interface declarations (public)
+    pngpriv.h     =>  Library function and interface declarations (private)
+    pngconf.h     =>  System specific library configuration (public)
+    pngstruct.h   =>  png_struct declaration (private)
+    pnginfo.h     =>  png_info struct declaration (private)
+    pngdebug.h    =>  debugging macros (private)
+    pngerror.c    =>  Error/warning message I/O functions
+    pngget.c      =>  Functions for retrieving info from struct
+    pngmem.c      =>  Memory handling functions
+    pngbar.png    =>  PNG logo, 88x31
+    pngnow.png    =>  PNG logo, 98x31
+    pngpread.c    =>  Progressive reading functions
+    pngread.c     =>  Read data/helper high-level functions
+    pngrio.c      =>  Lowest-level data read I/O functions
+    pngrtran.c    =>  Read data transformation functions
+    pngrutil.c    =>  Read data utility functions
+    pngset.c      =>  Functions for storing data into the info_struct
+    pngtest.c     =>  Library test program
+    pngtest.png   =>  Library test sample image
+    pngtrans.c    =>  Common data transformation functions
+    pngwio.c      =>  Lowest-level write I/O functions
+    pngwrite.c    =>  High-level write functions
+    pngwtran.c    =>  Write data transformations
+    pngwutil.c    =>  Write utility functions
+    arm/          =>  Optimized code for the ARM platform
+    intel/        =>  Optimized code for the INTEL-SSE2 platform
+    mips/         =>  Optimized code for the MIPS platform
+    powerpc/      =>  Optimized code for the PowerPC platform
+    ci/           =>  Scripts for continuous integration
+    contrib/      =>  External contributions
+        arm-neon/     =>  Optimized code for the ARM-NEON platform
+        mips-msa/     =>  Optimized code for the MIPS-MSA platform
+        powerpc-vsx/  =>  Optimized code for the POWERPC-VSX platform
+        examples/     =>  Examples of libpng usage
+        gregbook/     =>  Source code for PNG reading and writing, from
+                          "PNG: The Definitive Guide" by Greg Roelofs,
+                          O'Reilly, 1999
+        libtests/     =>  Test programs
+        oss-fuzz/     =>  Files used by the OSS-Fuzz project for fuzz-testing
+                          libpng
+        pngminim/     =>  Minimal decoder, encoder, and progressive decoder
+                          programs demonstrating the use of pngusr.dfa
+        pngminus/     =>  Simple pnm2png and png2pnm programs
+        pngsuite/     =>  Test images
+        testpngs/     =>  Test images
+        tools/        =>  Various tools
+        visupng/      =>  VisualPng, a Windows viewer for PNG images
+    projects/     =>  Project files and workspaces for various IDEs
+        owatcom/      =>  OpenWatcom project
+        visualc71/    =>  Microsoft Visual C++ 7.1 workspace
+        vstudio/      =>  Microsoft Visual Studio workspace
+    scripts/      =>  Scripts and makefiles for building libpng
+                      (see scripts/README.txt for the complete list)
+    tests/        =>  Test scripts
 
 Good luck, and happy coding!
 
diff --git a/aclocal.m4 b/aclocal.m4
index bc18c34..2085004 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.16.1 -*- Autoconf -*-
+# generated automatically by aclocal 1.16.5 -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -14,13 +14,13 @@
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
-m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.69],,
-[m4_warning([this file was generated for autoconf 2.69.
+m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.72],,
+[m4_warning([this file was generated for autoconf 2.72.
 You have another version of autoconf.  It may work, but is not guaranteed to.
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
 
-# Copyright (C) 2002-2018 Free Software Foundation, Inc.
+# Copyright (C) 2002-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -35,7 +35,7 @@
 [am__api_version='1.16'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.16.1], [],
+m4_if([$1], [1.16.5], [],
       [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
 
@@ -51,14 +51,14 @@
 # Call AM_AUTOMAKE_VERSION and AM_AUTOMAKE_VERSION so they can be traced.
 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.16.1])dnl
+[AM_AUTOMAKE_VERSION([1.16.5])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 
 # Figure out how to run the assembler.                      -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -78,7 +78,7 @@
 
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -130,7 +130,7 @@
 
 # AM_CONDITIONAL                                            -*- Autoconf -*-
 
-# Copyright (C) 1997-2018 Free Software Foundation, Inc.
+# Copyright (C) 1997-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -161,7 +161,7 @@
 Usually this means the macro was only invoked conditionally.]])
 fi])])
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -352,7 +352,7 @@
 
 # Generate code to set up dependency tracking.              -*- Autoconf -*-
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -391,7 +391,9 @@
   done
   if test $am_rc -ne 0; then
     AC_MSG_FAILURE([Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  Try re-running configure with the
+    for automatic dependency tracking.  If GNU make was not used, consider
+    re-running the configure script with MAKE="gmake" (or whatever is
+    necessary).  You can also try re-running configure with the
     '--disable-dependency-tracking' option to at least be able to build
     the package (albeit without support for automatic dependency tracking).])
   fi
@@ -418,7 +420,7 @@
 
 # Do all the work for Automake.                             -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -446,6 +448,10 @@
 # release and drop the old call support.
 AC_DEFUN([AM_INIT_AUTOMAKE],
 [AC_PREREQ([2.65])dnl
+m4_ifdef([_$0_ALREADY_INIT],
+  [m4_fatal([$0 expanded multiple times
+]m4_defn([_$0_ALREADY_INIT]))],
+  [m4_define([_$0_ALREADY_INIT], m4_expansion_stack)])dnl
 dnl Autoconf wants to disallow AM_ names.  We explicitly allow
 dnl the ones we care about.
 m4_pattern_allow([^AM_[A-Z]+FLAGS$])dnl
@@ -482,7 +488,7 @@
 [_AM_SET_OPTIONS([$1])dnl
 dnl Diagnose old-style AC_INIT with new-style AM_AUTOMAKE_INIT.
 m4_if(
-  m4_ifdef([AC_PACKAGE_NAME], [ok]):m4_ifdef([AC_PACKAGE_VERSION], [ok]),
+  m4_ifset([AC_PACKAGE_NAME], [ok]):m4_ifset([AC_PACKAGE_VERSION], [ok]),
   [ok:ok],,
   [m4_fatal([AC_INIT should be called with package and version arguments])])dnl
  AC_SUBST([PACKAGE], ['AC_PACKAGE_TARNAME'])dnl
@@ -534,6 +540,20 @@
 		  [m4_define([AC_PROG_OBJCXX],
 			     m4_defn([AC_PROG_OBJCXX])[_AM_DEPENDENCIES([OBJCXX])])])dnl
 ])
+# Variables for tags utilities; see am/tags.am
+if test -z "$CTAGS"; then
+  CTAGS=ctags
+fi
+AC_SUBST([CTAGS])
+if test -z "$ETAGS"; then
+  ETAGS=etags
+fi
+AC_SUBST([ETAGS])
+if test -z "$CSCOPE"; then
+  CSCOPE=cscope
+fi
+AC_SUBST([CSCOPE])
+
 AC_REQUIRE([AM_SILENT_RULES])dnl
 dnl The testsuite driver may need to know about EXEEXT, so add the
 dnl 'am__EXEEXT' conditional if _AM_COMPILER_EXEEXT was seen.  This
@@ -615,7 +635,7 @@
 done
 echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_count])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -636,7 +656,7 @@
 fi
 AC_SUBST([install_sh])])
 
-# Copyright (C) 2003-2018 Free Software Foundation, Inc.
+# Copyright (C) 2003-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -658,7 +678,7 @@
 # Add --enable-maintainer-mode option to configure.         -*- Autoconf -*-
 # From Jim Meyering
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -693,7 +713,7 @@
 
 # Check to see how 'make' treats includes.	            -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -736,7 +756,7 @@
 
 # Fake the existence of programs that GNU maintainers use.  -*- Autoconf -*-
 
-# Copyright (C) 1997-2018 Free Software Foundation, Inc.
+# Copyright (C) 1997-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -757,12 +777,7 @@
 [AC_REQUIRE([AM_AUX_DIR_EXPAND])dnl
 AC_REQUIRE_AUX_FILE([missing])dnl
 if test x"${MISSING+set}" != xset; then
-  case $am_aux_dir in
-  *\ * | *\	*)
-    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
-  *)
-    MISSING="\${SHELL} $am_aux_dir/missing" ;;
-  esac
+  MISSING="\${SHELL} '$am_aux_dir/missing'"
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
@@ -775,7 +790,7 @@
 
 # Helper functions for option handling.                     -*- Autoconf -*-
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -804,7 +819,7 @@
 AC_DEFUN([_AM_IF_OPTION],
 [m4_ifset(_AM_MANGLE_OPTION([$1]), [$2], [$3])])
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -851,7 +866,7 @@
 # For backward compatibility.
 AC_DEFUN_ONCE([AM_PROG_CC_C_O], [AC_REQUIRE([AC_PROG_CC])])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -870,7 +885,7 @@
 
 # Check to make sure that the build environment is sane.    -*- Autoconf -*-
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -951,7 +966,7 @@
 rm -f conftest.file
 ])
 
-# Copyright (C) 2009-2018 Free Software Foundation, Inc.
+# Copyright (C) 2009-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1011,7 +1026,7 @@
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 ])
 
-# Copyright (C) 2001-2018 Free Software Foundation, Inc.
+# Copyright (C) 2001-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1039,7 +1054,7 @@
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 AC_SUBST([INSTALL_STRIP_PROGRAM])])
 
-# Copyright (C) 2006-2018 Free Software Foundation, Inc.
+# Copyright (C) 2006-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1058,7 +1073,7 @@
 
 # Check how to create a tarball.                            -*- Autoconf -*-
 
-# Copyright (C) 2004-2018 Free Software Foundation, Inc.
+# Copyright (C) 2004-2021 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1189,8 +1204,8 @@
 AC_SUBST([am__untar])
 ]) # _AM_PROG_TAR
 
-m4_include([scripts/libtool.m4])
-m4_include([scripts/ltoptions.m4])
-m4_include([scripts/ltsugar.m4])
-m4_include([scripts/ltversion.m4])
-m4_include([scripts/lt~obsolete.m4])
+m4_include([scripts/autoconf/libtool.m4])
+m4_include([scripts/autoconf/ltoptions.m4])
+m4_include([scripts/autoconf/ltsugar.m4])
+m4_include([scripts/autoconf/ltversion.m4])
+m4_include([scripts/autoconf/lt~obsolete.m4])
diff --git a/arm/arm_init.c b/arm/arm_init.c
index a34ecdb..84d0555 100644
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@@ -1,7 +1,7 @@
 
 /* arm_init.c - NEON optimised filter functions
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 2014,2016 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
  *
@@ -10,9 +10,7 @@
  * and license in png.h
  */
 
-/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
- * called.
- */
+/* This module requires POSIX 1003.1 functions. */
 #define _POSIX_SOURCE 1
 
 #include "../pngpriv.h"
@@ -33,21 +31,26 @@
  * has partial support is contrib/arm-neon/linux.c - a generic Linux
  * implementation which reads /proc/cpufino.
  */
+#include <signal.h> /* for sig_atomic_t */
+
 #ifndef PNG_ARM_NEON_FILE
-#  ifdef __linux__
-#     define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+#  if defined(__aarch64__) || defined(_M_ARM64)
+     /* ARM Neon is expected to be unconditionally available on ARM64. */
+#    error "PNG_ARM_NEON_CHECK_SUPPORTED must not be defined on ARM64"
+#  elif defined(__ARM_NEON__) || defined(__ARM_NEON)
+     /* ARM Neon is expected to be available on the target CPU architecture. */
+#    error "PNG_ARM_NEON_CHECK_SUPPORTED must not be defined on this CPU arch"
+#  elif defined(__linux__)
+#    define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+#  else
+#    error "No support for run-time ARM Neon checking; use compile-time options"
 #  endif
 #endif
 
-#ifdef PNG_ARM_NEON_FILE
-
-#include <signal.h> /* for sig_atomic_t */
 static int png_have_neon(png_structp png_ptr);
-#include PNG_ARM_NEON_FILE
-
-#else  /* PNG_ARM_NEON_FILE */
-#  error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
-#endif /* PNG_ARM_NEON_FILE */
+#ifdef PNG_ARM_NEON_FILE
+#  include PNG_ARM_NEON_FILE
+#endif
 #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
 
 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
diff --git a/arm/palette_neon_intrinsics.c b/arm/palette_neon_intrinsics.c
index 49909d4..92c7d6f 100644
--- a/arm/palette_neon_intrinsics.c
+++ b/arm/palette_neon_intrinsics.c
@@ -65,11 +65,12 @@
    png_uint_32 row_width = row_info->width;
    const png_uint_32 *riffled_palette =
       (const png_uint_32 *)png_ptr->riffled_palette;
-   const png_int_32 pixels_per_chunk = 4;
-   int i;
+   const png_uint_32 pixels_per_chunk = 4;
+   png_uint_32 i;
 
    png_debug(1, "in png_do_expand_palette_rgba8_neon");
 
+   PNG_UNUSED(row)
    if (row_width < pixels_per_chunk)
       return 0;
 
@@ -109,10 +110,11 @@
    png_uint_32 row_width = row_info->width;
    png_const_bytep palette = (png_const_bytep)png_ptr->palette;
    const png_uint_32 pixels_per_chunk = 8;
-   int i;
+   png_uint_32 i;
 
    png_debug(1, "in png_do_expand_palette_rgb8_neon");
 
+   PNG_UNUSED(row)
    if (row_width <= pixels_per_chunk)
       return 0;
 
diff --git a/autogen.sh b/autogen.sh
index a46daf6..4ac8f4b 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -77,13 +77,14 @@
    config.sub configure depcomp install-sh ltmain.sh missing\
    test-driver"
 #
-# Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
+# Files generated by versions of autoconf >2.68 or automake >1.13 (i.e. later
 # versions than those required by configure.ac):
 libpng_autotools_extra="compile config.h.in~"
 #
 # These are separate because 'maintainer-clean' does not remove them.
-libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
-   scripts/ltsugar.m4 scripts/ltversion.m4 scripts/lt~obsolete.m4"
+libpng_libtool_files="scripts/autoconf/libtool.m4 scripts/autoconf/ltoptions.m4\
+   scripts/autoconf/ltsugar.m4 scripts/autoconf/ltversion.m4\
+   scripts/autoconf/lt~obsolete.m4"
 
 libpng_autotools_dirs="autom4te.cache" # not required
 #
diff --git a/ci/.shellcheckrc b/ci/.shellcheckrc
new file mode 100644
index 0000000..3c035d6
--- /dev/null
+++ b/ci/.shellcheckrc
@@ -0,0 +1,11 @@
+# Disable the "expressions don't expand in single quotes, use double quotes"
+# advice. We need the regular expressions to remain uninterpolated.
+disable=SC2016
+
+# Disable the "variable appears unused" warning caused by the use of getopts
+# with an obligatory (but unused) variable name in the main function.
+disable=SC2034
+
+# Disable all the "quote to prevent globbing or word splitting" advice.
+# We need word splitting for well-known variables like MAKEFLAGS and CFLAGS.
+disable=SC2086,SC2206
diff --git a/ci/LICENSE_MIT.txt b/ci/LICENSE_MIT.txt
new file mode 100644
index 0000000..9cf1062
--- /dev/null
+++ b/ci/LICENSE_MIT.txt
@@ -0,0 +1,19 @@
+MIT License
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/ci/ci_lint.sh b/ci/ci_lint.sh
new file mode 100755
index 0000000..9b9dc6b
--- /dev/null
+++ b/ci/ci_lint.sh
@@ -0,0 +1,135 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+# Initialize the global constants CI_{...}{CHECK,CHECKER,LINT}.
+CI_SHELLCHECK="${CI_SHELLCHECK:-shellcheck}"
+CI_EDITORCONFIG_CHECKER="${CI_EDITORCONFIG_CHECKER:-editorconfig-checker}"
+CI_YAMLLINT="${CI_YAMLLINT:-yamllint}"
+
+# Initialize the global lint counter.
+CI_LINT_COUNTER=0
+
+function ci_init_lint {
+    ci_info "## START OF LINTING ##"
+    local my_program
+    # Complete the initialization of CI_SHELLCHECK.
+    # Set it to the empty string if the shellcheck program is unavailable.
+    my_program="$(command -v "$CI_SHELLCHECK")" || {
+        ci_warn "program not found: '$CI_SHELLCHECK'"
+    }
+    CI_SHELLCHECK="$my_program"
+    # Complete the initialization of CI_EDITORCONFIG_CHECKER.
+    # Set it to the empty string if the editorconfig-checker program is unavailable.
+    my_program="$(command -v "$CI_EDITORCONFIG_CHECKER")" || {
+        ci_warn "program not found: '$CI_EDITORCONFIG_CHECKER'"
+    }
+    CI_EDITORCONFIG_CHECKER="$my_program"
+    # Complete the initialization of CI_YAMLLINT.
+    # Set it to the empty string if the yamllint program is unavailable.
+    my_program="$(command -v "$CI_YAMLLINT")" || {
+        ci_warn "program not found: '$CI_YAMLLINT'"
+    }
+    CI_YAMLLINT="$my_program"
+}
+
+function ci_finish_lint {
+    ci_info "## END OF LINTING ##"
+    if [[ $CI_LINT_COUNTER -eq 0 ]]
+    then
+        ci_info "success!"
+        return 0
+    else
+        ci_warn "$CI_LINT_COUNTER failure(s)"
+        return 1
+    fi
+}
+
+function ci_lint_ci_scripts {
+    [[ -x $CI_SHELLCHECK ]] || {
+        ci_warn "## NOT LINTING: CI scripts ##"
+        return 0
+    }
+    ci_info "## LINTING: CI scripts ##"
+    local my_file
+    ci_spawn "$CI_SHELLCHECK" --version
+    for my_file in ci/*.sh
+    do
+        ci_spawn "$CI_SHELLCHECK" -x "$my_file" || {
+            CI_LINT_COUNTER=$((CI_LINT_COUNTER + 1))
+        }
+    done
+}
+
+function ci_lint_text_files {
+    [[ -x $CI_EDITORCONFIG_CHECKER ]] || {
+        ci_warn "## NOT LINTING: text files ##"
+        return 0
+    }
+    ci_info "## LINTING: text files ##"
+    local my_file
+    ci_spawn "$CI_EDITORCONFIG_CHECKER" --version
+    ci_spawn "$CI_EDITORCONFIG_CHECKER" || {
+        CI_LINT_COUNTER=$((CI_LINT_COUNTER + 1))
+    }
+}
+
+function ci_lint_yaml_files {
+    [[ -x $CI_YAMLLINT ]] || {
+        ci_warn "## NOT LINTING: YAML files ##"
+        return 0
+    }
+    ci_info "## LINTING: YAML files ##"
+    local my_file
+    ci_spawn "$CI_YAMLLINT" --version
+    for my_file in .*.yml
+    do
+        ci_spawn "$CI_YAMLLINT" --strict "$my_file" || {
+            CI_LINT_COUNTER=$((CI_LINT_COUNTER + 1))
+        }
+    done
+}
+
+function ci_lint {
+    ci_init_lint
+    ci_lint_ci_scripts
+    ci_lint_text_files
+    ci_lint_yaml_files
+    # TODO: ci_lint_png_files, etc.
+    ci_finish_lint
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>]"
+    echo "options: -?|-h|--help"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    [[ $# -eq 0 ]] || {
+        echo >&2 "error: unexpected argument: '$1'"
+        usage 2
+    }
+    # And... go!
+    ci_lint
+}
+
+main "$@"
diff --git a/ci/ci_shellify.sh b/ci/ci_shellify.sh
new file mode 100755
index 0000000..bf6dd7c
--- /dev/null
+++ b/ci/ci_shellify.sh
@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+function ci_shellify_c {
+    # Convert C preprocessor text, specifically originating
+    # from png.h, to shell scripting text.
+    # Select only the easy-to-parse definitions of PNG_LIBPNG_*.
+    sed -n -e '/^\# *define * PNG_LIBPNG_[^ ]* * ["0-9A-Za-z_]/ p' |
+        sed -e 's/^\# *define * PNG\([^ ]*\) * \([^ ]*\)/PNG\1=\2/' \
+            -e 's/=PNG\([0-9A-Za-z_]*\)/=\${PNG\1}/' \
+            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
+}
+
+function ci_shellify_autoconf {
+    # Convert autoconf (M4) text, specifically originating
+    # from configure.ac, to shell scripting text.
+    # Select only the easy-to-parse definitions of PNGLIB_*.
+    sed -n -e '/^ *PNGLIB_[^ ]*=[$"0-9A-Za-z_]/ p' |
+        sed -e 's/^ *PNG\([0-9A-Za-z_]*\)=\([^# ]*\).*$/PNG\1=\2/' \
+            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
+}
+
+function ci_shellify_cmake {
+    # Convert CMake lists text, specifically originating
+    # from CMakeLists.txt, to shell scripting text.
+    # Select only the easy-to-parse definitions of PNGLIB_*.
+    sed -n -e '/^ *set *(PNGLIB_[^ ]* * [$"0-9A-Za-z_].*)/ p' |
+        sed -e 's/^ *set *(PNG\([^ ]*\) * \([^() ]*\)).*$/PNG\1=\2/' \
+            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
+}
+
+function ci_shellify {
+    local arg filename
+    for arg in "$@"
+    do
+        test -f "$arg" || ci_err "no such file: '$arg'"
+        filename="$(basename -- "$arg")"
+        case "$filename" in
+        ( *.[ch] )
+            [[ $filename == png.h ]] || {
+                ci_err "unable to shellify: '$filename' (expecting: 'png.h')"
+            }
+            ci_shellify_c <"$arg" ;;
+        ( config* | *.ac )
+            [[ $filename == configure.ac ]] || {
+                ci_err "unable to shellify: '$filename' (expecting: 'configure.ac')"
+            }
+            ci_shellify_autoconf <"$arg" ;;
+        ( *CMake* | *cmake* | *.txt )
+            [[ $filename == [Cc][Mm]ake[Ll]ists.txt ]] || {
+                ci_err "unable to shellify: '$filename' (expecting: 'CMakeLists.txt')"
+            }
+            ci_shellify_cmake <"$arg" ;;
+        ( * )
+            ci_err "unable to shellify: '$arg'" ;;
+        esac
+    done
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>] <files>..."
+    echo "options: -?|-h|--help"
+    echo "files: png.h|configure.ac|CMakeLists.txt"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    [[ $# -eq 0 ]] && usage 2
+    # And... go!
+    ci_shellify "$@"
+}
+
+main "$@"
diff --git a/ci/ci_verify_cmake.sh b/ci/ci_verify_cmake.sh
new file mode 100755
index 0000000..0985d5f
--- /dev/null
+++ b/ci/ci_verify_cmake.sh
@@ -0,0 +1,218 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+CI_SRC_DIR="$CI_TOPLEVEL_DIR"
+CI_OUT_DIR="$CI_TOPLEVEL_DIR/out"
+CI_BUILD_DIR="$CI_OUT_DIR/ci_verify_cmake.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.build"
+CI_INSTALL_DIR="$CI_OUT_DIR/ci_verify_cmake.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.install"
+
+# Keep the following relative paths in sync with the absolute paths.
+# We use them for the benefit of native Windows tools that might be
+# otherwise confused by the path encoding used by Bash-on-Windows.
+CI_BUILD_TO_SRC_RELDIR="../.."
+CI_BUILD_TO_INSTALL_RELDIR="../ci_verify_cmake.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.install"
+
+function ci_init_build {
+    # Ensure that the mandatory variables are initialized.
+    CI_CMAKE="${CI_CMAKE:-cmake}"
+    CI_CTEST="${CI_CTEST:-ctest}"
+    CI_CMAKE_BUILD_TYPE="${CI_CMAKE_BUILD_TYPE:-Release}"
+    if [[ $CI_CMAKE_GENERATOR == "Visual Studio"* ]]
+    then
+        # Clean up incidental mixtures of Windows and Bash-on-Windows
+        # environment variables, to avoid confusing MSBuild.
+        [[ $TEMP && ( $Temp || $temp ) ]] && unset TEMP
+        [[ $TMP && ( $Tmp || $tmp ) ]] && unset TMP
+        # Ensure that CI_CMAKE_GENERATOR_PLATFORM is initialized for this generator.
+        [[ $CI_CMAKE_GENERATOR_PLATFORM ]] || {
+            ci_err_internal "missing \$CI_CMAKE_GENERATOR_PLATFORM"
+        }
+    elif [[ -x $(command -v ninja) ]]
+    then
+        CI_CMAKE_GENERATOR="${CI_CMAKE_GENERATOR:-Ninja}"
+    fi
+}
+
+function ci_trace_build {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "build arch: $CI_BUILD_ARCH"
+    ci_info "build system: $CI_BUILD_SYSTEM"
+    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
+        ci_info "target arch: $CI_TARGET_ARCH"
+        ci_info "target system: $CI_TARGET_SYSTEM"
+    }
+    ci_info "source directory: $CI_SRC_DIR"
+    ci_info "build directory: $CI_BUILD_DIR"
+    ci_info "install directory: $CI_INSTALL_DIR"
+    ci_info "environment option: \$CI_CMAKE: '$CI_CMAKE'"
+    ci_info "environment option: \$CI_CMAKE_GENERATOR: '$CI_CMAKE_GENERATOR'"
+    ci_info "environment option: \$CI_CMAKE_GENERATOR_PLATFORM: '$CI_CMAKE_GENERATOR_PLATFORM'"
+    ci_info "environment option: \$CI_CMAKE_BUILD_TYPE: '$CI_CMAKE_BUILD_TYPE'"
+    ci_info "environment option: \$CI_CMAKE_BUILD_FLAGS: '$CI_CMAKE_BUILD_FLAGS'"
+    ci_info "environment option: \$CI_CMAKE_TOOLCHAIN_FILE: '$CI_CMAKE_TOOLCHAIN_FILE'"
+    ci_info "environment option: \$CI_CMAKE_VARS: '$CI_CMAKE_VARS'"
+    ci_info "environment option: \$CI_CTEST: '$CI_CTEST'"
+    ci_info "environment option: \$CI_CTEST_FLAGS: '$CI_CTEST_FLAGS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_CMAKE: $(command -V "$CI_CMAKE")"
+    ci_info "executable: \$CI_CTEST: $(command -V "$CI_CTEST")"
+    [[ $CI_CC ]] && {
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    }
+    [[ $CI_AR ]] && {
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    }
+    [[ $CI_RANLIB ]] && {
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    }
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_cleanup_old_build {
+    ci_info "## START OF PRE-BUILD CLEANUP ##"
+    [[ ! -e $CI_BUILD_DIR && ! -e $CI_INSTALL_DIR ]] || {
+        ci_spawn rm -fr "$CI_BUILD_DIR"
+        ci_spawn rm -fr "$CI_INSTALL_DIR"
+    }
+    ci_info "## END OF PRE-BUILD CLEANUP ##"
+}
+
+function ci_build {
+    ci_info "## START OF BUILD ##"
+    # Adjust the CI environment variables, as needed.
+    CI_CMAKE="$(command -v "$CI_CMAKE")" || ci_err "bad or missing \$CI_CMAKE"
+    ci_spawn "$CI_CMAKE" --version
+    CI_CTEST="$(command -v "$CI_CTEST")" || ci_err "bad or missing \$CI_CTEST"
+    ci_spawn "$CI_CTEST" --version
+    [[ $CI_CMAKE_GENERATOR == *"Ninja"* ]] && {
+        CI_NINJA="$(command -v ninja)" || ci_err "bad or missing ninja, no pun intended"
+        ci_spawn "$CI_NINJA" --version
+    }
+    [[ $CI_AR ]] && {
+        # Use the full path of CI_AR to work around a mysterious CMake error.
+        CI_AR="$(command -v "$CI_AR")" || ci_err "bad or missing \$CI_AR"
+    }
+    [[ $CI_RANLIB ]] && {
+        # Use the full path of CI_RANLIB to work around a mysterious CMake error.
+        CI_RANLIB="$(command -v "$CI_RANLIB")" || ci_err "bad or missing \$CI_RANLIB"
+    }
+    # Export the CMake environment variables.
+    [[ $CI_CMAKE_GENERATOR ]] && {
+        ci_spawn export CMAKE_GENERATOR="$CI_CMAKE_GENERATOR"
+    }
+    [[ $CI_CMAKE_GENERATOR_PLATFORM ]] && {
+        ci_spawn export CMAKE_GENERATOR_PLATFORM="$CI_CMAKE_GENERATOR_PLATFORM"
+    }
+    # Initialize and populate the local arrays.
+    local all_cmake_vars=()
+    local all_cmake_build_flags=()
+    local all_ctest_flags=()
+    [[ $CI_CMAKE_TOOLCHAIN_FILE ]] && {
+        all_cmake_vars+=(-DCMAKE_TOOLCHAIN_FILE="$CI_CMAKE_TOOLCHAIN_FILE")
+    }
+    [[ $CI_CC ]] && {
+        all_cmake_vars+=(-DCMAKE_C_COMPILER="$CI_CC")
+    }
+    [[ $CI_CC_FLAGS || $CI_SANITIZERS ]] && {
+        [[ $CI_SANITIZERS ]] && CI_CC_FLAGS+="${CI_CC_FLAGS:+" "}-fsanitize=$CI_SANITIZERS"
+        all_cmake_vars+=(-DCMAKE_C_FLAGS="$CI_CC_FLAGS")
+    }
+    [[ $CI_AR ]] && {
+        all_cmake_vars+=(-DCMAKE_AR="$CI_AR")
+    }
+    [[ $CI_RANLIB ]] && {
+        all_cmake_vars+=(-DCMAKE_RANLIB="$CI_RANLIB")
+    }
+    all_cmake_vars+=(-DCMAKE_BUILD_TYPE="$CI_CMAKE_BUILD_TYPE")
+    all_cmake_vars+=(-DCMAKE_VERBOSE_MAKEFILE=ON)
+    all_cmake_vars+=($CI_CMAKE_VARS)
+    all_cmake_build_flags+=($CI_CMAKE_BUILD_FLAGS)
+    all_ctest_flags+=($CI_CTEST_FLAGS)
+    # And... build!
+    # Use $CI_BUILD_TO_SRC_RELDIR and $CI_BUILD_TO_INSTALL_RELDIR
+    # instead of $CI_SRC_DIR and $CI_INSTALL_DIR from this point onwards.
+    ci_spawn mkdir -p "$CI_BUILD_DIR"
+    ci_spawn cd "$CI_BUILD_DIR"
+    [[ $CI_BUILD_TO_SRC_RELDIR -ef $CI_SRC_DIR ]] || {
+        ci_err_internal "bad or missing \$CI_BUILD_TO_SRC_RELDIR"
+    }
+    ci_spawn mkdir -p "$CI_INSTALL_DIR"
+    [[ $CI_BUILD_TO_INSTALL_RELDIR -ef $CI_INSTALL_DIR ]] || {
+        ci_err_internal "bad or missing \$CI_BUILD_TO_INSTALL_RELDIR"
+    }
+    # Spawn "cmake ...".
+    ci_spawn "$CI_CMAKE" -DCMAKE_INSTALL_PREFIX="$CI_BUILD_TO_INSTALL_RELDIR" \
+                         "${all_cmake_vars[@]}" \
+                         "$CI_BUILD_TO_SRC_RELDIR"
+    # Spawn "cmake --build ...".
+    ci_spawn "$CI_CMAKE" --build . \
+                         --config "$CI_CMAKE_BUILD_TYPE" \
+                         "${all_cmake_build_flags[@]}"
+    ci_expr $((CI_NO_TEST)) || {
+        # Spawn "ctest" if testing is not disabled.
+        ci_spawn "$CI_CTEST" --build-config "$CI_CMAKE_BUILD_TYPE" \
+                             "${all_ctest_flags[@]}"
+    }
+    ci_expr $((CI_NO_INSTALL)) || {
+        # Spawn "cmake --build ... --target install" if installation is not disabled.
+        ci_spawn "$CI_CMAKE" --build . \
+                             --config "$CI_CMAKE_BUILD_TYPE" \
+                             --target install \
+                             "${all_cmake_build_flags[@]}"
+    }
+    ci_expr $((CI_NO_CLEAN)) || {
+        # Spawn "make --build ... --target clean" if cleaning is not disabled.
+        ci_spawn "$CI_CMAKE" --build . \
+                             --config "$CI_CMAKE_BUILD_TYPE" \
+                             --target clean \
+                             "${all_cmake_build_flags[@]}"
+    }
+    ci_info "## END OF BUILD ##"
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>]"
+    echo "options: -?|-h|--help"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    # And... go!
+    ci_init_build
+    ci_trace_build
+    [[ $# -eq 0 ]] || {
+        echo >&2 "error: unexpected argument: '$1'"
+        echo >&2 "note: this program accepts environment options only"
+        usage 2
+    }
+    ci_cleanup_old_build
+    ci_build
+}
+
+main "$@"
diff --git a/ci/ci_verify_configure.sh b/ci/ci_verify_configure.sh
new file mode 100755
index 0000000..0a2bd80
--- /dev/null
+++ b/ci/ci_verify_configure.sh
@@ -0,0 +1,163 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+CI_SRC_DIR="$CI_TOPLEVEL_DIR"
+CI_OUT_DIR="$CI_TOPLEVEL_DIR/out"
+CI_BUILD_DIR="$CI_OUT_DIR/ci_verify_configure.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.build"
+CI_INSTALL_DIR="$CI_OUT_DIR/ci_verify_configure.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.install"
+
+function ci_init_build {
+    # Ensure that the mandatory variables are initialized.
+    CI_MAKE="${CI_MAKE:-make}"
+    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] || {
+        # For native builds, set CI_CC to "cc" by default if the cc command is available.
+        # The configure script defaults CC to "gcc", which is not always a good idea.
+        [[ -x $(command -v cc) ]] && CI_CC="${CI_CC:-cc}"
+    }
+    # Ensure that the CI_ variables that cannot be customized reliably are not initialized.
+    [[ ! $CI_CONFIGURE_VARS ]] || {
+        ci_err "unsupported: \$CI_CONFIGURE_VARS='$CI_CONFIGURE_VARS'"
+    }
+    [[ ! $CI_MAKE_VARS ]] || {
+        ci_err "unsupported: \$CI_MAKE_VARS='$CI_MAKE_VARS'"
+    }
+}
+
+function ci_trace_build {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "build arch: $CI_BUILD_ARCH"
+    ci_info "build system: $CI_BUILD_SYSTEM"
+    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
+        ci_info "target arch: $CI_TARGET_ARCH"
+        ci_info "target system: $CI_TARGET_SYSTEM"
+    }
+    ci_info "source directory: $CI_SRC_DIR"
+    ci_info "build directory: $CI_BUILD_DIR"
+    ci_info "install directory: $CI_INSTALL_DIR"
+    ci_info "environment option: \$CI_CONFIGURE_FLAGS: '$CI_CONFIGURE_FLAGS'"
+    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
+    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
+    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_LD: '$CI_LD'"
+    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
+    [[ $CI_CC ]] && {
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    }
+    [[ $CI_CPP ]] && {
+        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
+    }
+    [[ $CI_AR ]] && {
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    }
+    [[ $CI_RANLIB ]] && {
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    }
+    [[ $CI_LD ]] && {
+        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
+    }
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_cleanup_old_build {
+    ci_info "## START OF PRE-BUILD CHECKUP ##"
+    ci_spawn test '!' -f "$CI_SRC_DIR/config.status" || {
+        # Warn the user, but do not delete their files.
+        ci_warn "unexpected build configuration file: '$CI_SRC_DIR/config.status'"
+        ci_warn "the configure script might fail"
+    }
+    ci_info "## END OF PRE-BUILD CHECKUP ##"
+    ci_info "## START OF PRE-BUILD CLEANUP ##"
+    [[ ! -e $CI_BUILD_DIR && ! -e $CI_INSTALL_DIR ]] || {
+        ci_spawn rm -fr "$CI_BUILD_DIR"
+        ci_spawn rm -fr "$CI_INSTALL_DIR"
+    }
+    ci_info "## END OF PRE-BUILD CLEANUP ##"
+}
+
+function ci_build {
+    ci_info "## START OF BUILD ##"
+    # Export the configure build environment.
+    [[ $CI_CC ]] && ci_spawn export CC="$CI_CC"
+    [[ $CI_CC_FLAGS ]] && ci_spawn export CFLAGS="$CI_CC_FLAGS"
+    [[ $CI_CPP ]] && ci_spawn export CPP="$CI_CPP"
+    [[ $CI_CPP_FLAGS ]] && ci_spawn export CPPFLAGS="$CI_CPP_FLAGS"
+    [[ $CI_AR ]] && ci_spawn export AR="$CI_AR"
+    [[ $CI_RANLIB ]] && ci_spawn export RANLIB="$CI_RANLIB"
+    [[ $CI_LD ]] && ci_spawn export LD="$CI_LD"
+    [[ $CI_LD_FLAGS ]] && ci_spawn export LDFLAGS="$CI_LD_FLAGS"
+    [[ $CI_SANITIZERS ]] && {
+        ci_spawn export CFLAGS="${CFLAGS:-"-O2"} -fsanitize=$CI_SANITIZERS"
+        ci_spawn export LDFLAGS="${LDFLAGS}${LDFLAGS:+" "}-fsanitize=$CI_SANITIZERS"
+    }
+    # And... build!
+    ci_spawn mkdir -p "$CI_BUILD_DIR"
+    ci_spawn cd "$CI_BUILD_DIR"
+    # Spawn "configure".
+    ci_spawn "$CI_SRC_DIR/configure" --prefix="$CI_INSTALL_DIR" $CI_CONFIGURE_FLAGS
+    # Spawn "make".
+    ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS
+    ci_expr $((CI_NO_TEST)) || {
+        # Spawn "make test" if testing is not disabled.
+        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS test
+    }
+    ci_expr $((CI_NO_INSTALL)) || {
+        # Spawn "make install" if installation is not disabled.
+        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS install
+    }
+    ci_expr $((CI_NO_CLEAN)) || {
+        # Spawn "make clean" and "make distclean" if cleaning is not disabled.
+        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS clean
+        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS distclean
+    }
+    ci_info "## END OF BUILD ##"
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>]"
+    echo "options: -?|-h|--help"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    # And... go!
+    ci_init_build
+    ci_trace_build
+    [[ $# -eq 0 ]] || {
+        echo >&2 "error: unexpected argument: '$1'"
+        echo >&2 "note: this program accepts environment options only"
+        usage 2
+    }
+    ci_cleanup_old_build
+    ci_build
+}
+
+main "$@"
diff --git a/ci/ci_verify_makefiles.sh b/ci/ci_verify_makefiles.sh
new file mode 100755
index 0000000..a0db938
--- /dev/null
+++ b/ci/ci_verify_makefiles.sh
@@ -0,0 +1,183 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+CI_SRC_DIR="$CI_TOPLEVEL_DIR"
+
+function ci_init_build {
+    # Ensure that the mandatory variables are initialized.
+    CI_MAKE="${CI_MAKE:-make}"
+    case "$CI_CC" in
+    ( *clang* )
+        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.clang"}" ;;
+    ( *gcc* )
+        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.gcc"}" ;;
+    ( * )
+        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.std"}" ;;
+    esac
+}
+
+function ci_trace_build {
+    ci_info "## START OF CONFIGURATION ##"
+    ci_info "build arch: $CI_BUILD_ARCH"
+    ci_info "build system: $CI_BUILD_SYSTEM"
+    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
+        ci_info "target arch: $CI_TARGET_ARCH"
+        ci_info "target system: $CI_TARGET_SYSTEM"
+    }
+    ci_info "source directory: $CI_SRC_DIR"
+    ci_info "environment option: \$CI_MAKEFILES: '$CI_MAKEFILES'"
+    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
+    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
+    ci_info "environment option: \$CI_MAKE_VARS: '$CI_MAKE_VARS'"
+    ci_info "environment option: \$CI_CC: '$CI_CC'"
+    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
+    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
+    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
+    ci_info "environment option: \$CI_AR: '$CI_AR'"
+    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
+    ci_info "environment option: \$CI_LD: '$CI_LD'"
+    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
+    ci_info "environment option: \$CI_LIBS: '$CI_LIBS'"
+    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
+    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
+    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
+    [[ $CI_CC ]] && {
+        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
+    }
+    [[ $CI_CPP ]] && {
+        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
+    }
+    [[ $CI_AR ]] && {
+        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
+    }
+    [[ $CI_RANLIB ]] && {
+        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
+    }
+    [[ $CI_LD ]] && {
+        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
+    }
+    ci_info "## END OF CONFIGURATION ##"
+}
+
+function ci_cleanup_old_build {
+    # Any old makefile-based build will most likely leave a mess
+    # of object files behind if interrupted, e.g., via Ctrl+C.
+    # There may be other files behind, depending on what makefile
+    # had been used. We cannot easily enumerate all of those.
+    # Fortunately, for a clean makefiles-based build, it should be
+    # sufficient to remove the old object files only.
+    ci_info "## START OF PRE-BUILD CLEANUP ##"
+    local my_file
+    find "$CI_SRC_DIR" -maxdepth 1 \( -iname "*.o" -o -iname "*.obj" \) |
+        while IFS="" read -r my_file
+        do
+            ci_spawn rm -fr "$my_file"
+        done
+    ci_info "## END OF PRE-BUILD CLEANUP ##"
+}
+
+function ci_build {
+    ci_info "## START OF BUILD ##"
+    # Initialize and populate the local arrays.
+    local all_make_flags=()
+    local all_make_vars=()
+    [[ $CI_MAKE_FLAGS ]] && {
+        all_make_flags+=($CI_MAKE_FLAGS)
+    }
+    [[ $CI_CC ]] && {
+        all_make_vars+=(CC="$CI_CC")
+    }
+    [[ $CI_CC_FLAGS || $CI_SANITIZERS ]] && {
+        [[ $CI_SANITIZERS ]] && CI_CC_FLAGS="${CI_CC_FLAGS:-"-O2"} -fsanitize=$CI_SANITIZERS"
+        all_make_vars+=(CFLAGS="$CI_CC_FLAGS")
+    }
+    [[ $CI_CPP ]] && {
+        all_make_vars+=(CPP="$CI_CPP")
+    }
+    [[ $CI_CPP_FLAGS ]] && {
+        all_make_vars+=(CPPFLAGS="$CI_CPP_FLAGS")
+    }
+    [[ $CI_AR ]] && {
+        all_make_vars+=(AR="$CI_AR")
+    }
+    [[ $CI_RANLIB ]] && {
+        all_make_vars+=(RANLIB="$CI_RANLIB")
+    }
+    [[ $CI_LD ]] && {
+        all_make_vars+=(LD="$CI_LD")
+    }
+    [[ $CI_LD_FLAGS || $CI_SANITIZERS ]] && {
+        [[ $CI_SANITIZERS ]] && CI_LD_FLAGS+="${CI_LD_FLAGS:+" "}-fsanitize=$CI_SANITIZERS"
+        all_make_vars+=(LDFLAGS="$CI_LD_FLAGS")
+    }
+    [[ $CI_LIBS ]] && {
+        all_make_vars+=(LIBS="$CI_LIBS")
+    }
+    all_make_vars+=($CI_MAKE_VARS)
+    # And... build!
+    local my_makefile
+    for my_makefile in $CI_MAKEFILES
+    do
+        ci_info "using makefile: $my_makefile"
+        # Spawn "make".
+        ci_spawn "$CI_MAKE" -f "$my_makefile" \
+                            "${all_make_flags[@]}" \
+                            "${all_make_vars[@]}"
+        ci_expr $((CI_NO_TEST)) || {
+            # Spawn "make test" if testing is not disabled.
+            ci_spawn "$CI_MAKE" -f "$my_makefile" \
+                                "${all_make_flags[@]}" \
+                                "${all_make_vars[@]}" \
+                                test
+        }
+        ci_expr $((CI_NO_CLEAN)) || {
+            # Spawn "make clean" if cleaning is not disabled.
+            ci_spawn "$CI_MAKE" -f "$my_makefile" \
+                                "${all_make_flags[@]}" \
+                                "${all_make_vars[@]}" \
+                                clean
+        }
+    done
+    ci_info "## END OF BUILD ##"
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>]"
+    echo "options: -?|-h|--help"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    # And... go!
+    ci_init_build
+    ci_trace_build
+    [[ $# -eq 0 ]] || {
+        echo >&2 "error: unexpected argument: '$1'"
+        echo >&2 "note: this program accepts environment options only"
+        usage 2
+    }
+    ci_cleanup_old_build
+    ci_build
+}
+
+main "$@"
diff --git a/ci/ci_verify_version.sh b/ci/ci_verify_version.sh
new file mode 100755
index 0000000..8199d79
--- /dev/null
+++ b/ci/ci_verify_version.sh
@@ -0,0 +1,151 @@
+#!/usr/bin/env bash
+set -o errexit -o pipefail -o posix
+
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+# shellcheck source="ci/lib/ci.lib.sh"
+source "$(dirname "$0")/lib/ci.lib.sh"
+cd "$CI_TOPLEVEL_DIR"
+
+function ci_init_shellify {
+    [[ -f $CI_SCRIPT_DIR/ci_shellify.sh ]] || {
+        ci_err_internal "missing script: '$CI_SCRIPT_DIR/ci_shellify.sh'"
+    }
+}
+
+function ci_run_shellify {
+    ci_info "shellifying:" "$@"
+    local my_result
+    "$BASH" "$CI_SCRIPT_DIR/ci_shellify.sh" "$@"
+    echo "$my_result" | "$BASH" --posix || ci_err "bad shellify output"
+    echo "$my_result"
+}
+
+function ci_verify_version {
+    ci_info "## START OF VERIFICATION ##"
+    local my_env_libpng_ver my_env_autoconf_ver my_env_cmake_ver my_expect
+    ci_init_shellify
+    my_env_libpng_ver="$(ci_run_shellify png.h)"
+    echo "$my_env_libpng_ver"
+    my_env_autoconf_ver="$(ci_run_shellify configure.ac)"
+    echo "$my_env_autoconf_ver"
+    my_env_cmake_ver="$(ci_run_shellify CMakeLists.txt)"
+    echo "$my_env_cmake_ver"
+    ci_info "## VERIFYING: png.h version definitions ##"
+    eval "$my_env_libpng_ver"
+    local my_expect="${PNG_LIBPNG_VER_MAJOR}.${PNG_LIBPNG_VER_MINOR}.${PNG_LIBPNG_VER_RELEASE}"
+    if [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect"* ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER_STRING == $my_expect*"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER_STRING != $my_expect*"
+    fi
+    my_expect=$((PNG_LIBPNG_VER_MAJOR*10000 + PNG_LIBPNG_VER_MINOR*100 + PNG_LIBPNG_VER_RELEASE))
+    if [[ "$PNG_LIBPNG_VER" == "$my_expect" ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER == $my_expect"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER != $my_expect"
+    fi
+    my_expect=$((PNG_LIBPNG_VER_MAJOR*10 + PNG_LIBPNG_VER_MINOR))
+    if [[ "$PNG_LIBPNG_VER_SHAREDLIB" == "$my_expect" ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER_SHAREDLIB == $my_expect"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER_SHAREDLIB != $my_expect"
+    fi
+    if [[ "$PNG_LIBPNG_VER_SONUM" == "$my_expect" ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER_SONUM == $my_expect"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER_SONUM != $my_expect"
+    fi
+    if [[ "$PNG_LIBPNG_VER_DLLNUM" == "$my_expect" ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER_DLLNUM == $my_expect"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER_DLLNUM != $my_expect"
+    fi
+    if [[ "$PNG_LIBPNG_VER_BUILD" == 1 ]]
+    then
+        ci_info "matched: \$PNG_LIBPNG_VER_BUILD == 1"
+    else
+        ci_err "mismatched: \$PNG_LIBPNG_VER_BUILD != 1"
+    fi
+    ci_info "## VERIFYING: png.h build definitions ##"
+    my_expect="${PNG_LIBPNG_VER_MAJOR}.${PNG_LIBPNG_VER_MINOR}.${PNG_LIBPNG_VER_RELEASE}"
+    if [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect" ]]
+    then
+        if [[ $PNG_LIBPNG_BUILD_BASE_TYPE -eq $PNG_LIBPNG_BUILD_STABLE ]]
+        then
+            ci_info "matched: \$PNG_LIBPNG_BUILD_BASE_TYPE -eq \$PNG_LIBPNG_BUILD_BETA"
+        else
+            ci_err "mismatched: \$PNG_LIBPNG_BUILD_BASE_TYPE -ne \$PNG_LIBPNG_BUILD_BETA"
+        fi
+    elif [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect".git ]]
+    then
+        if [[ $PNG_LIBPNG_BUILD_BASE_TYPE -eq $PNG_LIBPNG_BUILD_BETA ]]
+        then
+            ci_info "matched: \$PNG_LIBPNG_BUILD_BASE_TYPE -eq \$PNG_LIBPNG_BUILD_BETA"
+        else
+            ci_err "mismatched: \$PNG_LIBPNG_BUILD_BASE_TYPE -ne \$PNG_LIBPNG_BUILD_BETA"
+        fi
+    else
+        ci_err "unexpected: \$PNG_LIBPNG_VER_STRING == '$PNG_LIBPNG_VER_STRING'"
+    fi
+    ci_info "## VERIFYING: png.h type definitions ##"
+    my_expect="$(echo "png_libpng_version_${PNG_LIBPNG_VER_STRING}" | tr . _)"
+    ci_spawn grep -w -e "$my_expect" png.h
+    ci_info "## VERIFYING: configure.ac version definitions ##"
+    eval "$my_env_autoconf_ver"
+    if [[ "$PNGLIB_VERSION" == "$PNG_LIBPNG_VER_STRING" ]]
+    then
+        ci_info "matched: \$PNGLIB_VERSION == \$PNG_LIBPNG_VER_STRING"
+    else
+        ci_err "mismatched: \$PNGLIB_VERSION != \$PNG_LIBPNG_VER_STRING"
+    fi
+    ci_info "## VERIFYING: CMakeLists.txt version definitions ##"
+    eval "$my_env_cmake_ver"
+    if [[ "$PNGLIB_VERSION" == "$PNG_LIBPNG_VER_STRING" && "$PNGLIB_SUBREVISION" == 0 ]]
+    then
+        ci_info "matched: \$PNGLIB_VERSION == \$PNG_LIBPNG_VER_STRING"
+        ci_info "matched: \$PNGLIB_SUBREVISION == 0"
+    elif [[ "$PNGLIB_VERSION.$PNGLIB_SUBREVISION" == "$PNG_LIBPNG_VER_STRING" ]]
+    then
+        ci_info "matched: \$PNGLIB_VERSION.\$PNGLIB_SUBREVISION == \$PNG_LIBPNG_VER_STRING"
+    else
+        ci_err "mismatched: \$PNGLIB_VERSION != \$PNG_LIBPNG_VER_STRING"
+    fi
+    ci_info "## END OF VERIFICATION ##"
+    ci_info "success!"
+}
+
+function usage {
+    echo "usage: $CI_SCRIPT_NAME [<options>]"
+    echo "options: -?|-h|--help"
+    exit "${@:-0}"
+}
+
+function main {
+    local opt
+    while getopts ":" opt
+    do
+        # This ain't a while-loop. It only pretends to be.
+        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
+        ci_err "unknown option: '$1'"
+    done
+    shift $((OPTIND - 1))
+    [[ $# -eq 0 ]] || {
+        echo >&2 "error: unexpected argument: '$1'"
+        usage 2
+    }
+    # And... go!
+    ci_verify_version
+}
+
+main "$@"
diff --git a/ci/lib/ci.lib.sh b/ci/lib/ci.lib.sh
new file mode 100644
index 0000000..813cc09
--- /dev/null
+++ b/ci/lib/ci.lib.sh
@@ -0,0 +1,99 @@
+# Copyright (c) 2019-2024 Cosmin Truta.
+#
+# Use, modification and distribution are subject to the MIT License.
+# Please see the accompanying file LICENSE_MIT.txt
+#
+# SPDX-License-Identifier: MIT
+
+test -f "$BASH_SOURCE" || {
+    echo >&2 "warning: this module requires Bash version 3 or newer"
+}
+test "${#BASH_SOURCE[@]}" -gt 1 || {
+    echo >&2 "warning: this module should be sourced from a Bash script"
+}
+
+# Reset the locale to avoid surprises from locale-dependent commands.
+export LC_ALL=C
+export LANG=C
+export LANGUAGE=C
+
+# Reset CDPATH to avoid surprises from the "cd" command.
+export CDPATH=""
+
+# Initialize the global constants CI_SCRIPT_{NAME,DIR} and CI_TOPLEVEL_DIR.
+CI_SCRIPT_NAME="$(basename -- "$0")"
+CI_SCRIPT_DIR="$(cd "$(dirname -- "$0")" && pwd)"
+CI_TOPLEVEL_DIR="$(cd "$(dirname -- "${BASH_SOURCE[0]}")/../.." && pwd)"
+
+# Initialize the global constants CI_BUILD_{...} for the host build platform.
+CI_BUILD_ARCH="${CI_BUILD_ARCH:-"$(uname -m | tr 'A-Z/\.-' 'a-z____')"}"
+CI_BUILD_SYSTEM="${CI_BUILD_SYSTEM:-"$(uname -s | tr 'A-Z/\.-' 'a-z____')"}"
+
+# Initialize the global constants CI_TARGET_{...} for the target platform.
+CI_TARGET_ARCH="${CI_TARGET_ARCH:-"$CI_BUILD_ARCH"}"
+CI_TARGET_SYSTEM="${CI_TARGET_SYSTEM:-"$CI_BUILD_SYSTEM"}"
+
+function ci_info {
+    printf >&2 "%s: %s\\n" "$CI_SCRIPT_NAME" "$*"
+}
+
+function ci_warn {
+    printf >&2 "%s: warning: %s\\n" "$CI_SCRIPT_NAME" "$*"
+}
+
+function ci_err {
+    printf >&2 "%s: error: %s\\n" "$CI_SCRIPT_NAME" "$*"
+    exit 2
+}
+
+function ci_err_internal {
+    printf >&2 "%s: internal error: %s\\n" "$CI_SCRIPT_NAME" "$*"
+    printf >&2 "ABORTED\\n"
+    # Exit with the conventional SIGABRT code.
+    exit 134
+}
+
+function ci_expr {
+    if [[ ${*:-0} == [0-9] ]]
+    then
+        # This is the same as in the else-branch below, albeit much faster
+        # for our intended use cases.
+        return $((!$1))
+    else
+        # The funny-looking compound command "... && return $? || return $?"
+        # allows the execution to continue uninterrupted under "set -e".
+        expr >/dev/null "$@" && return $? || return $?
+    fi
+}
+
+function ci_spawn {
+    printf >&2 "%s: executing:" "$CI_SCRIPT_NAME"
+    printf >&2 " %q" "$@"
+    printf >&2 "\\n"
+    "$@"
+}
+
+# Ensure that the internal initialization is correct.
+[[ $CI_TOPLEVEL_DIR/ci/lib/ci.lib.sh -ef ${BASH_SOURCE[0]} ]] || {
+    ci_err_internal "bad or missing \$CI_TOPLEVEL_DIR"
+}
+[[ $CI_SCRIPT_DIR/$CI_SCRIPT_NAME -ef $0 ]] || {
+    ci_err_internal "bad or missing \$CI_SCRIPT_DIR/\$CI_SCRIPT_NAME"
+}
+[[ $CI_BUILD_ARCH && $CI_BUILD_SYSTEM ]] || {
+    ci_err_internal "missing \$CI_BUILD_ARCH or \$CI_BUILD_SYSTEM"
+}
+[[ $CI_TARGET_ARCH && $CI_TARGET_SYSTEM ]] || {
+    ci_err_internal "missing \$CI_TARGET_ARCH or \$CI_TARGET_SYSTEM"
+}
+
+# Ensure that the user initialization is correct.
+[[ ${CI_NO_TEST:-0} == [01] ]] || {
+    ci_err "bad boolean option: \$CI_NO_TEST: '$CI_NO_TEST'"
+}
+[[ ${CI_NO_INSTALL:-0} == [01] ]] || {
+    ci_err "bad boolean option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
+}
+[[ ${CI_NO_CLEAN:-0} == [01] ]] || {
+    ci_err "bad boolean option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
+}
diff --git a/compile b/compile
index 99e5052..df363c8 100755
--- a/compile
+++ b/compile
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 # Written by Tom Tromey <tromey@cygnus.com>.
 #
 # This program is free software; you can redistribute it and/or modify
@@ -53,7 +53,7 @@
 	  MINGW*)
 	    file_conv=mingw
 	    ;;
-	  CYGWIN*)
+	  CYGWIN* | MSYS*)
 	    file_conv=cygwin
 	    ;;
 	  *)
@@ -67,7 +67,7 @@
 	mingw/*)
 	  file=`cmd //C echo "$file " | sed -e 's/"\(.*\) " *$/\1/'`
 	  ;;
-	cygwin/*)
+	cygwin/* | msys/*)
 	  file=`cygpath -m "$file" || echo "$file"`
 	  ;;
 	wine/*)
diff --git a/config.guess b/config.guess
index 256083a..cdfc439 100755
--- a/config.guess
+++ b/config.guess
@@ -1,12 +1,14 @@
 #! /bin/sh
 # Attempt to guess a canonical system name.
-#   Copyright 1992-2018 Free Software Foundation, Inc.
+#   Copyright 1992-2023 Free Software Foundation, Inc.
 
-timestamp='2018-03-08'
+# shellcheck disable=SC2006,SC2268 # see below for rationale
+
+timestamp='2023-08-22'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
+# the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful, but
@@ -27,17 +29,25 @@
 # Originally written by Per Bothner; maintained since 2000 by Ben Elliston.
 #
 # You can get the latest version of this script from:
-# https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess
+# https://git.savannah.gnu.org/cgit/config.git/plain/config.guess
 #
 # Please send patches to <config-patches@gnu.org>.
 
 
+# The "shellcheck disable" line above the timestamp inhibits complaints
+# about features and limitations of the classic Bourne shell that were
+# superseded or lifted in POSIX.  However, this script identifies a wide
+# variety of pre-POSIX systems that do not have POSIX shells at all, and
+# even some reasonably current systems (Solaris 10 as case-in-point) still
+# have a pre-POSIX /bin/sh.
+
+
 me=`echo "$0" | sed -e 's,.*/,,'`
 
 usage="\
 Usage: $0 [OPTION]
 
-Output the configuration name of the system \`$me' is run on.
+Output the configuration name of the system '$me' is run on.
 
 Options:
   -h, --help         print this help, then exit
@@ -50,13 +60,13 @@
 GNU config.guess ($timestamp)
 
 Originally written by Per Bothner.
-Copyright 1992-2018 Free Software Foundation, Inc.
+Copyright 1992-2023 Free Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
 
 help="
-Try \`$me --help' for more information."
+Try '$me --help' for more information."
 
 # Parse command line
 while test $# -gt 0 ; do
@@ -84,85 +94,107 @@
   exit 1
 fi
 
-trap 'exit 1' 1 2 15
+# Just in case it came from the environment.
+GUESS=
 
 # CC_FOR_BUILD -- compiler used by this script. Note that the use of a
 # compiler to aid in system detection is discouraged as it requires
 # temporary files to be created and, as you can see below, it is a
 # headache to deal with in a portable fashion.
 
-# Historically, `CC_FOR_BUILD' used to be named `HOST_CC'. We still
-# use `HOST_CC' if defined, but it is deprecated.
+# Historically, 'CC_FOR_BUILD' used to be named 'HOST_CC'. We still
+# use 'HOST_CC' if defined, but it is deprecated.
 
 # Portable tmp directory creation inspired by the Autoconf team.
 
-set_cc_for_build='
-trap "exitcode=\$?; (rm -f \$tmpfiles 2>/dev/null; rmdir \$tmp 2>/dev/null) && exit \$exitcode" 0 ;
-trap "rm -f \$tmpfiles 2>/dev/null; rmdir \$tmp 2>/dev/null; exit 1" 1 2 13 15 ;
-: ${TMPDIR=/tmp} ;
- { tmp=`(umask 077 && mktemp -d "$TMPDIR/cgXXXXXX") 2>/dev/null` && test -n "$tmp" && test -d "$tmp" ; } ||
- { test -n "$RANDOM" && tmp=$TMPDIR/cg$$-$RANDOM && (umask 077 && mkdir $tmp) ; } ||
- { tmp=$TMPDIR/cg-$$ && (umask 077 && mkdir $tmp) && echo "Warning: creating insecure temp directory" >&2 ; } ||
- { echo "$me: cannot create a temporary directory in $TMPDIR" >&2 ; exit 1 ; } ;
-dummy=$tmp/dummy ;
-tmpfiles="$dummy.c $dummy.o $dummy.rel $dummy" ;
-case $CC_FOR_BUILD,$HOST_CC,$CC in
- ,,)    echo "int x;" > "$dummy.c" ;
-	for c in cc gcc c89 c99 ; do
-	  if ($c -c -o "$dummy.o" "$dummy.c") >/dev/null 2>&1 ; then
-	     CC_FOR_BUILD="$c"; break ;
-	  fi ;
-	done ;
-	if test x"$CC_FOR_BUILD" = x ; then
-	  CC_FOR_BUILD=no_compiler_found ;
-	fi
-	;;
- ,,*)   CC_FOR_BUILD=$CC ;;
- ,*,*)  CC_FOR_BUILD=$HOST_CC ;;
-esac ; set_cc_for_build= ;'
+tmp=
+# shellcheck disable=SC2172
+trap 'test -z "$tmp" || rm -fr "$tmp"' 0 1 2 13 15
+
+set_cc_for_build() {
+    # prevent multiple calls if $tmp is already set
+    test "$tmp" && return 0
+    : "${TMPDIR=/tmp}"
+    # shellcheck disable=SC2039,SC3028
+    { tmp=`(umask 077 && mktemp -d "$TMPDIR/cgXXXXXX") 2>/dev/null` && test -n "$tmp" && test -d "$tmp" ; } ||
+	{ test -n "$RANDOM" && tmp=$TMPDIR/cg$$-$RANDOM && (umask 077 && mkdir "$tmp" 2>/dev/null) ; } ||
+	{ tmp=$TMPDIR/cg-$$ && (umask 077 && mkdir "$tmp" 2>/dev/null) && echo "Warning: creating insecure temp directory" >&2 ; } ||
+	{ echo "$me: cannot create a temporary directory in $TMPDIR" >&2 ; exit 1 ; }
+    dummy=$tmp/dummy
+    case ${CC_FOR_BUILD-},${HOST_CC-},${CC-} in
+	,,)    echo "int x;" > "$dummy.c"
+	       for driver in cc gcc c89 c99 ; do
+		   if ($driver -c -o "$dummy.o" "$dummy.c") >/dev/null 2>&1 ; then
+		       CC_FOR_BUILD=$driver
+		       break
+		   fi
+	       done
+	       if test x"$CC_FOR_BUILD" = x ; then
+		   CC_FOR_BUILD=no_compiler_found
+	       fi
+	       ;;
+	,,*)   CC_FOR_BUILD=$CC ;;
+	,*,*)  CC_FOR_BUILD=$HOST_CC ;;
+    esac
+}
 
 # This is needed to find uname on a Pyramid OSx when run in the BSD universe.
 # (ghazi@noc.rutgers.edu 1994-08-24)
-if (test -f /.attbin/uname) >/dev/null 2>&1 ; then
+if test -f /.attbin/uname ; then
 	PATH=$PATH:/.attbin ; export PATH
 fi
 
 UNAME_MACHINE=`(uname -m) 2>/dev/null` || UNAME_MACHINE=unknown
 UNAME_RELEASE=`(uname -r) 2>/dev/null` || UNAME_RELEASE=unknown
-UNAME_SYSTEM=`(uname -s) 2>/dev/null`  || UNAME_SYSTEM=unknown
+UNAME_SYSTEM=`(uname -s) 2>/dev/null` || UNAME_SYSTEM=unknown
 UNAME_VERSION=`(uname -v) 2>/dev/null` || UNAME_VERSION=unknown
 
-case "$UNAME_SYSTEM" in
+case $UNAME_SYSTEM in
 Linux|GNU|GNU/*)
-	# If the system lacks a compiler, then just pick glibc.
-	# We could probably try harder.
-	LIBC=gnu
+	LIBC=unknown
 
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	cat <<-EOF > "$dummy.c"
+	#if defined(__ANDROID__)
+	LIBC=android
+	#else
 	#include <features.h>
 	#if defined(__UCLIBC__)
 	LIBC=uclibc
 	#elif defined(__dietlibc__)
 	LIBC=dietlibc
-	#else
+	#elif defined(__GLIBC__)
 	LIBC=gnu
+	#else
+	#include <stdarg.h>
+	/* First heuristic to detect musl libc.  */
+	#ifdef __DEFINED_va_list
+	LIBC=musl
+	#endif
+	#endif
 	#endif
 	EOF
-	eval "`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^LIBC' | sed 's, ,,g'`"
+	cc_set_libc=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^LIBC' | sed 's, ,,g'`
+	eval "$cc_set_libc"
 
-	# If ldd exists, use it to detect musl libc.
-	if command -v ldd >/dev/null && \
-		ldd --version 2>&1 | grep -q ^musl
-	then
-	    LIBC=musl
+	# Second heuristic to detect musl libc.
+	if [ "$LIBC" = unknown ] &&
+	   command -v ldd >/dev/null &&
+	   ldd --version 2>&1 | grep -q ^musl; then
+		LIBC=musl
+	fi
+
+	# If the system lacks a compiler, then just pick glibc.
+	# We could probably try harder.
+	if [ "$LIBC" = unknown ]; then
+		LIBC=gnu
 	fi
 	;;
 esac
 
 # Note: order is significant - the case branches are not exclusive.
 
-case "$UNAME_MACHINE:$UNAME_SYSTEM:$UNAME_RELEASE:$UNAME_VERSION" in
+case $UNAME_MACHINE:$UNAME_SYSTEM:$UNAME_RELEASE:$UNAME_VERSION in
     *:NetBSD:*:*)
 	# NetBSD (nbsd) targets should (where applicable) match one or
 	# more of the tuples: *-*-netbsdelf*, *-*-netbsdaout*,
@@ -174,12 +206,12 @@
 	#
 	# Note: NetBSD doesn't particularly care about the vendor
 	# portion of the name.  We always set it to "unknown".
-	sysctl="sysctl -n hw.machine_arch"
 	UNAME_MACHINE_ARCH=`(uname -p 2>/dev/null || \
-	    "/sbin/$sysctl" 2>/dev/null || \
-	    "/usr/sbin/$sysctl" 2>/dev/null || \
+	    /sbin/sysctl -n hw.machine_arch 2>/dev/null || \
+	    /usr/sbin/sysctl -n hw.machine_arch 2>/dev/null || \
 	    echo unknown)`
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
+	    aarch64eb) machine=aarch64_be-unknown ;;
 	    armeb) machine=armeb-unknown ;;
 	    arm*) machine=arm-unknown ;;
 	    sh3el) machine=shl-unknown ;;
@@ -188,18 +220,18 @@
 	    earmv*)
 		arch=`echo "$UNAME_MACHINE_ARCH" | sed -e 's,^e\(armv[0-9]\).*$,\1,'`
 		endian=`echo "$UNAME_MACHINE_ARCH" | sed -ne 's,^.*\(eb\)$,\1,p'`
-		machine="${arch}${endian}"-unknown
+		machine=${arch}${endian}-unknown
 		;;
-	    *) machine="$UNAME_MACHINE_ARCH"-unknown ;;
+	    *) machine=$UNAME_MACHINE_ARCH-unknown ;;
 	esac
 	# The Operating System including object format, if it has switched
 	# to ELF recently (or will in the future) and ABI.
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
 	    earm*)
 		os=netbsdelf
 		;;
 	    arm*|i386|m68k|ns32k|sh3*|sparc|vax)
-		eval "$set_cc_for_build"
+		set_cc_for_build
 		if echo __ELF__ | $CC_FOR_BUILD -E - 2>/dev/null \
 			| grep -q __ELF__
 		then
@@ -215,7 +247,7 @@
 		;;
 	esac
 	# Determine ABI tags.
-	case "$UNAME_MACHINE_ARCH" in
+	case $UNAME_MACHINE_ARCH in
 	    earm*)
 		expr='s/^earmv[0-9]/-eabi/;s/eb$//'
 		abi=`echo "$UNAME_MACHINE_ARCH" | sed -e "$expr"`
@@ -226,7 +258,7 @@
 	# thus, need a distinct triplet. However, they do not need
 	# kernel version information, so it can be replaced with a
 	# suitable tag, in the style of linux-gnu.
-	case "$UNAME_VERSION" in
+	case $UNAME_VERSION in
 	    Debian*)
 		release='-gnu'
 		;;
@@ -237,45 +269,57 @@
 	# Since CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM:
 	# contains redundant information, the shorter form:
 	# CPU_TYPE-MANUFACTURER-OPERATING_SYSTEM is used.
-	echo "$machine-${os}${release}${abi}"
-	exit ;;
+	GUESS=$machine-${os}${release}${abi-}
+	;;
     *:Bitrig:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/Bitrig.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-bitrig"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-bitrig$UNAME_RELEASE
+	;;
     *:OpenBSD:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/OpenBSD.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-openbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-openbsd$UNAME_RELEASE
+	;;
+    *:SecBSD:*:*)
+	UNAME_MACHINE_ARCH=`arch | sed 's/SecBSD.//'`
+	GUESS=$UNAME_MACHINE_ARCH-unknown-secbsd$UNAME_RELEASE
+	;;
     *:LibertyBSD:*:*)
 	UNAME_MACHINE_ARCH=`arch | sed 's/^.*BSD\.//'`
-	echo "$UNAME_MACHINE_ARCH"-unknown-libertybsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE_ARCH-unknown-libertybsd$UNAME_RELEASE
+	;;
     *:MidnightBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-midnightbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-midnightbsd$UNAME_RELEASE
+	;;
     *:ekkoBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-ekkobsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-ekkobsd$UNAME_RELEASE
+	;;
     *:SolidBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-solidbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-solidbsd$UNAME_RELEASE
+	;;
+    *:OS108:*:*)
+	GUESS=$UNAME_MACHINE-unknown-os108_$UNAME_RELEASE
+	;;
     macppc:MirBSD:*:*)
-	echo powerpc-unknown-mirbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-unknown-mirbsd$UNAME_RELEASE
+	;;
     *:MirBSD:*:*)
-	echo "$UNAME_MACHINE"-unknown-mirbsd"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-mirbsd$UNAME_RELEASE
+	;;
     *:Sortix:*:*)
-	echo "$UNAME_MACHINE"-unknown-sortix
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-sortix
+	;;
+    *:Twizzler:*:*)
+	GUESS=$UNAME_MACHINE-unknown-twizzler
+	;;
     *:Redox:*:*)
-	echo "$UNAME_MACHINE"-unknown-redox
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-redox
+	;;
     mips:OSF1:*.*)
-        echo mips-dec-osf1
-        exit ;;
+	GUESS=mips-dec-osf1
+	;;
     alpha:OSF1:*:*)
+	# Reset EXIT trap before exiting to avoid spurious non-zero exit code.
+	trap '' 0
 	case $UNAME_RELEASE in
 	*4.0)
 		UNAME_RELEASE=`/usr/sbin/sizer -v | awk '{print $3}'`
@@ -289,7 +333,7 @@
 	# covers most systems running today.  This code pipes the CPU
 	# types through head -n 1, so we only detect the type of CPU 0.
 	ALPHA_CPU_TYPE=`/usr/sbin/psrinfo -v | sed -n -e 's/^  The alpha \(.*\) processor.*$/\1/p' | head -n 1`
-	case "$ALPHA_CPU_TYPE" in
+	case $ALPHA_CPU_TYPE in
 	    "EV4 (21064)")
 		UNAME_MACHINE=alpha ;;
 	    "EV4.5 (21064)")
@@ -326,117 +370,121 @@
 	# A Tn.n version is a released field test version.
 	# A Xn.n version is an unreleased experimental baselevel.
 	# 1.2 uses "1.2" for uname -r.
-	echo "$UNAME_MACHINE"-dec-osf"`echo "$UNAME_RELEASE" | sed -e 's/^[PVTX]//' | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`"
-	# Reset EXIT trap before exiting to avoid spurious non-zero exit code.
-	exitcode=$?
-	trap '' 0
-	exit $exitcode ;;
+	OSF_REL=`echo "$UNAME_RELEASE" | sed -e 's/^[PVTX]//' | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`
+	GUESS=$UNAME_MACHINE-dec-osf$OSF_REL
+	;;
     Amiga*:UNIX_System_V:4.0:*)
-	echo m68k-unknown-sysv4
-	exit ;;
+	GUESS=m68k-unknown-sysv4
+	;;
     *:[Aa]miga[Oo][Ss]:*:*)
-	echo "$UNAME_MACHINE"-unknown-amigaos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-amigaos
+	;;
     *:[Mm]orph[Oo][Ss]:*:*)
-	echo "$UNAME_MACHINE"-unknown-morphos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-morphos
+	;;
     *:OS/390:*:*)
-	echo i370-ibm-openedition
-	exit ;;
+	GUESS=i370-ibm-openedition
+	;;
     *:z/VM:*:*)
-	echo s390-ibm-zvmoe
-	exit ;;
+	GUESS=s390-ibm-zvmoe
+	;;
     *:OS400:*:*)
-	echo powerpc-ibm-os400
-	exit ;;
+	GUESS=powerpc-ibm-os400
+	;;
     arm:RISC*:1.[012]*:*|arm:riscix:1.[012]*:*)
-	echo arm-acorn-riscix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=arm-acorn-riscix$UNAME_RELEASE
+	;;
     arm*:riscos:*:*|arm*:RISCOS:*:*)
-	echo arm-unknown-riscos
-	exit ;;
+	GUESS=arm-unknown-riscos
+	;;
     SR2?01:HI-UX/MPP:*:* | SR8000:HI-UX/MPP:*:*)
-	echo hppa1.1-hitachi-hiuxmpp
-	exit ;;
+	GUESS=hppa1.1-hitachi-hiuxmpp
+	;;
     Pyramid*:OSx*:*:* | MIS*:OSx*:*:* | MIS*:SMP_DC-OSx*:*:*)
 	# akee@wpdis03.wpafb.af.mil (Earle F. Ake) contributed MIS and NILE.
-	if test "`(/bin/universe) 2>/dev/null`" = att ; then
-		echo pyramid-pyramid-sysv3
-	else
-		echo pyramid-pyramid-bsd
-	fi
-	exit ;;
+	case `(/bin/universe) 2>/dev/null` in
+	    att) GUESS=pyramid-pyramid-sysv3 ;;
+	    *)   GUESS=pyramid-pyramid-bsd   ;;
+	esac
+	;;
     NILE*:*:*:dcosx)
-	echo pyramid-pyramid-svr4
-	exit ;;
+	GUESS=pyramid-pyramid-svr4
+	;;
     DRS?6000:unix:4.0:6*)
-	echo sparc-icl-nx6
-	exit ;;
+	GUESS=sparc-icl-nx6
+	;;
     DRS?6000:UNIX_SV:4.2*:7* | DRS?6000:isis:4.2*:7*)
 	case `/usr/bin/uname -p` in
-	    sparc) echo sparc-icl-nx7; exit ;;
-	esac ;;
+	    sparc) GUESS=sparc-icl-nx7 ;;
+	esac
+	;;
     s390x:SunOS:*:*)
-	echo "$UNAME_MACHINE"-ibm-solaris2"`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=$UNAME_MACHINE-ibm-solaris2$SUN_REL
+	;;
     sun4H:SunOS:5.*:*)
-	echo sparc-hal-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-hal-solaris2$SUN_REL
+	;;
     sun4*:SunOS:5.*:* | tadpole*:SunOS:5.*:*)
-	echo sparc-sun-solaris2"`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-sun-solaris2$SUN_REL
+	;;
     i86pc:AuroraUX:5.*:* | i86xen:AuroraUX:5.*:*)
-	echo i386-pc-auroraux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=i386-pc-auroraux$UNAME_RELEASE
+	;;
     i86pc:SunOS:5.*:* | i86xen:SunOS:5.*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	SUN_ARCH=i386
 	# If there is a compiler, see if it is configured for 64-bit objects.
 	# Note that the Sun cc does not turn __LP64__ into 1 like gcc does.
 	# This test works for both compilers.
-	if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
 	    if (echo '#ifdef __amd64'; echo IS_64BIT_ARCH; echo '#endif') | \
-		(CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		(CCOPTS="" $CC_FOR_BUILD -m64 -E - 2>/dev/null) | \
 		grep IS_64BIT_ARCH >/dev/null
 	    then
 		SUN_ARCH=x86_64
 	    fi
 	fi
-	echo "$SUN_ARCH"-pc-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=$SUN_ARCH-pc-solaris2$SUN_REL
+	;;
     sun4*:SunOS:6*:*)
 	# According to config.sub, this is the proper way to canonicalize
 	# SunOS6.  Hard to guess exactly what SunOS6 will be like, but
 	# it's likely to be more like Solaris than SunOS4.
-	echo sparc-sun-solaris3"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=sparc-sun-solaris3$SUN_REL
+	;;
     sun4*:SunOS:*:*)
-	case "`/usr/bin/arch -k`" in
+	case `/usr/bin/arch -k` in
 	    Series*|S4*)
 		UNAME_RELEASE=`uname -v`
 		;;
 	esac
-	# Japanese Language versions have a version number like `4.1.3-JL'.
-	echo sparc-sun-sunos"`echo "$UNAME_RELEASE"|sed -e 's/-/_/'`"
-	exit ;;
+	# Japanese Language versions have a version number like '4.1.3-JL'.
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/-/_/'`
+	GUESS=sparc-sun-sunos$SUN_REL
+	;;
     sun3*:SunOS:*:*)
-	echo m68k-sun-sunos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-sun-sunos$UNAME_RELEASE
+	;;
     sun*:*:4.2BSD:*)
 	UNAME_RELEASE=`(sed 1q /etc/motd | awk '{print substr($5,1,3)}') 2>/dev/null`
 	test "x$UNAME_RELEASE" = x && UNAME_RELEASE=3
-	case "`/bin/arch`" in
+	case `/bin/arch` in
 	    sun3)
-		echo m68k-sun-sunos"$UNAME_RELEASE"
+		GUESS=m68k-sun-sunos$UNAME_RELEASE
 		;;
 	    sun4)
-		echo sparc-sun-sunos"$UNAME_RELEASE"
+		GUESS=sparc-sun-sunos$UNAME_RELEASE
 		;;
 	esac
-	exit ;;
+	;;
     aushp:SunOS:*:*)
-	echo sparc-auspex-sunos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-auspex-sunos$UNAME_RELEASE
+	;;
     # The situation for MiNT is a little confusing.  The machine name
     # can be virtually everything (everything which is not
     # "atarist" or "atariste" at least should have a processor
@@ -446,43 +494,43 @@
     # MiNT.  But MiNT is downward compatible to TOS, so this should
     # be no problem.
     atarist[e]:*MiNT:*:* | atarist[e]:*mint:*:* | atarist[e]:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     atari*:*MiNT:*:* | atari*:*mint:*:* | atarist[e]:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     *falcon*:*MiNT:*:* | *falcon*:*mint:*:* | *falcon*:*TOS:*:*)
-	echo m68k-atari-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-atari-mint$UNAME_RELEASE
+	;;
     milan*:*MiNT:*:* | milan*:*mint:*:* | *milan*:*TOS:*:*)
-	echo m68k-milan-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-milan-mint$UNAME_RELEASE
+	;;
     hades*:*MiNT:*:* | hades*:*mint:*:* | *hades*:*TOS:*:*)
-	echo m68k-hades-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-hades-mint$UNAME_RELEASE
+	;;
     *:*MiNT:*:* | *:*mint:*:* | *:*TOS:*:*)
-	echo m68k-unknown-mint"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-unknown-mint$UNAME_RELEASE
+	;;
     m68k:machten:*:*)
-	echo m68k-apple-machten"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-apple-machten$UNAME_RELEASE
+	;;
     powerpc:machten:*:*)
-	echo powerpc-apple-machten"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-apple-machten$UNAME_RELEASE
+	;;
     RISC*:Mach:*:*)
-	echo mips-dec-mach_bsd4.3
-	exit ;;
+	GUESS=mips-dec-mach_bsd4.3
+	;;
     RISC*:ULTRIX:*:*)
-	echo mips-dec-ultrix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-dec-ultrix$UNAME_RELEASE
+	;;
     VAX*:ULTRIX*:*:*)
-	echo vax-dec-ultrix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=vax-dec-ultrix$UNAME_RELEASE
+	;;
     2020:CLIX:*:* | 2430:CLIX:*:*)
-	echo clipper-intergraph-clix"$UNAME_RELEASE"
-	exit ;;
+	GUESS=clipper-intergraph-clix$UNAME_RELEASE
+	;;
     mips:*:*:UMIPS | mips:*:*:RISCos)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	sed 's/^	//' << EOF > "$dummy.c"
 #ifdef __cplusplus
 #include <stdio.h>  /* for printf() prototype */
@@ -508,78 +556,79 @@
 	  dummyarg=`echo "$UNAME_RELEASE" | sed -n 's/\([0-9]*\).*/\1/p'` &&
 	  SYSTEM_NAME=`"$dummy" "$dummyarg"` &&
 	    { echo "$SYSTEM_NAME"; exit; }
-	echo mips-mips-riscos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-mips-riscos$UNAME_RELEASE
+	;;
     Motorola:PowerMAX_OS:*:*)
-	echo powerpc-motorola-powermax
-	exit ;;
+	GUESS=powerpc-motorola-powermax
+	;;
     Motorola:*:4.3:PL8-*)
-	echo powerpc-harris-powermax
-	exit ;;
+	GUESS=powerpc-harris-powermax
+	;;
     Night_Hawk:*:*:PowerMAX_OS | Synergy:PowerMAX_OS:*:*)
-	echo powerpc-harris-powermax
-	exit ;;
+	GUESS=powerpc-harris-powermax
+	;;
     Night_Hawk:Power_UNIX:*:*)
-	echo powerpc-harris-powerunix
-	exit ;;
+	GUESS=powerpc-harris-powerunix
+	;;
     m88k:CX/UX:7*:*)
-	echo m88k-harris-cxux7
-	exit ;;
+	GUESS=m88k-harris-cxux7
+	;;
     m88k:*:4*:R4*)
-	echo m88k-motorola-sysv4
-	exit ;;
+	GUESS=m88k-motorola-sysv4
+	;;
     m88k:*:3*:R3*)
-	echo m88k-motorola-sysv3
-	exit ;;
+	GUESS=m88k-motorola-sysv3
+	;;
     AViiON:dgux:*:*)
 	# DG/UX returns AViiON for all architectures
 	UNAME_PROCESSOR=`/usr/bin/uname -p`
-	if [ "$UNAME_PROCESSOR" = mc88100 ] || [ "$UNAME_PROCESSOR" = mc88110 ]
+	if test "$UNAME_PROCESSOR" = mc88100 || test "$UNAME_PROCESSOR" = mc88110
 	then
-	    if [ "$TARGET_BINARY_INTERFACE"x = m88kdguxelfx ] || \
-	       [ "$TARGET_BINARY_INTERFACE"x = x ]
+	    if test "$TARGET_BINARY_INTERFACE"x = m88kdguxelfx || \
+	       test "$TARGET_BINARY_INTERFACE"x = x
 	    then
-		echo m88k-dg-dgux"$UNAME_RELEASE"
+		GUESS=m88k-dg-dgux$UNAME_RELEASE
 	    else
-		echo m88k-dg-dguxbcs"$UNAME_RELEASE"
+		GUESS=m88k-dg-dguxbcs$UNAME_RELEASE
 	    fi
 	else
-	    echo i586-dg-dgux"$UNAME_RELEASE"
+	    GUESS=i586-dg-dgux$UNAME_RELEASE
 	fi
-	exit ;;
+	;;
     M88*:DolphinOS:*:*)	# DolphinOS (SVR3)
-	echo m88k-dolphin-sysv3
-	exit ;;
+	GUESS=m88k-dolphin-sysv3
+	;;
     M88*:*:R3*:*)
 	# Delta 88k system running SVR3
-	echo m88k-motorola-sysv3
-	exit ;;
+	GUESS=m88k-motorola-sysv3
+	;;
     XD88*:*:*:*) # Tektronix XD88 system running UTekV (SVR3)
-	echo m88k-tektronix-sysv3
-	exit ;;
+	GUESS=m88k-tektronix-sysv3
+	;;
     Tek43[0-9][0-9]:UTek:*:*) # Tektronix 4300 system running UTek (BSD)
-	echo m68k-tektronix-bsd
-	exit ;;
+	GUESS=m68k-tektronix-bsd
+	;;
     *:IRIX*:*:*)
-	echo mips-sgi-irix"`echo "$UNAME_RELEASE"|sed -e 's/-/_/g'`"
-	exit ;;
+	IRIX_REL=`echo "$UNAME_RELEASE" | sed -e 's/-/_/g'`
+	GUESS=mips-sgi-irix$IRIX_REL
+	;;
     ????????:AIX?:[12].1:2)   # AIX 2.2.1 or AIX 2.1.1 is RT/PC AIX.
-	echo romp-ibm-aix     # uname -m gives an 8 hex-code CPU id
-	exit ;;               # Note that: echo "'`uname -s`'" gives 'AIX '
+	GUESS=romp-ibm-aix    # uname -m gives an 8 hex-code CPU id
+	;;                    # Note that: echo "'`uname -s`'" gives 'AIX '
     i*86:AIX:*:*)
-	echo i386-ibm-aix
-	exit ;;
+	GUESS=i386-ibm-aix
+	;;
     ia64:AIX:*:*)
-	if [ -x /usr/bin/oslevel ] ; then
+	if test -x /usr/bin/oslevel ; then
 		IBM_REV=`/usr/bin/oslevel`
 	else
-		IBM_REV="$UNAME_VERSION.$UNAME_RELEASE"
+		IBM_REV=$UNAME_VERSION.$UNAME_RELEASE
 	fi
-	echo "$UNAME_MACHINE"-ibm-aix"$IBM_REV"
-	exit ;;
+	GUESS=$UNAME_MACHINE-ibm-aix$IBM_REV
+	;;
     *:AIX:2:3)
 	if grep bos325 /usr/include/stdio.h >/dev/null 2>&1; then
-		eval "$set_cc_for_build"
+		set_cc_for_build
 		sed 's/^		//' << EOF > "$dummy.c"
 		#include <sys/systemcfg.h>
 
@@ -593,16 +642,16 @@
 EOF
 		if $CC_FOR_BUILD -o "$dummy" "$dummy.c" && SYSTEM_NAME=`"$dummy"`
 		then
-			echo "$SYSTEM_NAME"
+			GUESS=$SYSTEM_NAME
 		else
-			echo rs6000-ibm-aix3.2.5
+			GUESS=rs6000-ibm-aix3.2.5
 		fi
 	elif grep bos324 /usr/include/stdio.h >/dev/null 2>&1; then
-		echo rs6000-ibm-aix3.2.4
+		GUESS=rs6000-ibm-aix3.2.4
 	else
-		echo rs6000-ibm-aix3.2
+		GUESS=rs6000-ibm-aix3.2
 	fi
-	exit ;;
+	;;
     *:AIX:*:[4567])
 	IBM_CPU_ID=`/usr/sbin/lsdev -C -c processor -S available | sed 1q | awk '{ print $1 }'`
 	if /usr/sbin/lsattr -El "$IBM_CPU_ID" | grep ' POWER' >/dev/null 2>&1; then
@@ -610,57 +659,57 @@
 	else
 		IBM_ARCH=powerpc
 	fi
-	if [ -x /usr/bin/lslpp ] ; then
-		IBM_REV=`/usr/bin/lslpp -Lqc bos.rte.libc |
+	if test -x /usr/bin/lslpp ; then
+		IBM_REV=`/usr/bin/lslpp -Lqc bos.rte.libc | \
 			   awk -F: '{ print $3 }' | sed s/[0-9]*$/0/`
 	else
-		IBM_REV="$UNAME_VERSION.$UNAME_RELEASE"
+		IBM_REV=$UNAME_VERSION.$UNAME_RELEASE
 	fi
-	echo "$IBM_ARCH"-ibm-aix"$IBM_REV"
-	exit ;;
+	GUESS=$IBM_ARCH-ibm-aix$IBM_REV
+	;;
     *:AIX:*:*)
-	echo rs6000-ibm-aix
-	exit ;;
+	GUESS=rs6000-ibm-aix
+	;;
     ibmrt:4.4BSD:*|romp-ibm:4.4BSD:*)
-	echo romp-ibm-bsd4.4
-	exit ;;
+	GUESS=romp-ibm-bsd4.4
+	;;
     ibmrt:*BSD:*|romp-ibm:BSD:*)            # covers RT/PC BSD and
-	echo romp-ibm-bsd"$UNAME_RELEASE"   # 4.3 with uname added to
-	exit ;;                             # report: romp-ibm BSD 4.3
+	GUESS=romp-ibm-bsd$UNAME_RELEASE    # 4.3 with uname added to
+	;;                                  # report: romp-ibm BSD 4.3
     *:BOSX:*:*)
-	echo rs6000-bull-bosx
-	exit ;;
+	GUESS=rs6000-bull-bosx
+	;;
     DPX/2?00:B.O.S.:*:*)
-	echo m68k-bull-sysv3
-	exit ;;
+	GUESS=m68k-bull-sysv3
+	;;
     9000/[34]??:4.3bsd:1.*:*)
-	echo m68k-hp-bsd
-	exit ;;
+	GUESS=m68k-hp-bsd
+	;;
     hp300:4.4BSD:*:* | 9000/[34]??:4.3bsd:2.*:*)
-	echo m68k-hp-bsd4.4
-	exit ;;
+	GUESS=m68k-hp-bsd4.4
+	;;
     9000/[34678]??:HP-UX:*:*)
-	HPUX_REV=`echo "$UNAME_RELEASE"|sed -e 's/[^.]*.[0B]*//'`
-	case "$UNAME_MACHINE" in
+	HPUX_REV=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*.[0B]*//'`
+	case $UNAME_MACHINE in
 	    9000/31?)            HP_ARCH=m68000 ;;
 	    9000/[34]??)         HP_ARCH=m68k ;;
 	    9000/[678][0-9][0-9])
-		if [ -x /usr/bin/getconf ]; then
+		if test -x /usr/bin/getconf; then
 		    sc_cpu_version=`/usr/bin/getconf SC_CPU_VERSION 2>/dev/null`
 		    sc_kernel_bits=`/usr/bin/getconf SC_KERNEL_BITS 2>/dev/null`
-		    case "$sc_cpu_version" in
+		    case $sc_cpu_version in
 		      523) HP_ARCH=hppa1.0 ;; # CPU_PA_RISC1_0
 		      528) HP_ARCH=hppa1.1 ;; # CPU_PA_RISC1_1
 		      532)                      # CPU_PA_RISC2_0
-			case "$sc_kernel_bits" in
+			case $sc_kernel_bits in
 			  32) HP_ARCH=hppa2.0n ;;
 			  64) HP_ARCH=hppa2.0w ;;
 			  '') HP_ARCH=hppa2.0 ;;   # HP-UX 10.20
 			esac ;;
 		    esac
 		fi
-		if [ "$HP_ARCH" = "" ]; then
-		    eval "$set_cc_for_build"
+		if test "$HP_ARCH" = ""; then
+		    set_cc_for_build
 		    sed 's/^		//' << EOF > "$dummy.c"
 
 		#define _HPUX_SOURCE
@@ -698,9 +747,9 @@
 		    test -z "$HP_ARCH" && HP_ARCH=hppa
 		fi ;;
 	esac
-	if [ "$HP_ARCH" = hppa2.0w ]
+	if test "$HP_ARCH" = hppa2.0w
 	then
-	    eval "$set_cc_for_build"
+	    set_cc_for_build
 
 	    # hppa2.0w-hp-hpux* has a 64-bit kernel and a compiler generating
 	    # 32-bit code.  hppa64-hp-hpux* has the same kernel and a compiler
@@ -719,14 +768,14 @@
 		HP_ARCH=hppa64
 	    fi
 	fi
-	echo "$HP_ARCH"-hp-hpux"$HPUX_REV"
-	exit ;;
+	GUESS=$HP_ARCH-hp-hpux$HPUX_REV
+	;;
     ia64:HP-UX:*:*)
-	HPUX_REV=`echo "$UNAME_RELEASE"|sed -e 's/[^.]*.[0B]*//'`
-	echo ia64-hp-hpux"$HPUX_REV"
-	exit ;;
+	HPUX_REV=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*.[0B]*//'`
+	GUESS=ia64-hp-hpux$HPUX_REV
+	;;
     3050*:HI-UX:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	sed 's/^	//' << EOF > "$dummy.c"
 	#include <unistd.h>
 	int
@@ -754,36 +803,36 @@
 EOF
 	$CC_FOR_BUILD -o "$dummy" "$dummy.c" && SYSTEM_NAME=`"$dummy"` &&
 		{ echo "$SYSTEM_NAME"; exit; }
-	echo unknown-hitachi-hiuxwe2
-	exit ;;
+	GUESS=unknown-hitachi-hiuxwe2
+	;;
     9000/7??:4.3bsd:*:* | 9000/8?[79]:4.3bsd:*:*)
-	echo hppa1.1-hp-bsd
-	exit ;;
+	GUESS=hppa1.1-hp-bsd
+	;;
     9000/8??:4.3bsd:*:*)
-	echo hppa1.0-hp-bsd
-	exit ;;
+	GUESS=hppa1.0-hp-bsd
+	;;
     *9??*:MPE/iX:*:* | *3000*:MPE/iX:*:*)
-	echo hppa1.0-hp-mpeix
-	exit ;;
+	GUESS=hppa1.0-hp-mpeix
+	;;
     hp7??:OSF1:*:* | hp8?[79]:OSF1:*:*)
-	echo hppa1.1-hp-osf
-	exit ;;
+	GUESS=hppa1.1-hp-osf
+	;;
     hp8??:OSF1:*:*)
-	echo hppa1.0-hp-osf
-	exit ;;
+	GUESS=hppa1.0-hp-osf
+	;;
     i*86:OSF1:*:*)
-	if [ -x /usr/sbin/sysversion ] ; then
-	    echo "$UNAME_MACHINE"-unknown-osf1mk
+	if test -x /usr/sbin/sysversion ; then
+	    GUESS=$UNAME_MACHINE-unknown-osf1mk
 	else
-	    echo "$UNAME_MACHINE"-unknown-osf1
+	    GUESS=$UNAME_MACHINE-unknown-osf1
 	fi
-	exit ;;
+	;;
     parisc*:Lites*:*:*)
-	echo hppa1.1-hp-lites
-	exit ;;
+	GUESS=hppa1.1-hp-lites
+	;;
     C1*:ConvexOS:*:* | convex:ConvexOS:C1*:*)
-	echo c1-convex-bsd
-	exit ;;
+	GUESS=c1-convex-bsd
+	;;
     C2*:ConvexOS:*:* | convex:ConvexOS:C2*:*)
 	if getsysinfo -f scalar_acc
 	then echo c32-convex-bsd
@@ -791,17 +840,18 @@
 	fi
 	exit ;;
     C34*:ConvexOS:*:* | convex:ConvexOS:C34*:*)
-	echo c34-convex-bsd
-	exit ;;
+	GUESS=c34-convex-bsd
+	;;
     C38*:ConvexOS:*:* | convex:ConvexOS:C38*:*)
-	echo c38-convex-bsd
-	exit ;;
+	GUESS=c38-convex-bsd
+	;;
     C4*:ConvexOS:*:* | convex:ConvexOS:C4*:*)
-	echo c4-convex-bsd
-	exit ;;
+	GUESS=c4-convex-bsd
+	;;
     CRAY*Y-MP:*:*:*)
-	echo ymp-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=ymp-cray-unicos$CRAY_REL
+	;;
     CRAY*[A-Z]90:*:*:*)
 	echo "$UNAME_MACHINE"-cray-unicos"$UNAME_RELEASE" \
 	| sed -e 's/CRAY.*\([A-Z]90\)/\1/' \
@@ -809,103 +859,155 @@
 	      -e 's/\.[^.]*$/.X/'
 	exit ;;
     CRAY*TS:*:*:*)
-	echo t90-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=t90-cray-unicos$CRAY_REL
+	;;
     CRAY*T3E:*:*:*)
-	echo alphaev5-cray-unicosmk"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=alphaev5-cray-unicosmk$CRAY_REL
+	;;
     CRAY*SV1:*:*:*)
-	echo sv1-cray-unicos"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=sv1-cray-unicos$CRAY_REL
+	;;
     *:UNICOS/mp:*:*)
-	echo craynv-cray-unicosmp"$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'
-	exit ;;
+	CRAY_REL=`echo "$UNAME_RELEASE" | sed -e 's/\.[^.]*$/.X/'`
+	GUESS=craynv-cray-unicosmp$CRAY_REL
+	;;
     F30[01]:UNIX_System_V:*:* | F700:UNIX_System_V:*:*)
 	FUJITSU_PROC=`uname -m | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz`
 	FUJITSU_SYS=`uname -p | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/\///'`
 	FUJITSU_REL=`echo "$UNAME_RELEASE" | sed -e 's/ /_/'`
-	echo "${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
-	exit ;;
+	GUESS=${FUJITSU_PROC}-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}
+	;;
     5000:UNIX_System_V:4.*:*)
 	FUJITSU_SYS=`uname -p | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/\///'`
 	FUJITSU_REL=`echo "$UNAME_RELEASE" | tr ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz | sed -e 's/ /_/'`
-	echo "sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}"
-	exit ;;
+	GUESS=sparc-fujitsu-${FUJITSU_SYS}${FUJITSU_REL}
+	;;
     i*86:BSD/386:*:* | i*86:BSD/OS:*:* | *:Ascend\ Embedded/OS:*:*)
-	echo "$UNAME_MACHINE"-pc-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-bsdi$UNAME_RELEASE
+	;;
     sparc*:BSD/OS:*:*)
-	echo sparc-unknown-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-unknown-bsdi$UNAME_RELEASE
+	;;
     *:BSD/OS:*:*)
-	echo "$UNAME_MACHINE"-unknown-bsdi"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-bsdi$UNAME_RELEASE
+	;;
+    arm:FreeBSD:*:*)
+	UNAME_PROCESSOR=`uname -p`
+	set_cc_for_build
+	if echo __ARM_PCS_VFP | $CC_FOR_BUILD -E - 2>/dev/null \
+	    | grep -q __ARM_PCS_VFP
+	then
+	    FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	    GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL-gnueabi
+	else
+	    FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	    GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL-gnueabihf
+	fi
+	;;
     *:FreeBSD:*:*)
-	UNAME_PROCESSOR=`/usr/bin/uname -p`
-	case "$UNAME_PROCESSOR" in
+	UNAME_PROCESSOR=`uname -p`
+	case $UNAME_PROCESSOR in
 	    amd64)
 		UNAME_PROCESSOR=x86_64 ;;
 	    i386)
 		UNAME_PROCESSOR=i586 ;;
 	esac
-	echo "$UNAME_PROCESSOR"-unknown-freebsd"`echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`"
-	exit ;;
+	FREEBSD_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_PROCESSOR-unknown-freebsd$FREEBSD_REL
+	;;
     i*:CYGWIN*:*)
-	echo "$UNAME_MACHINE"-pc-cygwin
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-cygwin
+	;;
     *:MINGW64*:*)
-	echo "$UNAME_MACHINE"-pc-mingw64
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-mingw64
+	;;
     *:MINGW*:*)
-	echo "$UNAME_MACHINE"-pc-mingw32
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-mingw32
+	;;
     *:MSYS*:*)
-	echo "$UNAME_MACHINE"-pc-msys
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-msys
+	;;
     i*:PW*:*)
-	echo "$UNAME_MACHINE"-pc-pw32
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-pw32
+	;;
+    *:SerenityOS:*:*)
+        GUESS=$UNAME_MACHINE-pc-serenity
+        ;;
     *:Interix*:*)
-	case "$UNAME_MACHINE" in
+	case $UNAME_MACHINE in
 	    x86)
-		echo i586-pc-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=i586-pc-interix$UNAME_RELEASE
+		;;
 	    authenticamd | genuineintel | EM64T)
-		echo x86_64-unknown-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=x86_64-unknown-interix$UNAME_RELEASE
+		;;
 	    IA64)
-		echo ia64-unknown-interix"$UNAME_RELEASE"
-		exit ;;
+		GUESS=ia64-unknown-interix$UNAME_RELEASE
+		;;
 	esac ;;
     i*:UWIN*:*)
-	echo "$UNAME_MACHINE"-pc-uwin
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-uwin
+	;;
     amd64:CYGWIN*:*:* | x86_64:CYGWIN*:*:*)
-	echo x86_64-unknown-cygwin
-	exit ;;
+	GUESS=x86_64-pc-cygwin
+	;;
     prep*:SunOS:5.*:*)
-	echo powerpcle-unknown-solaris2"`echo "$UNAME_RELEASE"|sed -e 's/[^.]*//'`"
-	exit ;;
+	SUN_REL=`echo "$UNAME_RELEASE" | sed -e 's/[^.]*//'`
+	GUESS=powerpcle-unknown-solaris2$SUN_REL
+	;;
     *:GNU:*:*)
 	# the GNU system
-	echo "`echo "$UNAME_MACHINE"|sed -e 's,[-/].*$,,'`-unknown-$LIBC`echo "$UNAME_RELEASE"|sed -e 's,/.*$,,'`"
-	exit ;;
+	GNU_ARCH=`echo "$UNAME_MACHINE" | sed -e 's,[-/].*$,,'`
+	GNU_REL=`echo "$UNAME_RELEASE" | sed -e 's,/.*$,,'`
+	GUESS=$GNU_ARCH-unknown-$LIBC$GNU_REL
+	;;
     *:GNU/*:*:*)
 	# other systems with GNU libc and userland
-	echo "$UNAME_MACHINE-unknown-`echo "$UNAME_SYSTEM" | sed 's,^[^/]*/,,' | tr "[:upper:]" "[:lower:]"``echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`-$LIBC"
-	exit ;;
-    i*86:Minix:*:*)
-	echo "$UNAME_MACHINE"-pc-minix
-	exit ;;
+	GNU_SYS=`echo "$UNAME_SYSTEM" | sed 's,^[^/]*/,,' | tr "[:upper:]" "[:lower:]"`
+	GNU_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_MACHINE-unknown-$GNU_SYS$GNU_REL-$LIBC
+	;;
+    x86_64:[Mm]anagarm:*:*|i?86:[Mm]anagarm:*:*)
+	GUESS="$UNAME_MACHINE-pc-managarm-mlibc"
+	;;
+    *:[Mm]anagarm:*:*)
+	GUESS="$UNAME_MACHINE-unknown-managarm-mlibc"
+	;;
+    *:Minix:*:*)
+	GUESS=$UNAME_MACHINE-unknown-minix
+	;;
     aarch64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	set_cc_for_build
+	CPU=$UNAME_MACHINE
+	LIBCABI=$LIBC
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
+	    ABI=64
+	    sed 's/^	    //' << EOF > "$dummy.c"
+	    #ifdef __ARM_EABI__
+	    #ifdef __ARM_PCS_VFP
+	    ABI=eabihf
+	    #else
+	    ABI=eabi
+	    #endif
+	    #endif
+EOF
+	    cc_set_abi=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^ABI' | sed 's, ,,g'`
+	    eval "$cc_set_abi"
+	    case $ABI in
+		eabi | eabihf) CPU=armv8l; LIBCABI=$LIBC$ABI ;;
+	    esac
+	fi
+	GUESS=$CPU-unknown-linux-$LIBCABI
+	;;
     aarch64_be:Linux:*:*)
 	UNAME_MACHINE=aarch64_be
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     alpha:Linux:*:*)
-	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' < /proc/cpuinfo` in
+	case `sed -n '/^cpu model/s/^.*: \(.*\)/\1/p' /proc/cpuinfo 2>/dev/null` in
 	  EV5)   UNAME_MACHINE=alphaev5 ;;
 	  EV56)  UNAME_MACHINE=alphaev56 ;;
 	  PCA56) UNAME_MACHINE=alphapca56 ;;
@@ -916,183 +1018,245 @@
 	esac
 	objdump --private-headers /bin/sh | grep -q ld.so.1
 	if test "$?" = 0 ; then LIBC=gnulibc1 ; fi
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
-    arc:Linux:*:* | arceb:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
+    arc:Linux:*:* | arceb:Linux:*:* | arc32:Linux:*:* | arc64:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     arm*:Linux:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
 	if echo __ARM_EABI__ | $CC_FOR_BUILD -E - 2>/dev/null \
 	    | grep -q __ARM_EABI__
 	then
-	    echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
+	    GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
 	else
 	    if echo __ARM_PCS_VFP | $CC_FOR_BUILD -E - 2>/dev/null \
 		| grep -q __ARM_PCS_VFP
 	    then
-		echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"eabi
+		GUESS=$UNAME_MACHINE-unknown-linux-${LIBC}eabi
 	    else
-		echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"eabihf
+		GUESS=$UNAME_MACHINE-unknown-linux-${LIBC}eabihf
 	    fi
 	fi
-	exit ;;
+	;;
     avr32*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     cris:Linux:*:*)
-	echo "$UNAME_MACHINE"-axis-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-axis-linux-$LIBC
+	;;
     crisv32:Linux:*:*)
-	echo "$UNAME_MACHINE"-axis-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-axis-linux-$LIBC
+	;;
     e2k:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     frv:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     hexagon:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     i*86:Linux:*:*)
-	echo "$UNAME_MACHINE"-pc-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-linux-$LIBC
+	;;
     ia64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     k1om:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
+    kvx:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
+    kvx:cos:*:*)
+	GUESS=$UNAME_MACHINE-unknown-cos
+	;;
+    kvx:mbr:*:*)
+	GUESS=$UNAME_MACHINE-unknown-mbr
+	;;
+    loongarch32:Linux:*:* | loongarch64:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     m32r*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     m68*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     mips:Linux:*:* | mips64:Linux:*:*)
-	eval "$set_cc_for_build"
+	set_cc_for_build
+	IS_GLIBC=0
+	test x"${LIBC}" = xgnu && IS_GLIBC=1
 	sed 's/^	//' << EOF > "$dummy.c"
 	#undef CPU
-	#undef ${UNAME_MACHINE}
-	#undef ${UNAME_MACHINE}el
+	#undef mips
+	#undef mipsel
+	#undef mips64
+	#undef mips64el
+	#if ${IS_GLIBC} && defined(_ABI64)
+	LIBCABI=gnuabi64
+	#else
+	#if ${IS_GLIBC} && defined(_ABIN32)
+	LIBCABI=gnuabin32
+	#else
+	LIBCABI=${LIBC}
+	#endif
+	#endif
+
+	#if ${IS_GLIBC} && defined(__mips64) && defined(__mips_isa_rev) && __mips_isa_rev>=6
+	CPU=mipsisa64r6
+	#else
+	#if ${IS_GLIBC} && !defined(__mips64) && defined(__mips_isa_rev) && __mips_isa_rev>=6
+	CPU=mipsisa32r6
+	#else
+	#if defined(__mips64)
+	CPU=mips64
+	#else
+	CPU=mips
+	#endif
+	#endif
+	#endif
+
 	#if defined(__MIPSEL__) || defined(__MIPSEL) || defined(_MIPSEL) || defined(MIPSEL)
-	CPU=${UNAME_MACHINE}el
+	MIPS_ENDIAN=el
 	#else
 	#if defined(__MIPSEB__) || defined(__MIPSEB) || defined(_MIPSEB) || defined(MIPSEB)
-	CPU=${UNAME_MACHINE}
+	MIPS_ENDIAN=
 	#else
-	CPU=
+	MIPS_ENDIAN=
 	#endif
 	#endif
 EOF
-	eval "`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^CPU'`"
-	test "x$CPU" != x && { echo "$CPU-unknown-linux-$LIBC"; exit; }
+	cc_set_vars=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^CPU\|^MIPS_ENDIAN\|^LIBCABI'`
+	eval "$cc_set_vars"
+	test "x$CPU" != x && { echo "$CPU${MIPS_ENDIAN}-unknown-linux-$LIBCABI"; exit; }
 	;;
     mips64el:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     openrisc*:Linux:*:*)
-	echo or1k-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=or1k-unknown-linux-$LIBC
+	;;
     or32:Linux:*:* | or1k*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     padre:Linux:*:*)
-	echo sparc-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=sparc-unknown-linux-$LIBC
+	;;
     parisc64:Linux:*:* | hppa64:Linux:*:*)
-	echo hppa64-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=hppa64-unknown-linux-$LIBC
+	;;
     parisc:Linux:*:* | hppa:Linux:*:*)
 	# Look for CPU level
 	case `grep '^cpu[^a-z]*:' /proc/cpuinfo 2>/dev/null | cut -d' ' -f2` in
-	  PA7*) echo hppa1.1-unknown-linux-"$LIBC" ;;
-	  PA8*) echo hppa2.0-unknown-linux-"$LIBC" ;;
-	  *)    echo hppa-unknown-linux-"$LIBC" ;;
+	  PA7*) GUESS=hppa1.1-unknown-linux-$LIBC ;;
+	  PA8*) GUESS=hppa2.0-unknown-linux-$LIBC ;;
+	  *)    GUESS=hppa-unknown-linux-$LIBC ;;
 	esac
-	exit ;;
+	;;
     ppc64:Linux:*:*)
-	echo powerpc64-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc64-unknown-linux-$LIBC
+	;;
     ppc:Linux:*:*)
-	echo powerpc-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc-unknown-linux-$LIBC
+	;;
     ppc64le:Linux:*:*)
-	echo powerpc64le-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpc64le-unknown-linux-$LIBC
+	;;
     ppcle:Linux:*:*)
-	echo powerpcle-unknown-linux-"$LIBC"
-	exit ;;
-    riscv32:Linux:*:* | riscv64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=powerpcle-unknown-linux-$LIBC
+	;;
+    riscv32:Linux:*:* | riscv32be:Linux:*:* | riscv64:Linux:*:* | riscv64be:Linux:*:*)
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     s390:Linux:*:* | s390x:Linux:*:*)
-	echo "$UNAME_MACHINE"-ibm-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-ibm-linux-$LIBC
+	;;
     sh64*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     sh*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     sparc:Linux:*:* | sparc64:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     tile*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     vax:Linux:*:*)
-	echo "$UNAME_MACHINE"-dec-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-dec-linux-$LIBC
+	;;
     x86_64:Linux:*:*)
-	echo "$UNAME_MACHINE"-pc-linux-"$LIBC"
-	exit ;;
+	set_cc_for_build
+	CPU=$UNAME_MACHINE
+	LIBCABI=$LIBC
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
+	    ABI=64
+	    sed 's/^	    //' << EOF > "$dummy.c"
+	    #ifdef __i386__
+	    ABI=x86
+	    #else
+	    #ifdef __ILP32__
+	    ABI=x32
+	    #endif
+	    #endif
+EOF
+	    cc_set_abi=`$CC_FOR_BUILD -E "$dummy.c" 2>/dev/null | grep '^ABI' | sed 's, ,,g'`
+	    eval "$cc_set_abi"
+	    case $ABI in
+		x86) CPU=i686 ;;
+		x32) LIBCABI=${LIBC}x32 ;;
+	    esac
+	fi
+	GUESS=$CPU-pc-linux-$LIBCABI
+	;;
     xtensa*:Linux:*:*)
-	echo "$UNAME_MACHINE"-unknown-linux-"$LIBC"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-linux-$LIBC
+	;;
     i*86:DYNIX/ptx:4*:*)
 	# ptx 4.0 does uname -s correctly, with DYNIX/ptx in there.
 	# earlier versions are messed up and put the nodename in both
 	# sysname and nodename.
-	echo i386-sequent-sysv4
-	exit ;;
+	GUESS=i386-sequent-sysv4
+	;;
     i*86:UNIX_SV:4.2MP:2.*)
 	# Unixware is an offshoot of SVR4, but it has its own version
 	# number series starting with 2...
 	# I am not positive that other SVR4 systems won't match this,
 	# I just have to hope.  -- rms.
 	# Use sysv4.2uw... so that sysv4* matches it.
-	echo "$UNAME_MACHINE"-pc-sysv4.2uw"$UNAME_VERSION"
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-sysv4.2uw$UNAME_VERSION
+	;;
     i*86:OS/2:*:*)
-	# If we were able to find `uname', then EMX Unix compatibility
+	# If we were able to find 'uname', then EMX Unix compatibility
 	# is probably installed.
-	echo "$UNAME_MACHINE"-pc-os2-emx
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-os2-emx
+	;;
     i*86:XTS-300:*:STOP)
-	echo "$UNAME_MACHINE"-unknown-stop
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-stop
+	;;
     i*86:atheos:*:*)
-	echo "$UNAME_MACHINE"-unknown-atheos
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-atheos
+	;;
     i*86:syllable:*:*)
-	echo "$UNAME_MACHINE"-pc-syllable
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-syllable
+	;;
     i*86:LynxOS:2.*:* | i*86:LynxOS:3.[01]*:* | i*86:LynxOS:4.[02]*:*)
-	echo i386-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=i386-unknown-lynxos$UNAME_RELEASE
+	;;
     i*86:*DOS:*:*)
-	echo "$UNAME_MACHINE"-pc-msdosdjgpp
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-msdosdjgpp
+	;;
     i*86:*:4.*:*)
 	UNAME_REL=`echo "$UNAME_RELEASE" | sed 's/\/MP$//'`
 	if grep Novell /usr/include/link.h >/dev/null 2>/dev/null; then
-		echo "$UNAME_MACHINE"-univel-sysv"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-univel-sysv$UNAME_REL
 	else
-		echo "$UNAME_MACHINE"-pc-sysv"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-sysv$UNAME_REL
 	fi
-	exit ;;
+	;;
     i*86:*:5:[678]*)
 	# UnixWare 7.x, OpenUNIX and OpenServer 6.
 	case `/bin/uname -X | grep "^Machine"` in
@@ -1100,12 +1264,12 @@
 	    *Pentium)	     UNAME_MACHINE=i586 ;;
 	    *Pent*|*Celeron) UNAME_MACHINE=i686 ;;
 	esac
-	echo "$UNAME_MACHINE-unknown-sysv${UNAME_RELEASE}${UNAME_SYSTEM}{$UNAME_VERSION}"
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-sysv${UNAME_RELEASE}${UNAME_SYSTEM}${UNAME_VERSION}
+	;;
     i*86:*:3.2:*)
 	if test -f /usr/options/cb.name; then
 		UNAME_REL=`sed -n 's/.*Version //p' </usr/options/cb.name`
-		echo "$UNAME_MACHINE"-pc-isc"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-isc$UNAME_REL
 	elif /bin/uname -X 2>/dev/null >/dev/null ; then
 		UNAME_REL=`(/bin/uname -X|grep Release|sed -e 's/.*= //')`
 		(/bin/uname -X|grep i80486 >/dev/null) && UNAME_MACHINE=i486
@@ -1115,11 +1279,11 @@
 			&& UNAME_MACHINE=i686
 		(/bin/uname -X|grep '^Machine.*Pentium Pro' >/dev/null) \
 			&& UNAME_MACHINE=i686
-		echo "$UNAME_MACHINE"-pc-sco"$UNAME_REL"
+		GUESS=$UNAME_MACHINE-pc-sco$UNAME_REL
 	else
-		echo "$UNAME_MACHINE"-pc-sysv32
+		GUESS=$UNAME_MACHINE-pc-sysv32
 	fi
-	exit ;;
+	;;
     pc:*:*:*)
 	# Left here for compatibility:
 	# uname -m prints for DJGPP always 'pc', but it prints nothing about
@@ -1127,31 +1291,31 @@
 	# Note: whatever this is, it MUST be the same as what config.sub
 	# prints for the "djgpp" host, or else GDB configure will decide that
 	# this is a cross-build.
-	echo i586-pc-msdosdjgpp
-	exit ;;
+	GUESS=i586-pc-msdosdjgpp
+	;;
     Intel:Mach:3*:*)
-	echo i386-pc-mach3
-	exit ;;
+	GUESS=i386-pc-mach3
+	;;
     paragon:*:*:*)
-	echo i860-intel-osf1
-	exit ;;
+	GUESS=i860-intel-osf1
+	;;
     i860:*:4.*:*) # i860-SVR4
 	if grep Stardent /usr/include/sys/uadmin.h >/dev/null 2>&1 ; then
-	  echo i860-stardent-sysv"$UNAME_RELEASE" # Stardent Vistra i860-SVR4
+	  GUESS=i860-stardent-sysv$UNAME_RELEASE    # Stardent Vistra i860-SVR4
 	else # Add other i860-SVR4 vendors below as they are discovered.
-	  echo i860-unknown-sysv"$UNAME_RELEASE"  # Unknown i860-SVR4
+	  GUESS=i860-unknown-sysv$UNAME_RELEASE     # Unknown i860-SVR4
 	fi
-	exit ;;
+	;;
     mini*:CTIX:SYS*5:*)
 	# "miniframe"
-	echo m68010-convergent-sysv
-	exit ;;
+	GUESS=m68010-convergent-sysv
+	;;
     mc68k:UNIX:SYSTEM5:3.51m)
-	echo m68k-convergent-sysv
-	exit ;;
+	GUESS=m68k-convergent-sysv
+	;;
     M680?0:D-NIX:5.3:*)
-	echo m68k-diab-dnix
-	exit ;;
+	GUESS=m68k-diab-dnix
+	;;
     M68*:*:R3V[5678]*:*)
 	test -r /sysV68 && { echo 'm68k-motorola-sysv'; exit; } ;;
     3[345]??:*:4.0:3.0 | 3[34]??A:*:4.0:3.0 | 3[34]??,*:*:4.0:3.0 | 3[34]??/*:*:4.0:3.0 | 4400:*:4.0:3.0 | 4850:*:4.0:3.0 | SKA40:*:4.0:3.0 | SDS2:*:4.0:3.0 | SHG2:*:4.0:3.0 | S7501*:*:4.0:3.0)
@@ -1176,249 +1340,407 @@
 	/bin/uname -p 2>/dev/null | /bin/grep pteron >/dev/null \
 	    && { echo i586-ncr-sysv4.3"$OS_REL"; exit; } ;;
     m68*:LynxOS:2.*:* | m68*:LynxOS:3.0*:*)
-	echo m68k-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-unknown-lynxos$UNAME_RELEASE
+	;;
     mc68030:UNIX_System_V:4.*:*)
-	echo m68k-atari-sysv4
-	exit ;;
+	GUESS=m68k-atari-sysv4
+	;;
     TSUNAMI:LynxOS:2.*:*)
-	echo sparc-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sparc-unknown-lynxos$UNAME_RELEASE
+	;;
     rs6000:LynxOS:2.*:*)
-	echo rs6000-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=rs6000-unknown-lynxos$UNAME_RELEASE
+	;;
     PowerPC:LynxOS:2.*:* | PowerPC:LynxOS:3.[01]*:* | PowerPC:LynxOS:4.[02]*:*)
-	echo powerpc-unknown-lynxos"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-unknown-lynxos$UNAME_RELEASE
+	;;
     SM[BE]S:UNIX_SV:*:*)
-	echo mips-dde-sysv"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-dde-sysv$UNAME_RELEASE
+	;;
     RM*:ReliantUNIX-*:*:*)
-	echo mips-sni-sysv4
-	exit ;;
+	GUESS=mips-sni-sysv4
+	;;
     RM*:SINIX-*:*:*)
-	echo mips-sni-sysv4
-	exit ;;
+	GUESS=mips-sni-sysv4
+	;;
     *:SINIX-*:*:*)
 	if uname -p 2>/dev/null >/dev/null ; then
 		UNAME_MACHINE=`(uname -p) 2>/dev/null`
-		echo "$UNAME_MACHINE"-sni-sysv4
+		GUESS=$UNAME_MACHINE-sni-sysv4
 	else
-		echo ns32k-sni-sysv
+		GUESS=ns32k-sni-sysv
 	fi
-	exit ;;
-    PENTIUM:*:4.0*:*)	# Unisys `ClearPath HMP IX 4000' SVR4/MP effort
+	;;
+    PENTIUM:*:4.0*:*)	# Unisys 'ClearPath HMP IX 4000' SVR4/MP effort
 			# says <Richard.M.Bartel@ccMail.Census.GOV>
-	echo i586-unisys-sysv4
-	exit ;;
+	GUESS=i586-unisys-sysv4
+	;;
     *:UNIX_System_V:4*:FTX*)
 	# From Gerald Hewes <hewes@openmarket.com>.
 	# How about differentiating between stratus architectures? -djm
-	echo hppa1.1-stratus-sysv4
-	exit ;;
+	GUESS=hppa1.1-stratus-sysv4
+	;;
     *:*:*:FTX*)
 	# From seanf@swdc.stratus.com.
-	echo i860-stratus-sysv4
-	exit ;;
+	GUESS=i860-stratus-sysv4
+	;;
     i*86:VOS:*:*)
 	# From Paul.Green@stratus.com.
-	echo "$UNAME_MACHINE"-stratus-vos
-	exit ;;
+	GUESS=$UNAME_MACHINE-stratus-vos
+	;;
     *:VOS:*:*)
 	# From Paul.Green@stratus.com.
-	echo hppa1.1-stratus-vos
-	exit ;;
+	GUESS=hppa1.1-stratus-vos
+	;;
     mc68*:A/UX:*:*)
-	echo m68k-apple-aux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=m68k-apple-aux$UNAME_RELEASE
+	;;
     news*:NEWS-OS:6*:*)
-	echo mips-sony-newsos6
-	exit ;;
+	GUESS=mips-sony-newsos6
+	;;
     R[34]000:*System_V*:*:* | R4000:UNIX_SYSV:*:* | R*000:UNIX_SV:*:*)
-	if [ -d /usr/nec ]; then
-		echo mips-nec-sysv"$UNAME_RELEASE"
+	if test -d /usr/nec; then
+		GUESS=mips-nec-sysv$UNAME_RELEASE
 	else
-		echo mips-unknown-sysv"$UNAME_RELEASE"
+		GUESS=mips-unknown-sysv$UNAME_RELEASE
 	fi
-	exit ;;
+	;;
     BeBox:BeOS:*:*)	# BeOS running on hardware made by Be, PPC only.
-	echo powerpc-be-beos
-	exit ;;
+	GUESS=powerpc-be-beos
+	;;
     BeMac:BeOS:*:*)	# BeOS running on Mac or Mac clone, PPC only.
-	echo powerpc-apple-beos
-	exit ;;
+	GUESS=powerpc-apple-beos
+	;;
     BePC:BeOS:*:*)	# BeOS running on Intel PC compatible.
-	echo i586-pc-beos
-	exit ;;
+	GUESS=i586-pc-beos
+	;;
     BePC:Haiku:*:*)	# Haiku running on Intel PC compatible.
-	echo i586-pc-haiku
-	exit ;;
-    x86_64:Haiku:*:*)
-	echo x86_64-unknown-haiku
-	exit ;;
+	GUESS=i586-pc-haiku
+	;;
+    ppc:Haiku:*:*)	# Haiku running on Apple PowerPC
+	GUESS=powerpc-apple-haiku
+	;;
+    *:Haiku:*:*)	# Haiku modern gcc (not bound by BeOS compat)
+	GUESS=$UNAME_MACHINE-unknown-haiku
+	;;
     SX-4:SUPER-UX:*:*)
-	echo sx4-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx4-nec-superux$UNAME_RELEASE
+	;;
     SX-5:SUPER-UX:*:*)
-	echo sx5-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx5-nec-superux$UNAME_RELEASE
+	;;
     SX-6:SUPER-UX:*:*)
-	echo sx6-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx6-nec-superux$UNAME_RELEASE
+	;;
     SX-7:SUPER-UX:*:*)
-	echo sx7-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx7-nec-superux$UNAME_RELEASE
+	;;
     SX-8:SUPER-UX:*:*)
-	echo sx8-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx8-nec-superux$UNAME_RELEASE
+	;;
     SX-8R:SUPER-UX:*:*)
-	echo sx8r-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sx8r-nec-superux$UNAME_RELEASE
+	;;
     SX-ACE:SUPER-UX:*:*)
-	echo sxace-nec-superux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=sxace-nec-superux$UNAME_RELEASE
+	;;
     Power*:Rhapsody:*:*)
-	echo powerpc-apple-rhapsody"$UNAME_RELEASE"
-	exit ;;
+	GUESS=powerpc-apple-rhapsody$UNAME_RELEASE
+	;;
     *:Rhapsody:*:*)
-	echo "$UNAME_MACHINE"-apple-rhapsody"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-apple-rhapsody$UNAME_RELEASE
+	;;
+    arm64:Darwin:*:*)
+	GUESS=aarch64-apple-darwin$UNAME_RELEASE
+	;;
     *:Darwin:*:*)
-	UNAME_PROCESSOR=`uname -p` || UNAME_PROCESSOR=unknown
-	eval "$set_cc_for_build"
-	if test "$UNAME_PROCESSOR" = unknown ; then
-	    UNAME_PROCESSOR=powerpc
+	UNAME_PROCESSOR=`uname -p`
+	case $UNAME_PROCESSOR in
+	    unknown) UNAME_PROCESSOR=powerpc ;;
+	esac
+	if command -v xcode-select > /dev/null 2> /dev/null && \
+		! xcode-select --print-path > /dev/null 2> /dev/null ; then
+	    # Avoid executing cc if there is no toolchain installed as
+	    # cc will be a stub that puts up a graphical alert
+	    # prompting the user to install developer tools.
+	    CC_FOR_BUILD=no_compiler_found
+	else
+	    set_cc_for_build
 	fi
-	if test "`echo "$UNAME_RELEASE" | sed -e 's/\..*//'`" -le 10 ; then
-	    if [ "$CC_FOR_BUILD" != no_compiler_found ]; then
-		if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
-		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
-		       grep IS_64BIT_ARCH >/dev/null
-		then
-		    case $UNAME_PROCESSOR in
-			i386) UNAME_PROCESSOR=x86_64 ;;
-			powerpc) UNAME_PROCESSOR=powerpc64 ;;
-		    esac
-		fi
-		# On 10.4-10.6 one might compile for PowerPC via gcc -arch ppc
-		if (echo '#ifdef __POWERPC__'; echo IS_PPC; echo '#endif') | \
-		       (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
-		       grep IS_PPC >/dev/null
-		then
-		    UNAME_PROCESSOR=powerpc
-		fi
+	if test "$CC_FOR_BUILD" != no_compiler_found; then
+	    if (echo '#ifdef __LP64__'; echo IS_64BIT_ARCH; echo '#endif') | \
+		   (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		   grep IS_64BIT_ARCH >/dev/null
+	    then
+		case $UNAME_PROCESSOR in
+		    i386) UNAME_PROCESSOR=x86_64 ;;
+		    powerpc) UNAME_PROCESSOR=powerpc64 ;;
+		esac
+	    fi
+	    # On 10.4-10.6 one might compile for PowerPC via gcc -arch ppc
+	    if (echo '#ifdef __POWERPC__'; echo IS_PPC; echo '#endif') | \
+		   (CCOPTS="" $CC_FOR_BUILD -E - 2>/dev/null) | \
+		   grep IS_PPC >/dev/null
+	    then
+		UNAME_PROCESSOR=powerpc
 	    fi
 	elif test "$UNAME_PROCESSOR" = i386 ; then
-	    # Avoid executing cc on OS X 10.9, as it ships with a stub
-	    # that puts up a graphical alert prompting to install
-	    # developer tools.  Any system running Mac OS X 10.7 or
-	    # later (Darwin 11 and later) is required to have a 64-bit
-	    # processor. This is not true of the ARM version of Darwin
-	    # that Apple uses in portable devices.
-	    UNAME_PROCESSOR=x86_64
+	    # uname -m returns i386 or x86_64
+	    UNAME_PROCESSOR=$UNAME_MACHINE
 	fi
-	echo "$UNAME_PROCESSOR"-apple-darwin"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_PROCESSOR-apple-darwin$UNAME_RELEASE
+	;;
     *:procnto*:*:* | *:QNX:[0123456789]*:*)
 	UNAME_PROCESSOR=`uname -p`
 	if test "$UNAME_PROCESSOR" = x86; then
 		UNAME_PROCESSOR=i386
 		UNAME_MACHINE=pc
 	fi
-	echo "$UNAME_PROCESSOR"-"$UNAME_MACHINE"-nto-qnx"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_PROCESSOR-$UNAME_MACHINE-nto-qnx$UNAME_RELEASE
+	;;
     *:QNX:*:4*)
-	echo i386-pc-qnx
-	exit ;;
+	GUESS=i386-pc-qnx
+	;;
     NEO-*:NONSTOP_KERNEL:*:*)
-	echo neo-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=neo-tandem-nsk$UNAME_RELEASE
+	;;
     NSE-*:NONSTOP_KERNEL:*:*)
-	echo nse-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nse-tandem-nsk$UNAME_RELEASE
+	;;
     NSR-*:NONSTOP_KERNEL:*:*)
-	echo nsr-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsr-tandem-nsk$UNAME_RELEASE
+	;;
     NSV-*:NONSTOP_KERNEL:*:*)
-	echo nsv-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsv-tandem-nsk$UNAME_RELEASE
+	;;
     NSX-*:NONSTOP_KERNEL:*:*)
-	echo nsx-tandem-nsk"$UNAME_RELEASE"
-	exit ;;
+	GUESS=nsx-tandem-nsk$UNAME_RELEASE
+	;;
     *:NonStop-UX:*:*)
-	echo mips-compaq-nonstopux
-	exit ;;
+	GUESS=mips-compaq-nonstopux
+	;;
     BS2000:POSIX*:*:*)
-	echo bs2000-siemens-sysv
-	exit ;;
+	GUESS=bs2000-siemens-sysv
+	;;
     DS/*:UNIX_System_V:*:*)
-	echo "$UNAME_MACHINE"-"$UNAME_SYSTEM"-"$UNAME_RELEASE"
-	exit ;;
+	GUESS=$UNAME_MACHINE-$UNAME_SYSTEM-$UNAME_RELEASE
+	;;
     *:Plan9:*:*)
 	# "uname -m" is not consistent, so use $cputype instead. 386
 	# is converted to i386 for consistency with other x86
 	# operating systems.
-	if test "$cputype" = 386; then
+	if test "${cputype-}" = 386; then
 	    UNAME_MACHINE=i386
-	else
-	    UNAME_MACHINE="$cputype"
+	elif test "x${cputype-}" != x; then
+	    UNAME_MACHINE=$cputype
 	fi
-	echo "$UNAME_MACHINE"-unknown-plan9
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-plan9
+	;;
     *:TOPS-10:*:*)
-	echo pdp10-unknown-tops10
-	exit ;;
+	GUESS=pdp10-unknown-tops10
+	;;
     *:TENEX:*:*)
-	echo pdp10-unknown-tenex
-	exit ;;
+	GUESS=pdp10-unknown-tenex
+	;;
     KS10:TOPS-20:*:* | KL10:TOPS-20:*:* | TYPE4:TOPS-20:*:*)
-	echo pdp10-dec-tops20
-	exit ;;
+	GUESS=pdp10-dec-tops20
+	;;
     XKL-1:TOPS-20:*:* | TYPE5:TOPS-20:*:*)
-	echo pdp10-xkl-tops20
-	exit ;;
+	GUESS=pdp10-xkl-tops20
+	;;
     *:TOPS-20:*:*)
-	echo pdp10-unknown-tops20
-	exit ;;
+	GUESS=pdp10-unknown-tops20
+	;;
     *:ITS:*:*)
-	echo pdp10-unknown-its
-	exit ;;
+	GUESS=pdp10-unknown-its
+	;;
     SEI:*:*:SEIUX)
-	echo mips-sei-seiux"$UNAME_RELEASE"
-	exit ;;
+	GUESS=mips-sei-seiux$UNAME_RELEASE
+	;;
     *:DragonFly:*:*)
-	echo "$UNAME_MACHINE"-unknown-dragonfly"`echo "$UNAME_RELEASE"|sed -e 's/[-(].*//'`"
-	exit ;;
+	DRAGONFLY_REL=`echo "$UNAME_RELEASE" | sed -e 's/[-(].*//'`
+	GUESS=$UNAME_MACHINE-unknown-dragonfly$DRAGONFLY_REL
+	;;
     *:*VMS:*:*)
 	UNAME_MACHINE=`(uname -p) 2>/dev/null`
-	case "$UNAME_MACHINE" in
-	    A*) echo alpha-dec-vms ; exit ;;
-	    I*) echo ia64-dec-vms ; exit ;;
-	    V*) echo vax-dec-vms ; exit ;;
+	case $UNAME_MACHINE in
+	    A*) GUESS=alpha-dec-vms ;;
+	    I*) GUESS=ia64-dec-vms ;;
+	    V*) GUESS=vax-dec-vms ;;
 	esac ;;
     *:XENIX:*:SysV)
-	echo i386-pc-xenix
-	exit ;;
+	GUESS=i386-pc-xenix
+	;;
     i*86:skyos:*:*)
-	echo "$UNAME_MACHINE"-pc-skyos"`echo "$UNAME_RELEASE" | sed -e 's/ .*$//'`"
-	exit ;;
+	SKYOS_REL=`echo "$UNAME_RELEASE" | sed -e 's/ .*$//'`
+	GUESS=$UNAME_MACHINE-pc-skyos$SKYOS_REL
+	;;
     i*86:rdos:*:*)
-	echo "$UNAME_MACHINE"-pc-rdos
-	exit ;;
-    i*86:AROS:*:*)
-	echo "$UNAME_MACHINE"-pc-aros
-	exit ;;
+	GUESS=$UNAME_MACHINE-pc-rdos
+	;;
+    i*86:Fiwix:*:*)
+	GUESS=$UNAME_MACHINE-pc-fiwix
+	;;
+    *:AROS:*:*)
+	GUESS=$UNAME_MACHINE-unknown-aros
+	;;
     x86_64:VMkernel:*:*)
-	echo "$UNAME_MACHINE"-unknown-esx
-	exit ;;
+	GUESS=$UNAME_MACHINE-unknown-esx
+	;;
     amd64:Isilon\ OneFS:*:*)
-	echo x86_64-unknown-onefs
-	exit ;;
+	GUESS=x86_64-unknown-onefs
+	;;
+    *:Unleashed:*:*)
+	GUESS=$UNAME_MACHINE-unknown-unleashed$UNAME_RELEASE
+	;;
 esac
 
+# Do we have a guess based on uname results?
+if test "x$GUESS" != x; then
+    echo "$GUESS"
+    exit
+fi
+
+# No uname command or uname output not recognized.
+set_cc_for_build
+cat > "$dummy.c" <<EOF
+#ifdef _SEQUENT_
+#include <sys/types.h>
+#include <sys/utsname.h>
+#endif
+#if defined(ultrix) || defined(_ultrix) || defined(__ultrix) || defined(__ultrix__)
+#if defined (vax) || defined (__vax) || defined (__vax__) || defined(mips) || defined(__mips) || defined(__mips__) || defined(MIPS) || defined(__MIPS__)
+#include <signal.h>
+#if defined(_SIZE_T_) || defined(SIGLOST)
+#include <sys/utsname.h>
+#endif
+#endif
+#endif
+main ()
+{
+#if defined (sony)
+#if defined (MIPSEB)
+  /* BFD wants "bsd" instead of "newsos".  Perhaps BFD should be changed,
+     I don't know....  */
+  printf ("mips-sony-bsd\n"); exit (0);
+#else
+#include <sys/param.h>
+  printf ("m68k-sony-newsos%s\n",
+#ifdef NEWSOS4
+  "4"
+#else
+  ""
+#endif
+  ); exit (0);
+#endif
+#endif
+
+#if defined (NeXT)
+#if !defined (__ARCHITECTURE__)
+#define __ARCHITECTURE__ "m68k"
+#endif
+  int version;
+  version=`(hostinfo | sed -n 's/.*NeXT Mach \([0-9]*\).*/\1/p') 2>/dev/null`;
+  if (version < 4)
+    printf ("%s-next-nextstep%d\n", __ARCHITECTURE__, version);
+  else
+    printf ("%s-next-openstep%d\n", __ARCHITECTURE__, version);
+  exit (0);
+#endif
+
+#if defined (MULTIMAX) || defined (n16)
+#if defined (UMAXV)
+  printf ("ns32k-encore-sysv\n"); exit (0);
+#else
+#if defined (CMU)
+  printf ("ns32k-encore-mach\n"); exit (0);
+#else
+  printf ("ns32k-encore-bsd\n"); exit (0);
+#endif
+#endif
+#endif
+
+#if defined (__386BSD__)
+  printf ("i386-pc-bsd\n"); exit (0);
+#endif
+
+#if defined (sequent)
+#if defined (i386)
+  printf ("i386-sequent-dynix\n"); exit (0);
+#endif
+#if defined (ns32000)
+  printf ("ns32k-sequent-dynix\n"); exit (0);
+#endif
+#endif
+
+#if defined (_SEQUENT_)
+  struct utsname un;
+
+  uname(&un);
+  if (strncmp(un.version, "V2", 2) == 0) {
+    printf ("i386-sequent-ptx2\n"); exit (0);
+  }
+  if (strncmp(un.version, "V1", 2) == 0) { /* XXX is V1 correct? */
+    printf ("i386-sequent-ptx1\n"); exit (0);
+  }
+  printf ("i386-sequent-ptx\n"); exit (0);
+#endif
+
+#if defined (vax)
+#if !defined (ultrix)
+#include <sys/param.h>
+#if defined (BSD)
+#if BSD == 43
+  printf ("vax-dec-bsd4.3\n"); exit (0);
+#else
+#if BSD == 199006
+  printf ("vax-dec-bsd4.3reno\n"); exit (0);
+#else
+  printf ("vax-dec-bsd\n"); exit (0);
+#endif
+#endif
+#else
+  printf ("vax-dec-bsd\n"); exit (0);
+#endif
+#else
+#if defined(_SIZE_T_) || defined(SIGLOST)
+  struct utsname un;
+  uname (&un);
+  printf ("vax-dec-ultrix%s\n", un.release); exit (0);
+#else
+  printf ("vax-dec-ultrix\n"); exit (0);
+#endif
+#endif
+#endif
+#if defined(ultrix) || defined(_ultrix) || defined(__ultrix) || defined(__ultrix__)
+#if defined(mips) || defined(__mips) || defined(__mips__) || defined(MIPS) || defined(__MIPS__)
+#if defined(_SIZE_T_) || defined(SIGLOST)
+  struct utsname *un;
+  uname (&un);
+  printf ("mips-dec-ultrix%s\n", un.release); exit (0);
+#else
+  printf ("mips-dec-ultrix\n"); exit (0);
+#endif
+#endif
+#endif
+
+#if defined (alliant) && defined (i860)
+  printf ("i860-alliant-bsd\n"); exit (0);
+#endif
+
+  exit (1);
+}
+EOF
+
+$CC_FOR_BUILD -o "$dummy" "$dummy.c" 2>/dev/null && SYSTEM_NAME=`"$dummy"` &&
+	{ echo "$SYSTEM_NAME"; exit; }
+
+# Apollos put the system type in the environment.
+test -d /usr/apollo && { echo "$ISP-apollo-$SYSTYPE"; exit; }
+
 echo "$0: unable to guess system type" >&2
 
-case "$UNAME_MACHINE:$UNAME_SYSTEM" in
+case $UNAME_MACHINE:$UNAME_SYSTEM in
     mips:Linux | mips64:Linux)
 	# If we got here on MIPS GNU/Linux, output extra information.
 	cat >&2 <<EOF
@@ -1435,9 +1757,17 @@
 operating system you are using. If your script is old, overwrite *all*
 copies of config.guess and config.sub with the latest versions from:
 
-  https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.guess
+  https://git.savannah.gnu.org/cgit/config.git/plain/config.guess
 and
-  https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub
+  https://git.savannah.gnu.org/cgit/config.git/plain/config.sub
+EOF
+
+our_year=`echo $timestamp | sed 's,-.*,,'`
+thisyear=`date +%Y`
+# shellcheck disable=SC2003
+script_age=`expr "$thisyear" - "$our_year"`
+if test "$script_age" -lt 3 ; then
+   cat >&2 <<EOF
 
 If $0 has already been updated, send the following data and any
 information you think might be pertinent to config-patches@gnu.org to
@@ -1465,6 +1795,7 @@
 UNAME_SYSTEM  = "$UNAME_SYSTEM"
 UNAME_VERSION = "$UNAME_VERSION"
 EOF
+fi
 
 exit 1
 
diff --git a/config.h.in b/config.h.in
index 2931048..3ec0c8a 100644
--- a/config.h.in
+++ b/config.h.in
@@ -3,27 +3,27 @@
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H
 
-/* Define to 1 if you have the `feenableexcept' function. */
+/* Define to 1 if you have the 'feenableexcept' function. */
 #undef HAVE_FEENABLEEXCEPT
 
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
-/* Define to 1 if you have the `m' library (-lm). */
+/* Define to 1 if you have the 'm' library (-lm). */
 #undef HAVE_LIBM
 
-/* Define to 1 if you have the `z' library (-lz). */
+/* Define to 1 if you have the 'z' library (-lz). */
 #undef HAVE_LIBZ
 
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
-/* Define to 1 if you have the `pow' function. */
+/* Define to 1 if you have the 'pow' function. */
 #undef HAVE_POW
 
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
+/* Define to 1 if you have the <stdio.h> header file. */
+#undef HAVE_STDIO_H
+
 /* Define to 1 if you have the <stdlib.h> header file. */
 #undef HAVE_STDLIB_H
 
@@ -78,6 +78,18 @@
 /* Enable Intel SSE optimizations */
 #undef PNG_INTEL_SSE_OPT
 
+/* Enable LOONGARCH LSX optimizations */
+#undef PNG_LOONGARCH_LSX_OPT
+
+/* Turn on MIPS MMI optimizations at run-time */
+#undef PNG_MIPS_MMI_API_SUPPORTED
+
+/* Check for MIPS MMI support at run-time */
+#undef PNG_MIPS_MMI_CHECK_SUPPORTED
+
+/* Enable MIPS MMI optimizations */
+#undef PNG_MIPS_MMI_OPT
+
 /* Turn on MIPS MSA optimizations at run-time */
 #undef PNG_MIPS_MSA_API_SUPPORTED
 
@@ -96,31 +108,28 @@
 /* Enable POWERPC VSX optimizations */
 #undef PNG_POWERPC_VSX_OPT
 
-/* Define to 1 if you have the ANSI C header files. */
+/* Define to 1 if all of the C89 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
 #undef STDC_HEADERS
 
-/* Define to 1 if your <sys/time.h> declares `struct tm'. */
+/* Define to 1 if your <sys/time.h> declares 'struct tm'. */
 #undef TM_IN_SYS_TIME
 
 /* Version number of package */
 #undef VERSION
 
-/* Define to empty if `const' does not conform to ANSI C. */
-#undef const
-
 /* Define to the equivalent of the C99 'restrict' keyword, or to
    nothing if this is not supported.  Do not define if restrict is
-   supported directly.  */
+   supported only directly.  */
 #undef restrict
-/* Work around a bug in Sun C++: it does not support _Restrict or
-   __restrict__, even though the corresponding Sun C compiler ends up with
-   "#define restrict _Restrict" or "#define restrict __restrict__" in the
-   previous line.  Perhaps some future version of Sun C++ will work with
-   restrict; if so, hopefully it defines __RESTRICT like Sun C does.  */
-#if defined __SUNPRO_CC && !defined __RESTRICT
+/* Work around a bug in older versions of Sun C++, which did not
+   #define __restrict__ or support _Restrict or __restrict__
+   even though the corresponding Sun C compiler ended up with
+   "#define restrict _Restrict" or "#define restrict __restrict__"
+   in the previous line.  This workaround can be removed once
+   we assume Oracle Developer Studio 12.5 (2016) or later.  */
+#if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__
 # define _Restrict
 # define __restrict__
 #endif
-
-/* Define to `unsigned int' if <sys/types.h> does not define. */
-#undef size_t
diff --git a/config.sub b/config.sub
index 9ccf09a..defe52c 100755
--- a/config.sub
+++ b/config.sub
@@ -1,12 +1,14 @@
 #! /bin/sh
 # Configuration validation subroutine script.
-#   Copyright 1992-2018 Free Software Foundation, Inc.
+#   Copyright 1992-2023 Free Software Foundation, Inc.
 
-timestamp='2018-03-08'
+# shellcheck disable=SC2006,SC2268 # see below for rationale
+
+timestamp='2023-09-19'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
+# the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful, but
@@ -33,7 +35,7 @@
 # Otherwise, we print the canonical config type on stdout and succeed.
 
 # You can get the latest version of this script from:
-# https://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=config.sub
+# https://git.savannah.gnu.org/cgit/config.git/plain/config.sub
 
 # This file is supposed to be the same for all GNU packages
 # and recognize all the CPU types, system types and aliases
@@ -50,6 +52,13 @@
 #	CPU_TYPE-MANUFACTURER-KERNEL-OPERATING_SYSTEM
 # It is wrong to echo any other type of specification.
 
+# The "shellcheck disable" line above the timestamp inhibits complaints
+# about features and limitations of the classic Bourne shell that were
+# superseded or lifted in POSIX.  However, this script identifies a wide
+# variety of pre-POSIX systems that do not have POSIX shells at all, and
+# even some reasonably current systems (Solaris 10 as case-in-point) still
+# have a pre-POSIX /bin/sh.
+
 me=`echo "$0" | sed -e 's,.*/,,'`
 
 usage="\
@@ -67,13 +76,13 @@
 version="\
 GNU config.sub ($timestamp)
 
-Copyright 1992-2018 Free Software Foundation, Inc.
+Copyright 1992-2023 Free Software Foundation, Inc.
 
 This is free software; see the source for copying conditions.  There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
 
 help="
-Try \`$me --help' for more information."
+Try '$me --help' for more information."
 
 # Parse command line
 while test $# -gt 0 ; do
@@ -89,7 +98,7 @@
     - )	# Use stdin as input.
        break ;;
     -* )
-       echo "$me: invalid option $1$help"
+       echo "$me: invalid option $1$help" >&2
        exit 1 ;;
 
     *local*)
@@ -110,1223 +119,1165 @@
     exit 1;;
 esac
 
-# Separate what the user gave into CPU-COMPANY and OS or KERNEL-OS (if any).
-# Here we must recognize all the valid KERNEL-OS combinations.
-maybe_os=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`
-case $maybe_os in
-  nto-qnx* | linux-gnu* | linux-android* | linux-dietlibc | linux-newlib* | \
-  linux-musl* | linux-uclibc* | uclinux-uclibc* | uclinux-gnu* | kfreebsd*-gnu* | \
-  knetbsd*-gnu* | netbsd*-gnu* | netbsd*-eabi* | \
-  kopensolaris*-gnu* | cloudabi*-eabi* | \
-  storm-chaos* | os2-emx* | rtmk-nova*)
-    os=-$maybe_os
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`
-    ;;
-  android-linux)
-    os=-linux-android
-    basic_machine=`echo "$1" | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`-unknown
-    ;;
-  *)
-    basic_machine=`echo "$1" | sed 's/-[^-]*$//'`
-    if [ "$basic_machine" != "$1" ]
-    then os=`echo "$1" | sed 's/.*-/-/'`
-    else os=; fi
-    ;;
-esac
+# Split fields of configuration type
+# shellcheck disable=SC2162
+saved_IFS=$IFS
+IFS="-" read field1 field2 field3 field4 <<EOF
+$1
+EOF
+IFS=$saved_IFS
 
-### Let's recognize common machines as not being operating systems so
-### that things like config.sub decstation-3100 work.  We also
-### recognize some manufacturers as not being operating systems, so we
-### can provide default operating systems below.
-case $os in
-	-sun*os*)
-		# Prevent following clause from handling this invalid input.
-		;;
-	-dec* | -mips* | -sequent* | -encore* | -pc532* | -sgi* | -sony* | \
-	-att* | -7300* | -3300* | -delta* | -motorola* | -sun[234]* | \
-	-unicom* | -ibm* | -next | -hp | -isi* | -apollo | -altos* | \
-	-convergent* | -ncr* | -news | -32* | -3600* | -3100* | -hitachi* |\
-	-c[123]* | -convex* | -sun | -crds | -omron* | -dg | -ultra | -tti* | \
-	-harris | -dolphin | -highlevel | -gould | -cbm | -ns | -masscomp | \
-	-apple | -axis | -knuth | -cray | -microblaze*)
-		os=
-		basic_machine=$1
-		;;
-	-bluegene*)
-		os=-cnk
-		;;
-	-sim | -cisco | -oki | -wec | -winbond)
-		os=
-		basic_machine=$1
-		;;
-	-scout)
-		;;
-	-wrs)
-		os=-vxworks
-		basic_machine=$1
-		;;
-	-chorusos*)
-		os=-chorusos
-		basic_machine=$1
-		;;
-	-chorusrdb)
-		os=-chorusrdb
-		basic_machine=$1
-		;;
-	-hiux*)
-		os=-hiuxwe2
-		;;
-	-sco6)
-		os=-sco5v6
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco5)
-		os=-sco3.2v5
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco4)
-		os=-sco3.2v4
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco3.2.[4-9]*)
-		os=`echo $os | sed -e 's/sco3.2./sco3.2v/'`
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco3.2v[4-9]*)
-		# Don't forget version if it is 3.2v4 or newer.
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco5v6*)
-		# Don't forget version if it is 3.2v4 or newer.
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-sco*)
-		os=-sco3.2v2
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-udk*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-isc)
-		os=-isc2.2
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-clix*)
-		basic_machine=clipper-intergraph
-		;;
-	-isc*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-pc/'`
-		;;
-	-lynx*178)
-		os=-lynxos178
-		;;
-	-lynx*5)
-		os=-lynxos5
-		;;
-	-lynx*)
-		os=-lynxos
-		;;
-	-ptx*)
-		basic_machine=`echo "$1" | sed -e 's/86-.*/86-sequent/'`
-		;;
-	-psos*)
-		os=-psos
-		;;
-	-mint | -mint[0-9]*)
-		basic_machine=m68k-atari
-		os=-mint
-		;;
-esac
-
-# Decode aliases for certain CPU-COMPANY combinations.
-case $basic_machine in
-	# Recognize the basic CPU types without company name.
-	# Some are omitted here because they have special meanings below.
-	1750a | 580 \
-	| a29k \
-	| aarch64 | aarch64_be \
-	| alpha | alphaev[4-8] | alphaev56 | alphaev6[78] | alphapca5[67] \
-	| alpha64 | alpha64ev[4-8] | alpha64ev56 | alpha64ev6[78] | alpha64pca5[67] \
-	| am33_2.0 \
-	| arc | arceb \
-	| arm | arm[bl]e | arme[lb] | armv[2-8] | armv[3-8][lb] | armv7[arm] \
-	| avr | avr32 \
-	| ba \
-	| be32 | be64 \
-	| bfin \
-	| c4x | c8051 | clipper \
-	| d10v | d30v | dlx | dsp16xx \
-	| e2k | epiphany \
-	| fido | fr30 | frv | ft32 \
-	| h8300 | h8500 | hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
-	| hexagon \
-	| i370 | i860 | i960 | ia16 | ia64 \
-	| ip2k | iq2000 \
-	| k1om \
-	| le32 | le64 \
-	| lm32 \
-	| m32c | m32r | m32rle | m68000 | m68k | m88k \
-	| maxq | mb | microblaze | microblazeel | mcore | mep | metag \
-	| mips | mipsbe | mipseb | mipsel | mipsle \
-	| mips16 \
-	| mips64 | mips64el \
-	| mips64octeon | mips64octeonel \
-	| mips64orion | mips64orionel \
-	| mips64r5900 | mips64r5900el \
-	| mips64vr | mips64vrel \
-	| mips64vr4100 | mips64vr4100el \
-	| mips64vr4300 | mips64vr4300el \
-	| mips64vr5000 | mips64vr5000el \
-	| mips64vr5900 | mips64vr5900el \
-	| mipsisa32 | mipsisa32el \
-	| mipsisa32r2 | mipsisa32r2el \
-	| mipsisa32r6 | mipsisa32r6el \
-	| mipsisa64 | mipsisa64el \
-	| mipsisa64r2 | mipsisa64r2el \
-	| mipsisa64r6 | mipsisa64r6el \
-	| mipsisa64sb1 | mipsisa64sb1el \
-	| mipsisa64sr71k | mipsisa64sr71kel \
-	| mipsr5900 | mipsr5900el \
-	| mipstx39 | mipstx39el \
-	| mn10200 | mn10300 \
-	| moxie \
-	| mt \
-	| msp430 \
-	| nds32 | nds32le | nds32be \
-	| nios | nios2 | nios2eb | nios2el \
-	| ns16k | ns32k \
-	| open8 | or1k | or1knd | or32 \
-	| pdp10 | pj | pjl \
-	| powerpc | powerpc64 | powerpc64le | powerpcle \
-	| pru \
-	| pyramid \
-	| riscv32 | riscv64 \
-	| rl78 | rx \
-	| score \
-	| sh | sh[1234] | sh[24]a | sh[24]aeb | sh[23]e | sh[234]eb | sheb | shbe | shle | sh[1234]le | sh3ele \
-	| sh64 | sh64le \
-	| sparc | sparc64 | sparc64b | sparc64v | sparc86x | sparclet | sparclite \
-	| sparcv8 | sparcv9 | sparcv9b | sparcv9v \
-	| spu \
-	| tahoe | tic4x | tic54x | tic55x | tic6x | tic80 | tron \
-	| ubicom32 \
-	| v850 | v850e | v850e1 | v850e2 | v850es | v850e2v3 \
-	| visium \
-	| wasm32 \
-	| x86 | xc16x | xstormy16 | xtensa \
-	| z8k | z80)
-		basic_machine=$basic_machine-unknown
-		;;
-	c54x)
-		basic_machine=tic54x-unknown
-		;;
-	c55x)
-		basic_machine=tic55x-unknown
-		;;
-	c6x)
-		basic_machine=tic6x-unknown
-		;;
-	leon|leon[3-9])
-		basic_machine=sparc-$basic_machine
-		;;
-	m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x | nvptx | picochip)
-		basic_machine=$basic_machine-unknown
-		os=-none
-		;;
-	m88110 | m680[12346]0 | m683?2 | m68360 | m5200 | v70 | w65)
-		;;
-	ms1)
-		basic_machine=mt-unknown
-		;;
-
-	strongarm | thumb | xscale)
-		basic_machine=arm-unknown
-		;;
-	xgate)
-		basic_machine=$basic_machine-unknown
-		os=-none
-		;;
-	xscaleeb)
-		basic_machine=armeb-unknown
-		;;
-
-	xscaleel)
-		basic_machine=armel-unknown
-		;;
-
-	# We use `pc' rather than `unknown'
-	# because (1) that's what they normally are, and
-	# (2) the word "unknown" tends to confuse beginning users.
-	i*86 | x86_64)
-	  basic_machine=$basic_machine-pc
-	  ;;
-	# Object if more than one company name word.
-	*-*-*)
-		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
+# Separate into logical components for further validation
+case $1 in
+	*-*-*-*-*)
+		echo "Invalid configuration '$1': more than four components" >&2
 		exit 1
 		;;
-	# Recognize the basic CPU types with company name.
-	580-* \
-	| a29k-* \
-	| aarch64-* | aarch64_be-* \
-	| alpha-* | alphaev[4-8]-* | alphaev56-* | alphaev6[78]-* \
-	| alpha64-* | alpha64ev[4-8]-* | alpha64ev56-* | alpha64ev6[78]-* \
-	| alphapca5[67]-* | alpha64pca5[67]-* | arc-* | arceb-* \
-	| arm-*  | armbe-* | armle-* | armeb-* | armv*-* \
-	| avr-* | avr32-* \
-	| ba-* \
-	| be32-* | be64-* \
-	| bfin-* | bs2000-* \
-	| c[123]* | c30-* | [cjt]90-* | c4x-* \
-	| c8051-* | clipper-* | craynv-* | cydra-* \
-	| d10v-* | d30v-* | dlx-* \
-	| e2k-* | elxsi-* \
-	| f30[01]-* | f700-* | fido-* | fr30-* | frv-* | fx80-* \
-	| h8300-* | h8500-* \
-	| hppa-* | hppa1.[01]-* | hppa2.0-* | hppa2.0[nw]-* | hppa64-* \
-	| hexagon-* \
-	| i*86-* | i860-* | i960-* | ia16-* | ia64-* \
-	| ip2k-* | iq2000-* \
-	| k1om-* \
-	| le32-* | le64-* \
-	| lm32-* \
-	| m32c-* | m32r-* | m32rle-* \
-	| m68000-* | m680[012346]0-* | m68360-* | m683?2-* | m68k-* \
-	| m88110-* | m88k-* | maxq-* | mcore-* | metag-* \
-	| microblaze-* | microblazeel-* \
-	| mips-* | mipsbe-* | mipseb-* | mipsel-* | mipsle-* \
-	| mips16-* \
-	| mips64-* | mips64el-* \
-	| mips64octeon-* | mips64octeonel-* \
-	| mips64orion-* | mips64orionel-* \
-	| mips64r5900-* | mips64r5900el-* \
-	| mips64vr-* | mips64vrel-* \
-	| mips64vr4100-* | mips64vr4100el-* \
-	| mips64vr4300-* | mips64vr4300el-* \
-	| mips64vr5000-* | mips64vr5000el-* \
-	| mips64vr5900-* | mips64vr5900el-* \
-	| mipsisa32-* | mipsisa32el-* \
-	| mipsisa32r2-* | mipsisa32r2el-* \
-	| mipsisa32r6-* | mipsisa32r6el-* \
-	| mipsisa64-* | mipsisa64el-* \
-	| mipsisa64r2-* | mipsisa64r2el-* \
-	| mipsisa64r6-* | mipsisa64r6el-* \
-	| mipsisa64sb1-* | mipsisa64sb1el-* \
-	| mipsisa64sr71k-* | mipsisa64sr71kel-* \
-	| mipsr5900-* | mipsr5900el-* \
-	| mipstx39-* | mipstx39el-* \
-	| mmix-* \
-	| mt-* \
-	| msp430-* \
-	| nds32-* | nds32le-* | nds32be-* \
-	| nios-* | nios2-* | nios2eb-* | nios2el-* \
-	| none-* | np1-* | ns16k-* | ns32k-* \
-	| open8-* \
-	| or1k*-* \
-	| orion-* \
-	| pdp10-* | pdp11-* | pj-* | pjl-* | pn-* | power-* \
-	| powerpc-* | powerpc64-* | powerpc64le-* | powerpcle-* \
-	| pru-* \
-	| pyramid-* \
-	| riscv32-* | riscv64-* \
-	| rl78-* | romp-* | rs6000-* | rx-* \
-	| sh-* | sh[1234]-* | sh[24]a-* | sh[24]aeb-* | sh[23]e-* | sh[34]eb-* | sheb-* | shbe-* \
-	| shle-* | sh[1234]le-* | sh3ele-* | sh64-* | sh64le-* \
-	| sparc-* | sparc64-* | sparc64b-* | sparc64v-* | sparc86x-* | sparclet-* \
-	| sparclite-* \
-	| sparcv8-* | sparcv9-* | sparcv9b-* | sparcv9v-* | sv1-* | sx*-* \
-	| tahoe-* \
-	| tic30-* | tic4x-* | tic54x-* | tic55x-* | tic6x-* | tic80-* \
-	| tile*-* \
-	| tron-* \
-	| ubicom32-* \
-	| v850-* | v850e-* | v850e1-* | v850es-* | v850e2-* | v850e2v3-* \
-	| vax-* \
-	| visium-* \
-	| wasm32-* \
-	| we32k-* \
-	| x86-* | x86_64-* | xc16x-* | xps100-* \
-	| xstormy16-* | xtensa*-* \
-	| ymp-* \
-	| z8k-* | z80-*)
+	*-*-*-*)
+		basic_machine=$field1-$field2
+		basic_os=$field3-$field4
 		;;
-	# Recognize the basic CPU types without company name, with glob match.
-	xtensa*)
-		basic_machine=$basic_machine-unknown
+	*-*-*)
+		# Ambiguous whether COMPANY is present, or skipped and KERNEL-OS is two
+		# parts
+		maybe_os=$field2-$field3
+		case $maybe_os in
+			nto-qnx* | linux-* | uclinux-uclibc* \
+			| uclinux-gnu* | kfreebsd*-gnu* | knetbsd*-gnu* | netbsd*-gnu* \
+			| netbsd*-eabi* | kopensolaris*-gnu* | cloudabi*-eabi* \
+			| storm-chaos* | os2-emx* | rtmk-nova* | managarm-* \
+			| windows-* )
+				basic_machine=$field1
+				basic_os=$maybe_os
+				;;
+			android-linux)
+				basic_machine=$field1-unknown
+				basic_os=linux-android
+				;;
+			*)
+				basic_machine=$field1-$field2
+				basic_os=$field3
+				;;
+		esac
 		;;
+	*-*)
+		# A lone config we happen to match not fitting any pattern
+		case $field1-$field2 in
+			decstation-3100)
+				basic_machine=mips-dec
+				basic_os=
+				;;
+			*-*)
+				# Second component is usually, but not always the OS
+				case $field2 in
+					# Prevent following clause from handling this valid os
+					sun*os*)
+						basic_machine=$field1
+						basic_os=$field2
+						;;
+					zephyr*)
+						basic_machine=$field1-unknown
+						basic_os=$field2
+						;;
+					# Manufacturers
+					dec* | mips* | sequent* | encore* | pc533* | sgi* | sony* \
+					| att* | 7300* | 3300* | delta* | motorola* | sun[234]* \
+					| unicom* | ibm* | next | hp | isi* | apollo | altos* \
+					| convergent* | ncr* | news | 32* | 3600* | 3100* \
+					| hitachi* | c[123]* | convex* | sun | crds | omron* | dg \
+					| ultra | tti* | harris | dolphin | highlevel | gould \
+					| cbm | ns | masscomp | apple | axis | knuth | cray \
+					| microblaze* | sim | cisco \
+					| oki | wec | wrs | winbond)
+						basic_machine=$field1-$field2
+						basic_os=
+						;;
+					*)
+						basic_machine=$field1
+						basic_os=$field2
+						;;
+				esac
+			;;
+		esac
+		;;
+	*)
+		# Convert single-component short-hands not valid as part of
+		# multi-component configurations.
+		case $field1 in
+			386bsd)
+				basic_machine=i386-pc
+				basic_os=bsd
+				;;
+			a29khif)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			adobe68k)
+				basic_machine=m68010-adobe
+				basic_os=scout
+				;;
+			alliant)
+				basic_machine=fx80-alliant
+				basic_os=
+				;;
+			altos | altos3068)
+				basic_machine=m68k-altos
+				basic_os=
+				;;
+			am29k)
+				basic_machine=a29k-none
+				basic_os=bsd
+				;;
+			amdahl)
+				basic_machine=580-amdahl
+				basic_os=sysv
+				;;
+			amiga)
+				basic_machine=m68k-unknown
+				basic_os=
+				;;
+			amigaos | amigados)
+				basic_machine=m68k-unknown
+				basic_os=amigaos
+				;;
+			amigaunix | amix)
+				basic_machine=m68k-unknown
+				basic_os=sysv4
+				;;
+			apollo68)
+				basic_machine=m68k-apollo
+				basic_os=sysv
+				;;
+			apollo68bsd)
+				basic_machine=m68k-apollo
+				basic_os=bsd
+				;;
+			aros)
+				basic_machine=i386-pc
+				basic_os=aros
+				;;
+			aux)
+				basic_machine=m68k-apple
+				basic_os=aux
+				;;
+			balance)
+				basic_machine=ns32k-sequent
+				basic_os=dynix
+				;;
+			blackfin)
+				basic_machine=bfin-unknown
+				basic_os=linux
+				;;
+			cegcc)
+				basic_machine=arm-unknown
+				basic_os=cegcc
+				;;
+			convex-c1)
+				basic_machine=c1-convex
+				basic_os=bsd
+				;;
+			convex-c2)
+				basic_machine=c2-convex
+				basic_os=bsd
+				;;
+			convex-c32)
+				basic_machine=c32-convex
+				basic_os=bsd
+				;;
+			convex-c34)
+				basic_machine=c34-convex
+				basic_os=bsd
+				;;
+			convex-c38)
+				basic_machine=c38-convex
+				basic_os=bsd
+				;;
+			cray)
+				basic_machine=j90-cray
+				basic_os=unicos
+				;;
+			crds | unos)
+				basic_machine=m68k-crds
+				basic_os=
+				;;
+			da30)
+				basic_machine=m68k-da30
+				basic_os=
+				;;
+			decstation | pmax | pmin | dec3100 | decstatn)
+				basic_machine=mips-dec
+				basic_os=
+				;;
+			delta88)
+				basic_machine=m88k-motorola
+				basic_os=sysv3
+				;;
+			dicos)
+				basic_machine=i686-pc
+				basic_os=dicos
+				;;
+			djgpp)
+				basic_machine=i586-pc
+				basic_os=msdosdjgpp
+				;;
+			ebmon29k)
+				basic_machine=a29k-amd
+				basic_os=ebmon
+				;;
+			es1800 | OSE68k | ose68k | ose | OSE)
+				basic_machine=m68k-ericsson
+				basic_os=ose
+				;;
+			gmicro)
+				basic_machine=tron-gmicro
+				basic_os=sysv
+				;;
+			go32)
+				basic_machine=i386-pc
+				basic_os=go32
+				;;
+			h8300hms)
+				basic_machine=h8300-hitachi
+				basic_os=hms
+				;;
+			h8300xray)
+				basic_machine=h8300-hitachi
+				basic_os=xray
+				;;
+			h8500hms)
+				basic_machine=h8500-hitachi
+				basic_os=hms
+				;;
+			harris)
+				basic_machine=m88k-harris
+				basic_os=sysv3
+				;;
+			hp300 | hp300hpux)
+				basic_machine=m68k-hp
+				basic_os=hpux
+				;;
+			hp300bsd)
+				basic_machine=m68k-hp
+				basic_os=bsd
+				;;
+			hppaosf)
+				basic_machine=hppa1.1-hp
+				basic_os=osf
+				;;
+			hppro)
+				basic_machine=hppa1.1-hp
+				basic_os=proelf
+				;;
+			i386mach)
+				basic_machine=i386-mach
+				basic_os=mach
+				;;
+			isi68 | isi)
+				basic_machine=m68k-isi
+				basic_os=sysv
+				;;
+			m68knommu)
+				basic_machine=m68k-unknown
+				basic_os=linux
+				;;
+			magnum | m3230)
+				basic_machine=mips-mips
+				basic_os=sysv
+				;;
+			merlin)
+				basic_machine=ns32k-utek
+				basic_os=sysv
+				;;
+			mingw64)
+				basic_machine=x86_64-pc
+				basic_os=mingw64
+				;;
+			mingw32)
+				basic_machine=i686-pc
+				basic_os=mingw32
+				;;
+			mingw32ce)
+				basic_machine=arm-unknown
+				basic_os=mingw32ce
+				;;
+			monitor)
+				basic_machine=m68k-rom68k
+				basic_os=coff
+				;;
+			morphos)
+				basic_machine=powerpc-unknown
+				basic_os=morphos
+				;;
+			moxiebox)
+				basic_machine=moxie-unknown
+				basic_os=moxiebox
+				;;
+			msdos)
+				basic_machine=i386-pc
+				basic_os=msdos
+				;;
+			msys)
+				basic_machine=i686-pc
+				basic_os=msys
+				;;
+			mvs)
+				basic_machine=i370-ibm
+				basic_os=mvs
+				;;
+			nacl)
+				basic_machine=le32-unknown
+				basic_os=nacl
+				;;
+			ncr3000)
+				basic_machine=i486-ncr
+				basic_os=sysv4
+				;;
+			netbsd386)
+				basic_machine=i386-pc
+				basic_os=netbsd
+				;;
+			netwinder)
+				basic_machine=armv4l-rebel
+				basic_os=linux
+				;;
+			news | news700 | news800 | news900)
+				basic_machine=m68k-sony
+				basic_os=newsos
+				;;
+			news1000)
+				basic_machine=m68030-sony
+				basic_os=newsos
+				;;
+			necv70)
+				basic_machine=v70-nec
+				basic_os=sysv
+				;;
+			nh3000)
+				basic_machine=m68k-harris
+				basic_os=cxux
+				;;
+			nh[45]000)
+				basic_machine=m88k-harris
+				basic_os=cxux
+				;;
+			nindy960)
+				basic_machine=i960-intel
+				basic_os=nindy
+				;;
+			mon960)
+				basic_machine=i960-intel
+				basic_os=mon960
+				;;
+			nonstopux)
+				basic_machine=mips-compaq
+				basic_os=nonstopux
+				;;
+			os400)
+				basic_machine=powerpc-ibm
+				basic_os=os400
+				;;
+			OSE68000 | ose68000)
+				basic_machine=m68000-ericsson
+				basic_os=ose
+				;;
+			os68k)
+				basic_machine=m68k-none
+				basic_os=os68k
+				;;
+			paragon)
+				basic_machine=i860-intel
+				basic_os=osf
+				;;
+			parisc)
+				basic_machine=hppa-unknown
+				basic_os=linux
+				;;
+			psp)
+				basic_machine=mipsallegrexel-sony
+				basic_os=psp
+				;;
+			pw32)
+				basic_machine=i586-unknown
+				basic_os=pw32
+				;;
+			rdos | rdos64)
+				basic_machine=x86_64-pc
+				basic_os=rdos
+				;;
+			rdos32)
+				basic_machine=i386-pc
+				basic_os=rdos
+				;;
+			rom68k)
+				basic_machine=m68k-rom68k
+				basic_os=coff
+				;;
+			sa29200)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			sei)
+				basic_machine=mips-sei
+				basic_os=seiux
+				;;
+			sequent)
+				basic_machine=i386-sequent
+				basic_os=
+				;;
+			sps7)
+				basic_machine=m68k-bull
+				basic_os=sysv2
+				;;
+			st2000)
+				basic_machine=m68k-tandem
+				basic_os=
+				;;
+			stratus)
+				basic_machine=i860-stratus
+				basic_os=sysv4
+				;;
+			sun2)
+				basic_machine=m68000-sun
+				basic_os=
+				;;
+			sun2os3)
+				basic_machine=m68000-sun
+				basic_os=sunos3
+				;;
+			sun2os4)
+				basic_machine=m68000-sun
+				basic_os=sunos4
+				;;
+			sun3)
+				basic_machine=m68k-sun
+				basic_os=
+				;;
+			sun3os3)
+				basic_machine=m68k-sun
+				basic_os=sunos3
+				;;
+			sun3os4)
+				basic_machine=m68k-sun
+				basic_os=sunos4
+				;;
+			sun4)
+				basic_machine=sparc-sun
+				basic_os=
+				;;
+			sun4os3)
+				basic_machine=sparc-sun
+				basic_os=sunos3
+				;;
+			sun4os4)
+				basic_machine=sparc-sun
+				basic_os=sunos4
+				;;
+			sun4sol2)
+				basic_machine=sparc-sun
+				basic_os=solaris2
+				;;
+			sun386 | sun386i | roadrunner)
+				basic_machine=i386-sun
+				basic_os=
+				;;
+			sv1)
+				basic_machine=sv1-cray
+				basic_os=unicos
+				;;
+			symmetry)
+				basic_machine=i386-sequent
+				basic_os=dynix
+				;;
+			t3e)
+				basic_machine=alphaev5-cray
+				basic_os=unicos
+				;;
+			t90)
+				basic_machine=t90-cray
+				basic_os=unicos
+				;;
+			toad1)
+				basic_machine=pdp10-xkl
+				basic_os=tops20
+				;;
+			tpf)
+				basic_machine=s390x-ibm
+				basic_os=tpf
+				;;
+			udi29k)
+				basic_machine=a29k-amd
+				basic_os=udi
+				;;
+			ultra3)
+				basic_machine=a29k-nyu
+				basic_os=sym1
+				;;
+			v810 | necv810)
+				basic_machine=v810-nec
+				basic_os=none
+				;;
+			vaxv)
+				basic_machine=vax-dec
+				basic_os=sysv
+				;;
+			vms)
+				basic_machine=vax-dec
+				basic_os=vms
+				;;
+			vsta)
+				basic_machine=i386-pc
+				basic_os=vsta
+				;;
+			vxworks960)
+				basic_machine=i960-wrs
+				basic_os=vxworks
+				;;
+			vxworks68)
+				basic_machine=m68k-wrs
+				basic_os=vxworks
+				;;
+			vxworks29k)
+				basic_machine=a29k-wrs
+				basic_os=vxworks
+				;;
+			xbox)
+				basic_machine=i686-pc
+				basic_os=mingw32
+				;;
+			ymp)
+				basic_machine=ymp-cray
+				basic_os=unicos
+				;;
+			*)
+				basic_machine=$1
+				basic_os=
+				;;
+		esac
+		;;
+esac
+
+# Decode 1-component or ad-hoc basic machines
+case $basic_machine in
+	# Here we handle the default manufacturer of certain CPU types.  It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	w89k)
+		cpu=hppa1.1
+		vendor=winbond
+		;;
+	op50n)
+		cpu=hppa1.1
+		vendor=oki
+		;;
+	op60c)
+		cpu=hppa1.1
+		vendor=oki
+		;;
+	ibm*)
+		cpu=i370
+		vendor=ibm
+		;;
+	orion105)
+		cpu=clipper
+		vendor=highlevel
+		;;
+	mac | mpw | mac-mpw)
+		cpu=m68k
+		vendor=apple
+		;;
+	pmac | pmac-mpw)
+		cpu=powerpc
+		vendor=apple
+		;;
+
 	# Recognize the various machine names and aliases which stand
 	# for a CPU type and a company and sometimes even an OS.
-	386bsd)
-		basic_machine=i386-pc
-		os=-bsd
-		;;
 	3b1 | 7300 | 7300-att | att-7300 | pc7300 | safari | unixpc)
-		basic_machine=m68000-att
+		cpu=m68000
+		vendor=att
 		;;
 	3b*)
-		basic_machine=we32k-att
-		;;
-	a29khif)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	abacus)
-		basic_machine=abacus-unknown
-		;;
-	adobe68k)
-		basic_machine=m68010-adobe
-		os=-scout
-		;;
-	alliant | fx80)
-		basic_machine=fx80-alliant
-		;;
-	altos | altos3068)
-		basic_machine=m68k-altos
-		;;
-	am29k)
-		basic_machine=a29k-none
-		os=-bsd
-		;;
-	amd64)
-		basic_machine=x86_64-pc
-		;;
-	amd64-*)
-		basic_machine=x86_64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	amdahl)
-		basic_machine=580-amdahl
-		os=-sysv
-		;;
-	amiga | amiga-*)
-		basic_machine=m68k-unknown
-		;;
-	amigaos | amigados)
-		basic_machine=m68k-unknown
-		os=-amigaos
-		;;
-	amigaunix | amix)
-		basic_machine=m68k-unknown
-		os=-sysv4
-		;;
-	apollo68)
-		basic_machine=m68k-apollo
-		os=-sysv
-		;;
-	apollo68bsd)
-		basic_machine=m68k-apollo
-		os=-bsd
-		;;
-	aros)
-		basic_machine=i386-pc
-		os=-aros
-		;;
-	asmjs)
-		basic_machine=asmjs-unknown
-		;;
-	aux)
-		basic_machine=m68k-apple
-		os=-aux
-		;;
-	balance)
-		basic_machine=ns32k-sequent
-		os=-dynix
-		;;
-	blackfin)
-		basic_machine=bfin-unknown
-		os=-linux
-		;;
-	blackfin-*)
-		basic_machine=bfin-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
+		cpu=we32k
+		vendor=att
 		;;
 	bluegene*)
-		basic_machine=powerpc-ibm
-		os=-cnk
-		;;
-	c54x-*)
-		basic_machine=tic54x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c55x-*)
-		basic_machine=tic55x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c6x-*)
-		basic_machine=tic6x-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	c90)
-		basic_machine=c90-cray
-		os=-unicos
-		;;
-	cegcc)
-		basic_machine=arm-unknown
-		os=-cegcc
-		;;
-	convex-c1)
-		basic_machine=c1-convex
-		os=-bsd
-		;;
-	convex-c2)
-		basic_machine=c2-convex
-		os=-bsd
-		;;
-	convex-c32)
-		basic_machine=c32-convex
-		os=-bsd
-		;;
-	convex-c34)
-		basic_machine=c34-convex
-		os=-bsd
-		;;
-	convex-c38)
-		basic_machine=c38-convex
-		os=-bsd
-		;;
-	cray | j90)
-		basic_machine=j90-cray
-		os=-unicos
-		;;
-	craynv)
-		basic_machine=craynv-cray
-		os=-unicosmp
-		;;
-	cr16 | cr16-*)
-		basic_machine=cr16-unknown
-		os=-elf
-		;;
-	crds | unos)
-		basic_machine=m68k-crds
-		;;
-	crisv32 | crisv32-* | etraxfs*)
-		basic_machine=crisv32-axis
-		;;
-	cris | cris-* | etrax*)
-		basic_machine=cris-axis
-		;;
-	crx)
-		basic_machine=crx-unknown
-		os=-elf
-		;;
-	da30 | da30-*)
-		basic_machine=m68k-da30
-		;;
-	decstation | decstation-3100 | pmax | pmax-* | pmin | dec3100 | decstatn)
-		basic_machine=mips-dec
+		cpu=powerpc
+		vendor=ibm
+		basic_os=cnk
 		;;
 	decsystem10* | dec10*)
-		basic_machine=pdp10-dec
-		os=-tops10
+		cpu=pdp10
+		vendor=dec
+		basic_os=tops10
 		;;
 	decsystem20* | dec20*)
-		basic_machine=pdp10-dec
-		os=-tops20
+		cpu=pdp10
+		vendor=dec
+		basic_os=tops20
 		;;
 	delta | 3300 | motorola-3300 | motorola-delta \
 	      | 3300-motorola | delta-motorola)
-		basic_machine=m68k-motorola
-		;;
-	delta88)
-		basic_machine=m88k-motorola
-		os=-sysv3
-		;;
-	dicos)
-		basic_machine=i686-pc
-		os=-dicos
-		;;
-	djgpp)
-		basic_machine=i586-pc
-		os=-msdosdjgpp
-		;;
-	dpx20 | dpx20-*)
-		basic_machine=rs6000-bull
-		os=-bosx
+		cpu=m68k
+		vendor=motorola
 		;;
 	dpx2*)
-		basic_machine=m68k-bull
-		os=-sysv3
-		;;
-	e500v[12])
-		basic_machine=powerpc-unknown
-		os=$os"spe"
-		;;
-	e500v[12]-*)
-		basic_machine=powerpc-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=$os"spe"
-		;;
-	ebmon29k)
-		basic_machine=a29k-amd
-		os=-ebmon
-		;;
-	elxsi)
-		basic_machine=elxsi-elxsi
-		os=-bsd
+		cpu=m68k
+		vendor=bull
+		basic_os=sysv3
 		;;
 	encore | umax | mmax)
-		basic_machine=ns32k-encore
+		cpu=ns32k
+		vendor=encore
 		;;
-	es1800 | OSE68k | ose68k | ose | OSE)
-		basic_machine=m68k-ericsson
-		os=-ose
+	elxsi)
+		cpu=elxsi
+		vendor=elxsi
+		basic_os=${basic_os:-bsd}
 		;;
 	fx2800)
-		basic_machine=i860-alliant
+		cpu=i860
+		vendor=alliant
 		;;
 	genix)
-		basic_machine=ns32k-ns
-		;;
-	gmicro)
-		basic_machine=tron-gmicro
-		os=-sysv
-		;;
-	go32)
-		basic_machine=i386-pc
-		os=-go32
+		cpu=ns32k
+		vendor=ns
 		;;
 	h3050r* | hiux*)
-		basic_machine=hppa1.1-hitachi
-		os=-hiuxwe2
-		;;
-	h8300hms)
-		basic_machine=h8300-hitachi
-		os=-hms
-		;;
-	h8300xray)
-		basic_machine=h8300-hitachi
-		os=-xray
-		;;
-	h8500hms)
-		basic_machine=h8500-hitachi
-		os=-hms
-		;;
-	harris)
-		basic_machine=m88k-harris
-		os=-sysv3
-		;;
-	hp300-*)
-		basic_machine=m68k-hp
-		;;
-	hp300bsd)
-		basic_machine=m68k-hp
-		os=-bsd
-		;;
-	hp300hpux)
-		basic_machine=m68k-hp
-		os=-hpux
+		cpu=hppa1.1
+		vendor=hitachi
+		basic_os=hiuxwe2
 		;;
 	hp3k9[0-9][0-9] | hp9[0-9][0-9])
-		basic_machine=hppa1.0-hp
+		cpu=hppa1.0
+		vendor=hp
 		;;
 	hp9k2[0-9][0-9] | hp9k31[0-9])
-		basic_machine=m68000-hp
+		cpu=m68000
+		vendor=hp
 		;;
 	hp9k3[2-9][0-9])
-		basic_machine=m68k-hp
+		cpu=m68k
+		vendor=hp
 		;;
 	hp9k6[0-9][0-9] | hp6[0-9][0-9])
-		basic_machine=hppa1.0-hp
+		cpu=hppa1.0
+		vendor=hp
 		;;
 	hp9k7[0-79][0-9] | hp7[0-79][0-9])
-		basic_machine=hppa1.1-hp
+		cpu=hppa1.1
+		vendor=hp
 		;;
 	hp9k78[0-9] | hp78[0-9])
 		# FIXME: really hppa2.0-hp
-		basic_machine=hppa1.1-hp
+		cpu=hppa1.1
+		vendor=hp
 		;;
 	hp9k8[67]1 | hp8[67]1 | hp9k80[24] | hp80[24] | hp9k8[78]9 | hp8[78]9 | hp9k893 | hp893)
 		# FIXME: really hppa2.0-hp
-		basic_machine=hppa1.1-hp
+		cpu=hppa1.1
+		vendor=hp
 		;;
 	hp9k8[0-9][13679] | hp8[0-9][13679])
-		basic_machine=hppa1.1-hp
+		cpu=hppa1.1
+		vendor=hp
 		;;
 	hp9k8[0-9][0-9] | hp8[0-9][0-9])
-		basic_machine=hppa1.0-hp
-		;;
-	hppaosf)
-		basic_machine=hppa1.1-hp
-		os=-osf
-		;;
-	hppro)
-		basic_machine=hppa1.1-hp
-		os=-proelf
-		;;
-	i370-ibm* | ibm*)
-		basic_machine=i370-ibm
+		cpu=hppa1.0
+		vendor=hp
 		;;
 	i*86v32)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv32
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv32
 		;;
 	i*86v4*)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv4
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv4
 		;;
 	i*86v)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-sysv
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=sysv
 		;;
 	i*86sol2)
-		basic_machine=`echo "$1" | sed -e 's/86.*/86-pc/'`
-		os=-solaris2
+		cpu=`echo "$1" | sed -e 's/86.*/86/'`
+		vendor=pc
+		basic_os=solaris2
 		;;
-	i386mach)
-		basic_machine=i386-mach
-		os=-mach
-		;;
-	vsta)
-		basic_machine=i386-unknown
-		os=-vsta
+	j90 | j90-cray)
+		cpu=j90
+		vendor=cray
+		basic_os=${basic_os:-unicos}
 		;;
 	iris | iris4d)
-		basic_machine=mips-sgi
-		case $os in
-		    -irix*)
+		cpu=mips
+		vendor=sgi
+		case $basic_os in
+		    irix*)
 			;;
 		    *)
-			os=-irix4
+			basic_os=irix4
 			;;
 		esac
 		;;
-	isi68 | isi)
-		basic_machine=m68k-isi
-		os=-sysv
-		;;
-	leon-*|leon[3-9]-*)
-		basic_machine=sparc-`echo "$basic_machine" | sed 's/-.*//'`
-		;;
-	m68knommu)
-		basic_machine=m68k-unknown
-		os=-linux
-		;;
-	m68knommu-*)
-		basic_machine=m68k-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
-		;;
-	magnum | m3230)
-		basic_machine=mips-mips
-		os=-sysv
-		;;
-	merlin)
-		basic_machine=ns32k-utek
-		os=-sysv
-		;;
-	microblaze*)
-		basic_machine=microblaze-xilinx
-		;;
-	mingw64)
-		basic_machine=x86_64-pc
-		os=-mingw64
-		;;
-	mingw32)
-		basic_machine=i686-pc
-		os=-mingw32
-		;;
-	mingw32ce)
-		basic_machine=arm-unknown
-		os=-mingw32ce
-		;;
 	miniframe)
-		basic_machine=m68000-convergent
+		cpu=m68000
+		vendor=convergent
 		;;
-	*mint | -mint[0-9]* | *MiNT | *MiNT[0-9]*)
-		basic_machine=m68k-atari
-		os=-mint
-		;;
-	mips3*-*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/mips3/mips64/'`
-		;;
-	mips3*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/mips3/mips64/'`-unknown
-		;;
-	monitor)
-		basic_machine=m68k-rom68k
-		os=-coff
-		;;
-	morphos)
-		basic_machine=powerpc-unknown
-		os=-morphos
-		;;
-	moxiebox)
-		basic_machine=moxie-unknown
-		os=-moxiebox
-		;;
-	msdos)
-		basic_machine=i386-pc
-		os=-msdos
-		;;
-	ms1-*)
-		basic_machine=`echo "$basic_machine" | sed -e 's/ms1-/mt-/'`
-		;;
-	msys)
-		basic_machine=i686-pc
-		os=-msys
-		;;
-	mvs)
-		basic_machine=i370-ibm
-		os=-mvs
-		;;
-	nacl)
-		basic_machine=le32-unknown
-		os=-nacl
-		;;
-	ncr3000)
-		basic_machine=i486-ncr
-		os=-sysv4
-		;;
-	netbsd386)
-		basic_machine=i386-unknown
-		os=-netbsd
-		;;
-	netwinder)
-		basic_machine=armv4l-rebel
-		os=-linux
-		;;
-	news | news700 | news800 | news900)
-		basic_machine=m68k-sony
-		os=-newsos
-		;;
-	news1000)
-		basic_machine=m68030-sony
-		os=-newsos
+	*mint | mint[0-9]* | *MiNT | *MiNT[0-9]*)
+		cpu=m68k
+		vendor=atari
+		basic_os=mint
 		;;
 	news-3600 | risc-news)
-		basic_machine=mips-sony
-		os=-newsos
-		;;
-	necv70)
-		basic_machine=v70-nec
-		os=-sysv
+		cpu=mips
+		vendor=sony
+		basic_os=newsos
 		;;
 	next | m*-next)
-		basic_machine=m68k-next
-		case $os in
-		    -nextstep* )
+		cpu=m68k
+		vendor=next
+		case $basic_os in
+		    openstep*)
+		        ;;
+		    nextstep*)
 			;;
-		    -ns2*)
-		      os=-nextstep2
+		    ns2*)
+		      basic_os=nextstep2
 			;;
 		    *)
-		      os=-nextstep3
+		      basic_os=nextstep3
 			;;
 		esac
 		;;
-	nh3000)
-		basic_machine=m68k-harris
-		os=-cxux
-		;;
-	nh[45]000)
-		basic_machine=m88k-harris
-		os=-cxux
-		;;
-	nindy960)
-		basic_machine=i960-intel
-		os=-nindy
-		;;
-	mon960)
-		basic_machine=i960-intel
-		os=-mon960
-		;;
-	nonstopux)
-		basic_machine=mips-compaq
-		os=-nonstopux
-		;;
 	np1)
-		basic_machine=np1-gould
-		;;
-	neo-tandem)
-		basic_machine=neo-tandem
-		;;
-	nse-tandem)
-		basic_machine=nse-tandem
-		;;
-	nsr-tandem)
-		basic_machine=nsr-tandem
-		;;
-	nsv-tandem)
-		basic_machine=nsv-tandem
-		;;
-	nsx-tandem)
-		basic_machine=nsx-tandem
+		cpu=np1
+		vendor=gould
 		;;
 	op50n-* | op60c-*)
-		basic_machine=hppa1.1-oki
-		os=-proelf
-		;;
-	openrisc | openrisc-*)
-		basic_machine=or32-unknown
-		;;
-	os400)
-		basic_machine=powerpc-ibm
-		os=-os400
-		;;
-	OSE68000 | ose68000)
-		basic_machine=m68000-ericsson
-		os=-ose
-		;;
-	os68k)
-		basic_machine=m68k-none
-		os=-os68k
+		cpu=hppa1.1
+		vendor=oki
+		basic_os=proelf
 		;;
 	pa-hitachi)
-		basic_machine=hppa1.1-hitachi
-		os=-hiuxwe2
-		;;
-	paragon)
-		basic_machine=i860-intel
-		os=-osf
-		;;
-	parisc)
-		basic_machine=hppa-unknown
-		os=-linux
-		;;
-	parisc-*)
-		basic_machine=hppa-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		os=-linux
+		cpu=hppa1.1
+		vendor=hitachi
+		basic_os=hiuxwe2
 		;;
 	pbd)
-		basic_machine=sparc-tti
+		cpu=sparc
+		vendor=tti
 		;;
 	pbb)
-		basic_machine=m68k-tti
+		cpu=m68k
+		vendor=tti
 		;;
-	pc532 | pc532-*)
-		basic_machine=ns32k-pc532
-		;;
-	pc98)
-		basic_machine=i386-pc
-		;;
-	pc98-*)
-		basic_machine=i386-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	pentium | p5 | k5 | k6 | nexgen | viac3)
-		basic_machine=i586-pc
-		;;
-	pentiumpro | p6 | 6x86 | athlon | athlon_*)
-		basic_machine=i686-pc
-		;;
-	pentiumii | pentium2 | pentiumiii | pentium3)
-		basic_machine=i686-pc
-		;;
-	pentium4)
-		basic_machine=i786-pc
-		;;
-	pentium-* | p5-* | k5-* | k6-* | nexgen-* | viac3-*)
-		basic_machine=i586-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	pentiumpro-* | p6-* | 6x86-* | athlon-*)
-		basic_machine=i686-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	pentiumii-* | pentium2-* | pentiumiii-* | pentium3-*)
-		basic_machine=i686-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	pentium4-*)
-		basic_machine=i786-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	pc532)
+		cpu=ns32k
+		vendor=pc532
 		;;
 	pn)
-		basic_machine=pn-gould
+		cpu=pn
+		vendor=gould
 		;;
-	power)	basic_machine=power-ibm
-		;;
-	ppc | ppcbe)	basic_machine=powerpc-unknown
-		;;
-	ppc-* | ppcbe-*)
-		basic_machine=powerpc-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	ppcle | powerpclittle)
-		basic_machine=powerpcle-unknown
-		;;
-	ppcle-* | powerpclittle-*)
-		basic_machine=powerpcle-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	ppc64)	basic_machine=powerpc64-unknown
-		;;
-	ppc64-*) basic_machine=powerpc64-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	ppc64le | powerpc64little)
-		basic_machine=powerpc64le-unknown
-		;;
-	ppc64le-* | powerpc64little-*)
-		basic_machine=powerpc64le-`echo "$basic_machine" | sed 's/^[^-]*-//'`
+	power)
+		cpu=power
+		vendor=ibm
 		;;
 	ps2)
-		basic_machine=i386-ibm
-		;;
-	pw32)
-		basic_machine=i586-unknown
-		os=-pw32
-		;;
-	rdos | rdos64)
-		basic_machine=x86_64-pc
-		os=-rdos
-		;;
-	rdos32)
-		basic_machine=i386-pc
-		os=-rdos
-		;;
-	rom68k)
-		basic_machine=m68k-rom68k
-		os=-coff
+		cpu=i386
+		vendor=ibm
 		;;
 	rm[46]00)
-		basic_machine=mips-siemens
+		cpu=mips
+		vendor=siemens
 		;;
 	rtpc | rtpc-*)
-		basic_machine=romp-ibm
-		;;
-	s390 | s390-*)
-		basic_machine=s390-ibm
-		;;
-	s390x | s390x-*)
-		basic_machine=s390x-ibm
-		;;
-	sa29200)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	sb1)
-		basic_machine=mipsisa64sb1-unknown
-		;;
-	sb1el)
-		basic_machine=mipsisa64sb1el-unknown
+		cpu=romp
+		vendor=ibm
 		;;
 	sde)
-		basic_machine=mipsisa32-sde
-		os=-elf
-		;;
-	sei)
-		basic_machine=mips-sei
-		os=-seiux
-		;;
-	sequent)
-		basic_machine=i386-sequent
-		;;
-	sh5el)
-		basic_machine=sh5le-unknown
+		cpu=mipsisa32
+		vendor=sde
+		basic_os=${basic_os:-elf}
 		;;
 	simso-wrs)
-		basic_machine=sparclite-wrs
-		os=-vxworks
-		;;
-	sps7)
-		basic_machine=m68k-bull
-		os=-sysv2
-		;;
-	spur)
-		basic_machine=spur-unknown
-		;;
-	st2000)
-		basic_machine=m68k-tandem
-		;;
-	stratus)
-		basic_machine=i860-stratus
-		os=-sysv4
-		;;
-	strongarm-* | thumb-*)
-		basic_machine=arm-`echo "$basic_machine" | sed 's/^[^-]*-//'`
-		;;
-	sun2)
-		basic_machine=m68000-sun
-		;;
-	sun2os3)
-		basic_machine=m68000-sun
-		os=-sunos3
-		;;
-	sun2os4)
-		basic_machine=m68000-sun
-		os=-sunos4
-		;;
-	sun3os3)
-		basic_machine=m68k-sun
-		os=-sunos3
-		;;
-	sun3os4)
-		basic_machine=m68k-sun
-		os=-sunos4
-		;;
-	sun4os3)
-		basic_machine=sparc-sun
-		os=-sunos3
-		;;
-	sun4os4)
-		basic_machine=sparc-sun
-		os=-sunos4
-		;;
-	sun4sol2)
-		basic_machine=sparc-sun
-		os=-solaris2
-		;;
-	sun3 | sun3-*)
-		basic_machine=m68k-sun
-		;;
-	sun4)
-		basic_machine=sparc-sun
-		;;
-	sun386 | sun386i | roadrunner)
-		basic_machine=i386-sun
-		;;
-	sv1)
-		basic_machine=sv1-cray
-		os=-unicos
-		;;
-	symmetry)
-		basic_machine=i386-sequent
-		os=-dynix
-		;;
-	t3e)
-		basic_machine=alphaev5-cray
-		os=-unicos
-		;;
-	t90)
-		basic_machine=t90-cray
-		os=-unicos
-		;;
-	tile*)
-		basic_machine=$basic_machine-unknown
-		os=-linux-gnu
-		;;
-	tx39)
-		basic_machine=mipstx39-unknown
-		;;
-	tx39el)
-		basic_machine=mipstx39el-unknown
-		;;
-	toad1)
-		basic_machine=pdp10-xkl
-		os=-tops20
+		cpu=sparclite
+		vendor=wrs
+		basic_os=vxworks
 		;;
 	tower | tower-32)
-		basic_machine=m68k-ncr
-		;;
-	tpf)
-		basic_machine=s390x-ibm
-		os=-tpf
-		;;
-	udi29k)
-		basic_machine=a29k-amd
-		os=-udi
-		;;
-	ultra3)
-		basic_machine=a29k-nyu
-		os=-sym1
-		;;
-	v810 | necv810)
-		basic_machine=v810-nec
-		os=-none
-		;;
-	vaxv)
-		basic_machine=vax-dec
-		os=-sysv
-		;;
-	vms)
-		basic_machine=vax-dec
-		os=-vms
+		cpu=m68k
+		vendor=ncr
 		;;
 	vpp*|vx|vx-*)
-		basic_machine=f301-fujitsu
+		cpu=f301
+		vendor=fujitsu
 		;;
-	vxworks960)
-		basic_machine=i960-wrs
-		os=-vxworks
-		;;
-	vxworks68)
-		basic_machine=m68k-wrs
-		os=-vxworks
-		;;
-	vxworks29k)
-		basic_machine=a29k-wrs
-		os=-vxworks
-		;;
-	w65*)
-		basic_machine=w65-wdc
-		os=-none
+	w65)
+		cpu=w65
+		vendor=wdc
 		;;
 	w89k-*)
-		basic_machine=hppa1.1-winbond
-		os=-proelf
-		;;
-	x64)
-		basic_machine=x86_64-pc
-		;;
-	xbox)
-		basic_machine=i686-pc
-		os=-mingw32
-		;;
-	xps | xps100)
-		basic_machine=xps100-honeywell
-		;;
-	xscale-* | xscalee[bl]-*)
-		basic_machine=`echo "$basic_machine" | sed 's/^xscale/arm/'`
-		;;
-	ymp)
-		basic_machine=ymp-cray
-		os=-unicos
+		cpu=hppa1.1
+		vendor=winbond
+		basic_os=proelf
 		;;
 	none)
-		basic_machine=none-none
-		os=-none
+		cpu=none
+		vendor=none
+		;;
+	leon|leon[3-9])
+		cpu=sparc
+		vendor=$basic_machine
+		;;
+	leon-*|leon[3-9]-*)
+		cpu=sparc
+		vendor=`echo "$basic_machine" | sed 's/-.*//'`
 		;;
 
-# Here we handle the default manufacturer of certain CPU types.  It is in
-# some cases the only manufacturer, in others, it is the most popular.
-	w89k)
-		basic_machine=hppa1.1-winbond
+	*-*)
+		# shellcheck disable=SC2162
+		saved_IFS=$IFS
+		IFS="-" read cpu vendor <<EOF
+$basic_machine
+EOF
+		IFS=$saved_IFS
 		;;
-	op50n)
-		basic_machine=hppa1.1-oki
+	# We use 'pc' rather than 'unknown'
+	# because (1) that's what they normally are, and
+	# (2) the word "unknown" tends to confuse beginning users.
+	i*86 | x86_64)
+		cpu=$basic_machine
+		vendor=pc
 		;;
-	op60c)
-		basic_machine=hppa1.1-oki
+	# These rules are duplicated from below for sake of the special case above;
+	# i.e. things that normalized to x86 arches should also default to "pc"
+	pc98)
+		cpu=i386
+		vendor=pc
 		;;
-	romp)
-		basic_machine=romp-ibm
+	x64 | amd64)
+		cpu=x86_64
+		vendor=pc
 		;;
-	mmix)
-		basic_machine=mmix-knuth
-		;;
-	rs6000)
-		basic_machine=rs6000-ibm
-		;;
-	vax)
-		basic_machine=vax-dec
-		;;
-	pdp11)
-		basic_machine=pdp11-dec
-		;;
-	we32k)
-		basic_machine=we32k-att
-		;;
-	sh[1234] | sh[24]a | sh[24]aeb | sh[34]eb | sh[1234]le | sh[23]ele)
-		basic_machine=sh-unknown
-		;;
-	cydra)
-		basic_machine=cydra-cydrome
-		;;
-	orion)
-		basic_machine=orion-highlevel
-		;;
-	orion105)
-		basic_machine=clipper-highlevel
-		;;
-	mac | mpw | mac-mpw)
-		basic_machine=m68k-apple
-		;;
-	pmac | pmac-mpw)
-		basic_machine=powerpc-apple
-		;;
-	*-unknown)
-		# Make sure to match an already-canonicalized machine name.
-		;;
+	# Recognize the basic CPU types without company name.
 	*)
-		echo Invalid configuration \`"$1"\': machine \`"$basic_machine"\' not recognized 1>&2
-		exit 1
+		cpu=$basic_machine
+		vendor=unknown
+		;;
+esac
+
+unset -v basic_machine
+
+# Decode basic machines in the full and proper CPU-Company form.
+case $cpu-$vendor in
+	# Here we handle the default manufacturer of certain CPU types in canonical form. It is in
+	# some cases the only manufacturer, in others, it is the most popular.
+	craynv-unknown)
+		vendor=cray
+		basic_os=${basic_os:-unicosmp}
+		;;
+	c90-unknown | c90-cray)
+		vendor=cray
+		basic_os=${Basic_os:-unicos}
+		;;
+	fx80-unknown)
+		vendor=alliant
+		;;
+	romp-unknown)
+		vendor=ibm
+		;;
+	mmix-unknown)
+		vendor=knuth
+		;;
+	microblaze-unknown | microblazeel-unknown)
+		vendor=xilinx
+		;;
+	rs6000-unknown)
+		vendor=ibm
+		;;
+	vax-unknown)
+		vendor=dec
+		;;
+	pdp11-unknown)
+		vendor=dec
+		;;
+	we32k-unknown)
+		vendor=att
+		;;
+	cydra-unknown)
+		vendor=cydrome
+		;;
+	i370-ibm*)
+		vendor=ibm
+		;;
+	orion-unknown)
+		vendor=highlevel
+		;;
+	xps-unknown | xps100-unknown)
+		cpu=xps100
+		vendor=honeywell
+		;;
+
+	# Here we normalize CPU types with a missing or matching vendor
+	armh-unknown | armh-alt)
+		cpu=armv7l
+		vendor=alt
+		basic_os=${basic_os:-linux-gnueabihf}
+		;;
+	dpx20-unknown | dpx20-bull)
+		cpu=rs6000
+		vendor=bull
+		basic_os=${basic_os:-bosx}
+		;;
+
+	# Here we normalize CPU types irrespective of the vendor
+	amd64-*)
+		cpu=x86_64
+		;;
+	blackfin-*)
+		cpu=bfin
+		basic_os=linux
+		;;
+	c54x-*)
+		cpu=tic54x
+		;;
+	c55x-*)
+		cpu=tic55x
+		;;
+	c6x-*)
+		cpu=tic6x
+		;;
+	e500v[12]-*)
+		cpu=powerpc
+		basic_os=${basic_os}"spe"
+		;;
+	mips3*-*)
+		cpu=mips64
+		;;
+	ms1-*)
+		cpu=mt
+		;;
+	m68knommu-*)
+		cpu=m68k
+		basic_os=linux
+		;;
+	m9s12z-* | m68hcs12z-* | hcs12z-* | s12z-*)
+		cpu=s12z
+		;;
+	openrisc-*)
+		cpu=or32
+		;;
+	parisc-*)
+		cpu=hppa
+		basic_os=linux
+		;;
+	pentium-* | p5-* | k5-* | k6-* | nexgen-* | viac3-*)
+		cpu=i586
+		;;
+	pentiumpro-* | p6-* | 6x86-* | athlon-* | athlon_*-*)
+		cpu=i686
+		;;
+	pentiumii-* | pentium2-* | pentiumiii-* | pentium3-*)
+		cpu=i686
+		;;
+	pentium4-*)
+		cpu=i786
+		;;
+	pc98-*)
+		cpu=i386
+		;;
+	ppc-* | ppcbe-*)
+		cpu=powerpc
+		;;
+	ppcle-* | powerpclittle-*)
+		cpu=powerpcle
+		;;
+	ppc64-*)
+		cpu=powerpc64
+		;;
+	ppc64le-* | powerpc64little-*)
+		cpu=powerpc64le
+		;;
+	sb1-*)
+		cpu=mipsisa64sb1
+		;;
+	sb1el-*)
+		cpu=mipsisa64sb1el
+		;;
+	sh5e[lb]-*)
+		cpu=`echo "$cpu" | sed 's/^\(sh.\)e\(.\)$/\1\2e/'`
+		;;
+	spur-*)
+		cpu=spur
+		;;
+	strongarm-* | thumb-*)
+		cpu=arm
+		;;
+	tx39-*)
+		cpu=mipstx39
+		;;
+	tx39el-*)
+		cpu=mipstx39el
+		;;
+	x64-*)
+		cpu=x86_64
+		;;
+	xscale-* | xscalee[bl]-*)
+		cpu=`echo "$cpu" | sed 's/^xscale/arm/'`
+		;;
+	arm64-* | aarch64le-*)
+		cpu=aarch64
+		;;
+
+	# Recognize the canonical CPU Types that limit and/or modify the
+	# company names they are paired with.
+	cr16-*)
+		basic_os=${basic_os:-elf}
+		;;
+	crisv32-* | etraxfs*-*)
+		cpu=crisv32
+		vendor=axis
+		;;
+	cris-* | etrax*-*)
+		cpu=cris
+		vendor=axis
+		;;
+	crx-*)
+		basic_os=${basic_os:-elf}
+		;;
+	neo-tandem)
+		cpu=neo
+		vendor=tandem
+		;;
+	nse-tandem)
+		cpu=nse
+		vendor=tandem
+		;;
+	nsr-tandem)
+		cpu=nsr
+		vendor=tandem
+		;;
+	nsv-tandem)
+		cpu=nsv
+		vendor=tandem
+		;;
+	nsx-tandem)
+		cpu=nsx
+		vendor=tandem
+		;;
+	mipsallegrexel-sony)
+		cpu=mipsallegrexel
+		vendor=sony
+		;;
+	tile*-*)
+		basic_os=${basic_os:-linux-gnu}
+		;;
+
+	*)
+		# Recognize the canonical CPU types that are allowed with any
+		# company name.
+		case $cpu in
+			1750a | 580 \
+			| a29k \
+			| aarch64 | aarch64_be | aarch64c | arm64ec \
+			| abacus \
+			| alpha | alphaev[4-8] | alphaev56 | alphaev6[78] \
+			| alpha64 | alpha64ev[4-8] | alpha64ev56 | alpha64ev6[78] \
+			| alphapca5[67] | alpha64pca5[67] \
+			| am33_2.0 \
+			| amdgcn \
+			| arc | arceb | arc32 | arc64 \
+			| arm | arm[lb]e | arme[lb] | armv* \
+			| avr | avr32 \
+			| asmjs \
+			| ba \
+			| be32 | be64 \
+			| bfin | bpf | bs2000 \
+			| c[123]* | c30 | [cjt]90 | c4x \
+			| c8051 | clipper | craynv | csky | cydra \
+			| d10v | d30v | dlx | dsp16xx \
+			| e2k | elxsi | epiphany \
+			| f30[01] | f700 | fido | fr30 | frv | ft32 | fx80 \
+			| javascript \
+			| h8300 | h8500 \
+			| hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
+			| hexagon \
+			| i370 | i*86 | i860 | i960 | ia16 | ia64 \
+			| ip2k | iq2000 \
+			| k1om \
+			| kvx \
+			| le32 | le64 \
+			| lm32 \
+			| loongarch32 | loongarch64 \
+			| m32c | m32r | m32rle \
+			| m5200 | m68000 | m680[012346]0 | m68360 | m683?2 | m68k \
+			| m6811 | m68hc11 | m6812 | m68hc12 | m68hcs12x \
+			| m88110 | m88k | maxq | mb | mcore | mep | metag \
+			| microblaze | microblazeel \
+			| mips* \
+			| mmix \
+			| mn10200 | mn10300 \
+			| moxie \
+			| mt \
+			| msp430 \
+			| nds32 | nds32le | nds32be \
+			| nfp \
+			| nios | nios2 | nios2eb | nios2el \
+			| none | np1 | ns16k | ns32k | nvptx \
+			| open8 \
+			| or1k* \
+			| or32 \
+			| orion \
+			| picochip \
+			| pdp10 | pdp11 | pj | pjl | pn | power \
+			| powerpc | powerpc64 | powerpc64le | powerpcle | powerpcspe \
+			| pru \
+			| pyramid \
+			| riscv | riscv32 | riscv32be | riscv64 | riscv64be \
+			| rl78 | romp | rs6000 | rx \
+			| s390 | s390x \
+			| score \
+			| sh | shl \
+			| sh[1234] | sh[24]a | sh[24]ae[lb] | sh[23]e | she[lb] | sh[lb]e \
+			| sh[1234]e[lb] |  sh[12345][lb]e | sh[23]ele | sh64 | sh64le \
+			| sparc | sparc64 | sparc64b | sparc64v | sparc86x | sparclet \
+			| sparclite \
+			| sparcv8 | sparcv9 | sparcv9b | sparcv9v | sv1 | sx* \
+			| spu \
+			| tahoe \
+			| thumbv7* \
+			| tic30 | tic4x | tic54x | tic55x | tic6x | tic80 \
+			| tron \
+			| ubicom32 \
+			| v70 | v850 | v850e | v850e1 | v850es | v850e2 | v850e2v3 \
+			| vax \
+			| visium \
+			| w65 \
+			| wasm32 | wasm64 \
+			| we32k \
+			| x86 | x86_64 | xc16x | xgate | xps100 \
+			| xstormy16 | xtensa* \
+			| ymp \
+			| z8k | z80)
+				;;
+
+			*)
+				echo "Invalid configuration '$1': machine '$cpu-$vendor' not recognized" 1>&2
+				exit 1
+				;;
+		esac
 		;;
 esac
 
 # Here we canonicalize certain aliases for manufacturers.
-case $basic_machine in
-	*-digital*)
-		basic_machine=`echo "$basic_machine" | sed 's/digital.*/dec/'`
+case $vendor in
+	digital*)
+		vendor=dec
 		;;
-	*-commodore*)
-		basic_machine=`echo "$basic_machine" | sed 's/commodore.*/cbm/'`
+	commodore*)
+		vendor=cbm
 		;;
 	*)
 		;;
@@ -1334,203 +1285,226 @@
 
 # Decode manufacturer-specific aliases for certain operating systems.
 
-if [ x"$os" != x"" ]
+if test x"$basic_os" != x
 then
+
+# First recognize some ad-hoc cases, or perhaps split kernel-os, or else just
+# set os.
+obj=
+case $basic_os in
+	gnu/linux*)
+		kernel=linux
+		os=`echo "$basic_os" | sed -e 's|gnu/linux|gnu|'`
+		;;
+	os2-emx)
+		kernel=os2
+		os=`echo "$basic_os" | sed -e 's|os2-emx|emx|'`
+		;;
+	nto-qnx*)
+		kernel=nto
+		os=`echo "$basic_os" | sed -e 's|nto-qnx|qnx|'`
+		;;
+	*-*)
+		# shellcheck disable=SC2162
+		saved_IFS=$IFS
+		IFS="-" read kernel os <<EOF
+$basic_os
+EOF
+		IFS=$saved_IFS
+		;;
+	# Default OS when just kernel was specified
+	nto*)
+		kernel=nto
+		os=`echo "$basic_os" | sed -e 's|nto|qnx|'`
+		;;
+	linux*)
+		kernel=linux
+		os=`echo "$basic_os" | sed -e 's|linux|gnu|'`
+		;;
+	managarm*)
+		kernel=managarm
+		os=`echo "$basic_os" | sed -e 's|managarm|mlibc|'`
+		;;
+	*)
+		kernel=
+		os=$basic_os
+		;;
+esac
+
+# Now, normalize the OS (knowing we just have one component, it's not a kernel,
+# etc.)
 case $os in
 	# First match some system type aliases that might get confused
 	# with valid system types.
-	# -solaris* is a basic system type, with this one exception.
-	-auroraux)
-		os=-auroraux
+	# solaris* is a basic system type, with this one exception.
+	auroraux)
+		os=auroraux
 		;;
-	-solaris1 | -solaris1.*)
-		os=`echo $os | sed -e 's|solaris1|sunos4|'`
+	bluegene*)
+		os=cnk
 		;;
-	-solaris)
-		os=-solaris2
+	solaris1 | solaris1.*)
+		os=`echo "$os" | sed -e 's|solaris1|sunos4|'`
 		;;
-	-unixware*)
-		os=-sysv4.2uw
+	solaris)
+		os=solaris2
 		;;
-	-gnu/linux*)
-		os=`echo $os | sed -e 's|gnu/linux|linux-gnu|'`
+	unixware*)
+		os=sysv4.2uw
 		;;
 	# es1800 is here to avoid being matched by es* (a different OS)
-	-es1800*)
-		os=-ose
+	es1800*)
+		os=ose
 		;;
-	# Now accept the basic system types.
-	# The portable systems comes first.
-	# Each alternative MUST end in a * to match a version number.
-	# -sysv* is not here because it comes later, after sysvr4.
-	-gnu* | -bsd* | -mach* | -minix* | -genix* | -ultrix* | -irix* \
-	      | -*vms* | -sco* | -esix* | -isc* | -aix* | -cnk* | -sunos | -sunos[34]*\
-	      | -hpux* | -unos* | -osf* | -luna* | -dgux* | -auroraux* | -solaris* \
-	      | -sym* | -kopensolaris* | -plan9* \
-	      | -amigaos* | -amigados* | -msdos* | -newsos* | -unicos* | -aof* \
-	      | -aos* | -aros* | -cloudabi* | -sortix* \
-	      | -nindy* | -vxsim* | -vxworks* | -ebmon* | -hms* | -mvs* \
-	      | -clix* | -riscos* | -uniplus* | -iris* | -rtu* | -xenix* \
-	      | -hiux* | -knetbsd* | -mirbsd* | -netbsd* \
-	      | -bitrig* | -openbsd* | -solidbsd* | -libertybsd* \
-	      | -ekkobsd* | -kfreebsd* | -freebsd* | -riscix* | -lynxos* \
-	      | -bosx* | -nextstep* | -cxux* | -aout* | -elf* | -oabi* \
-	      | -ptx* | -coff* | -ecoff* | -winnt* | -domain* | -vsta* \
-	      | -udi* | -eabi* | -lites* | -ieee* | -go32* | -aux* | -hcos* \
-	      | -chorusos* | -chorusrdb* | -cegcc* | -glidix* \
-	      | -cygwin* | -msys* | -pe* | -psos* | -moss* | -proelf* | -rtems* \
-	      | -midipix* | -mingw32* | -mingw64* | -linux-gnu* | -linux-android* \
-	      | -linux-newlib* | -linux-musl* | -linux-uclibc* \
-	      | -uxpv* | -beos* | -mpeix* | -udk* | -moxiebox* \
-	      | -interix* | -uwin* | -mks* | -rhapsody* | -darwin* \
-	      | -openstep* | -oskit* | -conix* | -pw32* | -nonstopux* \
-	      | -storm-chaos* | -tops10* | -tenex* | -tops20* | -its* \
-	      | -os2* | -vos* | -palmos* | -uclinux* | -nucleus* \
-	      | -morphos* | -superux* | -rtmk* | -windiss* \
-	      | -powermax* | -dnix* | -nx6 | -nx7 | -sei* | -dragonfly* \
-	      | -skyos* | -haiku* | -rdos* | -toppers* | -drops* | -es* \
-	      | -onefs* | -tirtos* | -phoenix* | -fuchsia* | -redox* | -bme* \
-	      | -midnightbsd*)
-	# Remember, each alternative MUST END IN *, to match a version number.
+	# Some version numbers need modification
+	chorusos*)
+		os=chorusos
 		;;
-	-qnx*)
-		case $basic_machine in
-		    x86-* | i*86-*)
-			;;
-		    *)
-			os=-nto$os
-			;;
-		esac
+	isc)
+		os=isc2.2
 		;;
-	-nto-qnx*)
+	sco6)
+		os=sco5v6
 		;;
-	-nto*)
-		os=`echo $os | sed -e 's|nto|nto-qnx|'`
+	sco5)
+		os=sco3.2v5
 		;;
-	-sim | -xray | -os68k* | -v88r* \
-	      | -windows* | -osx | -abug | -netware* | -os9* \
-	      | -macos* | -mpw* | -magic* | -mmixware* | -mon960* | -lnews*)
+	sco4)
+		os=sco3.2v4
 		;;
-	-mac*)
+	sco3.2.[4-9]*)
+		os=`echo "$os" | sed -e 's/sco3.2./sco3.2v/'`
+		;;
+	sco*v* | scout)
+		# Don't match below
+		;;
+	sco*)
+		os=sco3.2v2
+		;;
+	psos*)
+		os=psos
+		;;
+	qnx*)
+		os=qnx
+		;;
+	hiux*)
+		os=hiuxwe2
+		;;
+	lynx*178)
+		os=lynxos178
+		;;
+	lynx*5)
+		os=lynxos5
+		;;
+	lynxos*)
+		# don't get caught up in next wildcard
+		;;
+	lynx*)
+		os=lynxos
+		;;
+	mac[0-9]*)
 		os=`echo "$os" | sed -e 's|mac|macos|'`
 		;;
-	-linux-dietlibc)
-		os=-linux-dietlibc
+	opened*)
+		os=openedition
 		;;
-	-linux*)
-		os=`echo $os | sed -e 's|linux|linux-gnu|'`
+	os400*)
+		os=os400
 		;;
-	-sunos5*)
+	sunos5*)
 		os=`echo "$os" | sed -e 's|sunos5|solaris2|'`
 		;;
-	-sunos6*)
+	sunos6*)
 		os=`echo "$os" | sed -e 's|sunos6|solaris3|'`
 		;;
-	-opened*)
-		os=-openedition
+	wince*)
+		os=wince
 		;;
-	-os400*)
-		os=-os400
+	utek*)
+		os=bsd
 		;;
-	-wince*)
-		os=-wince
+	dynix*)
+		os=bsd
 		;;
-	-utek*)
-		os=-bsd
+	acis*)
+		os=aos
 		;;
-	-dynix*)
-		os=-bsd
+	atheos*)
+		os=atheos
 		;;
-	-acis*)
-		os=-aos
+	syllable*)
+		os=syllable
 		;;
-	-atheos*)
-		os=-atheos
+	386bsd)
+		os=bsd
 		;;
-	-syllable*)
-		os=-syllable
+	ctix* | uts*)
+		os=sysv
 		;;
-	-386bsd)
-		os=-bsd
+	nova*)
+		os=rtmk-nova
 		;;
-	-ctix* | -uts*)
-		os=-sysv
-		;;
-	-nova*)
-		os=-rtmk-nova
-		;;
-	-ns2)
-		os=-nextstep2
-		;;
-	-nsk*)
-		os=-nsk
+	ns2)
+		os=nextstep2
 		;;
 	# Preserve the version number of sinix5.
-	-sinix5.*)
-		os=`echo $os | sed -e 's|sinix|sysv|'`
+	sinix5.*)
+		os=`echo "$os" | sed -e 's|sinix|sysv|'`
 		;;
-	-sinix*)
-		os=-sysv4
+	sinix*)
+		os=sysv4
 		;;
-	-tpf*)
-		os=-tpf
+	tpf*)
+		os=tpf
 		;;
-	-triton*)
-		os=-sysv3
+	triton*)
+		os=sysv3
 		;;
-	-oss*)
-		os=-sysv3
+	oss*)
+		os=sysv3
 		;;
-	-svr4*)
-		os=-sysv4
+	svr4*)
+		os=sysv4
 		;;
-	-svr3)
-		os=-sysv3
+	svr3)
+		os=sysv3
 		;;
-	-sysvr4)
-		os=-sysv4
+	sysvr4)
+		os=sysv4
 		;;
-	# This must come after -sysvr4.
-	-sysv*)
+	ose*)
+		os=ose
 		;;
-	-ose*)
-		os=-ose
+	*mint | mint[0-9]* | *MiNT | MiNT[0-9]*)
+		os=mint
 		;;
-	-*mint | -mint[0-9]* | -*MiNT | -MiNT[0-9]*)
-		os=-mint
+	dicos*)
+		os=dicos
 		;;
-	-zvmoe)
-		os=-zvmoe
-		;;
-	-dicos*)
-		os=-dicos
-		;;
-	-pikeos*)
+	pikeos*)
 		# Until real need of OS specific support for
 		# particular features comes up, bare metal
 		# configurations are quite functional.
-		case $basic_machine in
+		case $cpu in
 		    arm*)
-			os=-eabi
+			os=eabi
 			;;
 		    *)
-			os=-elf
+			os=
+			obj=elf
 			;;
 		esac
 		;;
-	-nacl*)
-		;;
-	-ios)
-		;;
-	-none)
+	aout* | coff* | elf* | pe*)
+		# These are machine code file formats, not OSes
+		obj=$os
+		os=
 		;;
 	*)
-		# Get rid of the `-' at the beginning of $os.
-		os=`echo $os | sed 's/[^-]*-//'`
-		echo Invalid configuration \`"$1"\': system \`"$os"\' not recognized 1>&2
-		exit 1
+		# No normalization, but not necessarily accepted, that comes below.
 		;;
 esac
+
 else
 
 # Here we handle the default operating systems that come with various machines.
@@ -1543,254 +1517,439 @@
 # will signal an error saying that MANUFACTURER isn't an operating
 # system, and we'll never get to this point.
 
-case $basic_machine in
+kernel=
+obj=
+case $cpu-$vendor in
 	score-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	spu-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	*-acorn)
-		os=-riscix1.2
+		os=riscix1.2
 		;;
 	arm*-rebel)
-		os=-linux
+		kernel=linux
+		os=gnu
 		;;
 	arm*-semi)
-		os=-aout
+		os=
+		obj=aout
 		;;
 	c4x-* | tic4x-*)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	c8051-*)
-		os=-elf
+		os=
+		obj=elf
+		;;
+	clipper-intergraph)
+		os=clix
 		;;
 	hexagon-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	tic54x-*)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	tic55x-*)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	tic6x-*)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	# This must come before the *-dec entry.
 	pdp10-*)
-		os=-tops20
+		os=tops20
 		;;
 	pdp11-*)
-		os=-none
+		os=none
 		;;
 	*-dec | vax-*)
-		os=-ultrix4.2
+		os=ultrix4.2
 		;;
 	m68*-apollo)
-		os=-domain
+		os=domain
 		;;
 	i386-sun)
-		os=-sunos4.0.2
+		os=sunos4.0.2
 		;;
 	m68000-sun)
-		os=-sunos3
+		os=sunos3
 		;;
 	m68*-cisco)
-		os=-aout
+		os=
+		obj=aout
 		;;
 	mep-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	mips*-cisco)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	mips*-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	or32-*)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	*-tti)	# must be before sparc entry or we get the wrong os.
-		os=-sysv3
+		os=sysv3
 		;;
 	sparc-* | *-sun)
-		os=-sunos4.1.1
+		os=sunos4.1.1
 		;;
 	pru-*)
-		os=-elf
+		os=
+		obj=elf
 		;;
 	*-be)
-		os=-beos
+		os=beos
 		;;
 	*-ibm)
-		os=-aix
+		os=aix
 		;;
 	*-knuth)
-		os=-mmixware
+		os=mmixware
 		;;
 	*-wec)
-		os=-proelf
+		os=proelf
 		;;
 	*-winbond)
-		os=-proelf
+		os=proelf
 		;;
 	*-oki)
-		os=-proelf
+		os=proelf
 		;;
 	*-hp)
-		os=-hpux
+		os=hpux
 		;;
 	*-hitachi)
-		os=-hiux
+		os=hiux
 		;;
 	i860-* | *-att | *-ncr | *-altos | *-motorola | *-convergent)
-		os=-sysv
+		os=sysv
 		;;
 	*-cbm)
-		os=-amigaos
+		os=amigaos
 		;;
 	*-dg)
-		os=-dgux
+		os=dgux
 		;;
 	*-dolphin)
-		os=-sysv3
+		os=sysv3
 		;;
 	m68k-ccur)
-		os=-rtu
+		os=rtu
 		;;
 	m88k-omron*)
-		os=-luna
+		os=luna
 		;;
 	*-next)
-		os=-nextstep
+		os=nextstep
 		;;
 	*-sequent)
-		os=-ptx
+		os=ptx
 		;;
 	*-crds)
-		os=-unos
+		os=unos
 		;;
 	*-ns)
-		os=-genix
+		os=genix
 		;;
 	i370-*)
-		os=-mvs
+		os=mvs
 		;;
 	*-gould)
-		os=-sysv
+		os=sysv
 		;;
 	*-highlevel)
-		os=-bsd
+		os=bsd
 		;;
 	*-encore)
-		os=-bsd
+		os=bsd
 		;;
 	*-sgi)
-		os=-irix
+		os=irix
 		;;
 	*-siemens)
-		os=-sysv4
+		os=sysv4
 		;;
 	*-masscomp)
-		os=-rtu
+		os=rtu
 		;;
 	f30[01]-fujitsu | f700-fujitsu)
-		os=-uxpv
+		os=uxpv
 		;;
 	*-rom68k)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	*-*bug)
-		os=-coff
+		os=
+		obj=coff
 		;;
 	*-apple)
-		os=-macos
+		os=macos
 		;;
 	*-atari*)
-		os=-mint
+		os=mint
+		;;
+	*-wrs)
+		os=vxworks
 		;;
 	*)
-		os=-none
+		os=none
 		;;
 esac
+
 fi
 
+# Now, validate our (potentially fixed-up) individual pieces (OS, OBJ).
+
+case $os in
+	# Sometimes we do "kernel-libc", so those need to count as OSes.
+	musl* | newlib* | relibc* | uclibc*)
+		;;
+	# Likewise for "kernel-abi"
+	eabi* | gnueabi*)
+		;;
+	# VxWorks passes extra cpu info in the 4th filed.
+	simlinux | simwindows | spe)
+		;;
+	# See `case $cpu-$os` validation below
+	ghcjs)
+		;;
+	# Now accept the basic system types.
+	# The portable systems comes first.
+	# Each alternative MUST end in a * to match a version number.
+	gnu* | android* | bsd* | mach* | minix* | genix* | ultrix* | irix* \
+	     | *vms* | esix* | aix* | cnk* | sunos | sunos[34]* \
+	     | hpux* | unos* | osf* | luna* | dgux* | auroraux* | solaris* \
+	     | sym* |  plan9* | psp* | sim* | xray* | os68k* | v88r* \
+	     | hiux* | abug | nacl* | netware* | windows* \
+	     | os9* | macos* | osx* | ios* | tvos* | watchos* \
+	     | mpw* | magic* | mmixware* | mon960* | lnews* \
+	     | amigaos* | amigados* | msdos* | newsos* | unicos* | aof* \
+	     | aos* | aros* | cloudabi* | sortix* | twizzler* \
+	     | nindy* | vxsim* | vxworks* | ebmon* | hms* | mvs* \
+	     | clix* | riscos* | uniplus* | iris* | isc* | rtu* | xenix* \
+	     | mirbsd* | netbsd* | dicos* | openedition* | ose* \
+	     | bitrig* | openbsd* | secbsd* | solidbsd* | libertybsd* | os108* \
+	     | ekkobsd* | freebsd* | riscix* | lynxos* | os400* \
+	     | bosx* | nextstep* | cxux* | oabi* \
+	     | ptx* | ecoff* | winnt* | domain* | vsta* \
+	     | udi* | lites* | ieee* | go32* | aux* | hcos* \
+	     | chorusrdb* | cegcc* | glidix* | serenity* \
+	     | cygwin* | msys* | moss* | proelf* | rtems* \
+	     | midipix* | mingw32* | mingw64* | mint* \
+	     | uxpv* | beos* | mpeix* | udk* | moxiebox* \
+	     | interix* | uwin* | mks* | rhapsody* | darwin* \
+	     | openstep* | oskit* | conix* | pw32* | nonstopux* \
+	     | storm-chaos* | tops10* | tenex* | tops20* | its* \
+	     | os2* | vos* | palmos* | uclinux* | nucleus* | morphos* \
+	     | scout* | superux* | sysv* | rtmk* | tpf* | windiss* \
+	     | powermax* | dnix* | nx6 | nx7 | sei* | dragonfly* \
+	     | skyos* | haiku* | rdos* | toppers* | drops* | es* \
+	     | onefs* | tirtos* | phoenix* | fuchsia* | redox* | bme* \
+	     | midnightbsd* | amdhsa* | unleashed* | emscripten* | wasi* \
+	     | nsk* | powerunix* | genode* | zvmoe* | qnx* | emx* | zephyr* \
+	     | fiwix* | mlibc* | cos* | mbr* )
+		;;
+	# This one is extra strict with allowed versions
+	sco3.2v2 | sco3.2v[4-9]* | sco5v6*)
+		# Don't forget version if it is 3.2v4 or newer.
+		;;
+	none)
+		;;
+	kernel* | msvc* )
+		# Restricted further below
+		;;
+	'')
+		if test x"$obj" = x
+		then
+			echo "Invalid configuration '$1': Blank OS only allowed with explicit machine code file format" 1>&2
+		fi
+		;;
+	*)
+		echo "Invalid configuration '$1': OS '$os' not recognized" 1>&2
+		exit 1
+		;;
+esac
+
+case $obj in
+	aout* | coff* | elf* | pe*)
+		;;
+	'')
+		# empty is fine
+		;;
+	*)
+		echo "Invalid configuration '$1': Machine code format '$obj' not recognized" 1>&2
+		exit 1
+		;;
+esac
+
+# Here we handle the constraint that a (synthetic) cpu and os are
+# valid only in combination with each other and nowhere else.
+case $cpu-$os in
+	# The "javascript-unknown-ghcjs" triple is used by GHC; we
+	# accept it here in order to tolerate that, but reject any
+	# variations.
+	javascript-ghcjs)
+		;;
+	javascript-* | *-ghcjs)
+		echo "Invalid configuration '$1': cpu '$cpu' is not valid with os '$os$obj'" 1>&2
+		exit 1
+		;;
+esac
+
+# As a final step for OS-related things, validate the OS-kernel combination
+# (given a valid OS), if there is a kernel.
+case $kernel-$os-$obj in
+	linux-gnu*- | linux-dietlibc*- | linux-android*- | linux-newlib*- \
+		   | linux-musl*- | linux-relibc*- | linux-uclibc*- | linux-mlibc*- )
+		;;
+	uclinux-uclibc*- )
+		;;
+	managarm-mlibc*- | managarm-kernel*- )
+		;;
+	windows*-msvc*-)
+		;;
+	-dietlibc*- | -newlib*- | -musl*- | -relibc*- | -uclibc*- | -mlibc*- )
+		# These are just libc implementations, not actual OSes, and thus
+		# require a kernel.
+		echo "Invalid configuration '$1': libc '$os' needs explicit kernel." 1>&2
+		exit 1
+		;;
+	-kernel*- )
+		echo "Invalid configuration '$1': '$os' needs explicit kernel." 1>&2
+		exit 1
+		;;
+	*-kernel*- )
+		echo "Invalid configuration '$1': '$kernel' does not support '$os'." 1>&2
+		exit 1
+		;;
+	*-msvc*- )
+		echo "Invalid configuration '$1': '$os' needs 'windows'." 1>&2
+		exit 1
+		;;
+	kfreebsd*-gnu*- | kopensolaris*-gnu*-)
+		;;
+	vxworks-simlinux- | vxworks-simwindows- | vxworks-spe-)
+		;;
+	nto-qnx*-)
+		;;
+	os2-emx-)
+		;;
+	*-eabi*- | *-gnueabi*-)
+		;;
+	none--*)
+		# None (no kernel, i.e. freestanding / bare metal),
+		# can be paired with an machine code file format
+		;;
+	-*-)
+		# Blank kernel with real OS is always fine.
+		;;
+	--*)
+		# Blank kernel and OS with real machine code file format is always fine.
+		;;
+	*-*-*)
+		echo "Invalid configuration '$1': Kernel '$kernel' not known to work with OS '$os'." 1>&2
+		exit 1
+		;;
+esac
+
 # Here we handle the case where we know the os, and the CPU type, but not the
 # manufacturer.  We pick the logical manufacturer.
-vendor=unknown
-case $basic_machine in
-	*-unknown)
-		case $os in
-			-riscix*)
+case $vendor in
+	unknown)
+		case $cpu-$os in
+			*-riscix*)
 				vendor=acorn
 				;;
-			-sunos*)
+			*-sunos*)
 				vendor=sun
 				;;
-			-cnk*|-aix*)
+			*-cnk* | *-aix*)
 				vendor=ibm
 				;;
-			-beos*)
+			*-beos*)
 				vendor=be
 				;;
-			-hpux*)
+			*-hpux*)
 				vendor=hp
 				;;
-			-mpeix*)
+			*-mpeix*)
 				vendor=hp
 				;;
-			-hiux*)
+			*-hiux*)
 				vendor=hitachi
 				;;
-			-unos*)
+			*-unos*)
 				vendor=crds
 				;;
-			-dgux*)
+			*-dgux*)
 				vendor=dg
 				;;
-			-luna*)
+			*-luna*)
 				vendor=omron
 				;;
-			-genix*)
+			*-genix*)
 				vendor=ns
 				;;
-			-mvs* | -opened*)
+			*-clix*)
+				vendor=intergraph
+				;;
+			*-mvs* | *-opened*)
 				vendor=ibm
 				;;
-			-os400*)
+			*-os400*)
 				vendor=ibm
 				;;
-			-ptx*)
+			s390-* | s390x-*)
+				vendor=ibm
+				;;
+			*-ptx*)
 				vendor=sequent
 				;;
-			-tpf*)
+			*-tpf*)
 				vendor=ibm
 				;;
-			-vxsim* | -vxworks* | -windiss*)
+			*-vxsim* | *-vxworks* | *-windiss*)
 				vendor=wrs
 				;;
-			-aux*)
+			*-aux*)
 				vendor=apple
 				;;
-			-hms*)
+			*-hms*)
 				vendor=hitachi
 				;;
-			-mpw* | -macos*)
+			*-mpw* | *-macos*)
 				vendor=apple
 				;;
-			-*mint | -mint[0-9]* | -*MiNT | -MiNT[0-9]*)
+			*-*mint | *-mint[0-9]* | *-*MiNT | *-MiNT[0-9]*)
 				vendor=atari
 				;;
-			-vos*)
+			*-vos*)
 				vendor=stratus
 				;;
 		esac
-		basic_machine=`echo "$basic_machine" | sed "s/unknown/$vendor/"`
 		;;
 esac
 
-echo "$basic_machine$os"
+echo "$cpu-$vendor${kernel:+-$kernel}${os:+-$os}${obj:+-$obj}"
 exit
 
 # Local variables:
diff --git a/configure b/configure
index 574bfae..7f3a0f8 100755
--- a/configure
+++ b/configure
@@ -1,11 +1,12 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for libpng 1.6.38.git.
+# Generated by GNU Autoconf 2.72 for libpng 1.6.43.git.
 #
 # Report bugs to <png-mng-implement@lists.sourceforge.net>.
 #
 #
-# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
+# Copyright (C) 1992-1996, 1998-2017, 2020-2023 Free Software Foundation,
+# Inc.
 #
 #
 # This configure script is free software; the Free Software Foundation
@@ -16,63 +17,65 @@
 
 # Be more Bourne compatible
 DUALCASE=1; export DUALCASE # for MKS sh
-if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then :
+if test ${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on ${1+"$@"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '${1+"$@"}'='"$@"'
   setopt NO_GLOB_SUBST
-else
-  case `(set -o) 2>/dev/null` in #(
+else case e in #(
+  e) case `(set -o) 2>/dev/null` in #(
   *posix*) :
     set -o posix ;; #(
   *) :
      ;;
+esac ;;
 esac
 fi
 
 
+
+# Reset variables that may have inherited troublesome values from
+# the environment.
+
+# IFS needs to be set, to space, tab, and newline, in precisely that order.
+# (If _AS_PATH_WALK were called with IFS unset, it would have the
+# side effect of setting IFS to empty, thus disabling word splitting.)
+# Quoting is to prevent editors from complaining about space-tab.
 as_nl='
 '
 export as_nl
-# Printing a long string crashes Solaris 7 /usr/bin/printf.
-as_echo='\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo$as_echo
-# Prefer a ksh shell builtin over an external printf program on Solaris,
-# but without wasting forks for bash or zsh.
-if test -z "$BASH_VERSION$ZSH_VERSION" \
-    && (test "X`print -r -- $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='print -r --'
-  as_echo_n='print -rn --'
-elif (test "X`printf %s $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='printf %s\n'
-  as_echo_n='printf %s'
-else
-  if test "X`(/usr/ucb/echo -n -n $as_echo) 2>/dev/null`" = "X-n $as_echo"; then
-    as_echo_body='eval /usr/ucb/echo -n "$1$as_nl"'
-    as_echo_n='/usr/ucb/echo -n'
-  else
-    as_echo_body='eval expr "X$1" : "X\\(.*\\)"'
-    as_echo_n_body='eval
-      arg=$1;
-      case $arg in #(
-      *"$as_nl"*)
-	expr "X$arg" : "X\\(.*\\)$as_nl";
-	arg=`expr "X$arg" : ".*$as_nl\\(.*\\)"`;;
-      esac;
-      expr "X$arg" : "X\\(.*\\)" | tr -d "$as_nl"
-    '
-    export as_echo_n_body
-    as_echo_n='sh -c $as_echo_n_body as_echo'
-  fi
-  export as_echo_body
-  as_echo='sh -c $as_echo_body as_echo'
-fi
+IFS=" ""	$as_nl"
+
+PS1='$ '
+PS2='> '
+PS4='+ '
+
+# Ensure predictable behavior from utilities with locale-dependent output.
+LC_ALL=C
+export LC_ALL
+LANGUAGE=C
+export LANGUAGE
+
+# We cannot yet rely on "unset" to work, but we need these variables
+# to be unset--not just set to an empty or harmless value--now, to
+# avoid bugs in old shells (e.g. pre-3.0 UWIN ksh).  This construct
+# also avoids known problems related to "unset" and subshell syntax
+# in other old shells (e.g. bash 2.01 and pdksh 5.2.14).
+for as_var in BASH_ENV ENV MAIL MAILPATH CDPATH
+do eval test \${$as_var+y} \
+  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
+done
+
+# Ensure that fds 0, 1, and 2 are open.
+if (exec 3>&0) 2>/dev/null; then :; else exec 0</dev/null; fi
+if (exec 3>&1) 2>/dev/null; then :; else exec 1>/dev/null; fi
+if (exec 3>&2)            ; then :; else exec 2>/dev/null; fi
 
 # The user is always right.
-if test "${PATH_SEPARATOR+set}" != set; then
+if ${PATH_SEPARATOR+false} :; then
   PATH_SEPARATOR=:
   (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 && {
     (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 ||
@@ -81,13 +84,6 @@
 fi
 
 
-# IFS
-# We need space, tab and new line, in precisely that order.  Quoting is
-# there to prevent editors from complaining about space-tab.
-# (If _AS_PATH_WALK were called with IFS unset, it would disable word
-# splitting by setting IFS to empty value.)
-IFS=" ""	$as_nl"
-
 # Find who we are.  Look in the path if we contain no directory separator.
 as_myself=
 case $0 in #((
@@ -96,43 +92,27 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    test -r "$as_dir/$0" && as_myself=$as_dir/$0 && break
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    test -r "$as_dir$0" && as_myself=$as_dir$0 && break
   done
 IFS=$as_save_IFS
 
      ;;
 esac
-# We did not find ourselves, most probably we were run as `sh COMMAND'
+# We did not find ourselves, most probably we were run as 'sh COMMAND'
 # in which case we are not to be found in the path.
 if test "x$as_myself" = x; then
   as_myself=$0
 fi
 if test ! -f "$as_myself"; then
-  $as_echo "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
+  printf "%s\n" "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
   exit 1
 fi
 
-# Unset variables that we do not need and which cause bugs (e.g. in
-# pre-3.0 UWIN ksh).  But do not cause bugs in bash 2.01; the "|| exit 1"
-# suppresses any "Segmentation fault" message there.  '((' could
-# trigger a bug in pdksh 5.2.14.
-for as_var in BASH_ENV ENV MAIL MAILPATH
-do eval test x\${$as_var+set} = xset \
-  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
-done
-PS1='$ '
-PS2='> '
-PS4='+ '
-
-# NLS nuisances.
-LC_ALL=C
-export LC_ALL
-LANGUAGE=C
-export LANGUAGE
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
 
 # Use a proper internal environment variable to ensure we don't fall
   # into an infinite loop, continuously re-executing ourselves.
@@ -153,26 +133,28 @@
 esac
 exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
 # Admittedly, this is quite paranoid, since all the known shells bail
-# out after a failed `exec'.
-$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
-as_fn_exit 255
+# out after a failed 'exec'.
+printf "%s\n" "$0: could not re-execute with $CONFIG_SHELL" >&2
+exit 255
   fi
   # We don't want this to propagate to other subprocesses.
           { _as_can_reexec=; unset _as_can_reexec;}
 if test "x$CONFIG_SHELL" = x; then
-  as_bourne_compatible="if test -n \"\${ZSH_VERSION+set}\" && (emulate sh) >/dev/null 2>&1; then :
+  as_bourne_compatible="if test \${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on \${1+\"\$@\"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '\${1+\"\$@\"}'='\"\$@\"'
   setopt NO_GLOB_SUBST
-else
-  case \`(set -o) 2>/dev/null\` in #(
+else case e in #(
+  e) case \`(set -o) 2>/dev/null\` in #(
   *posix*) :
     set -o posix ;; #(
   *) :
      ;;
+esac ;;
 esac
 fi
 "
@@ -187,12 +169,16 @@
 as_fn_failure && { exitcode=1; echo as_fn_failure succeeded.; }
 as_fn_ret_success || { exitcode=1; echo as_fn_ret_success failed.; }
 as_fn_ret_failure && { exitcode=1; echo as_fn_ret_failure succeeded.; }
-if ( set x; as_fn_ret_success y && test x = \"\$1\" ); then :
+if ( set x; as_fn_ret_success y && test x = \"\$1\" )
+then :
 
-else
-  exitcode=1; echo positional parameters were not saved.
+else case e in #(
+  e) exitcode=1; echo positional parameters were not saved. ;;
+esac
 fi
 test x\$exitcode = x0 || exit 1
+blah=\$(echo \$(echo blah))
+test x\"\$blah\" = xblah || exit 1
 test -x / || exit 1"
   as_suggested="  as_lineno_1=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_1a=\$LINENO
   as_lineno_2=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_2a=\$LINENO
@@ -207,30 +193,39 @@
     PATH=/empty FPATH=/empty; export PATH FPATH
     test \"X\`printf %s \$ECHO\`\" = \"X\$ECHO\" \\
       || test \"X\`print -r -- \$ECHO\`\" = \"X\$ECHO\" ) || exit 1"
-  if (eval "$as_required") 2>/dev/null; then :
+  if (eval "$as_required") 2>/dev/null
+then :
   as_have_required=yes
-else
-  as_have_required=no
+else case e in #(
+  e) as_have_required=no ;;
+esac
 fi
-  if test x$as_have_required = xyes && (eval "$as_suggested") 2>/dev/null; then :
+  if test x$as_have_required = xyes && (eval "$as_suggested") 2>/dev/null
+then :
 
-else
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+else case e in #(
+  e) as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 as_found=false
 for as_dir in /bin$PATH_SEPARATOR/usr/bin$PATH_SEPARATOR$PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
   as_found=:
   case $as_dir in #(
 	 /*)
 	   for as_base in sh bash ksh sh5; do
 	     # Try only shells that exist, to save several forks.
-	     as_shell=$as_dir/$as_base
+	     as_shell=$as_dir$as_base
 	     if { test -f "$as_shell" || test -f "$as_shell.exe"; } &&
-		    { $as_echo "$as_bourne_compatible""$as_required" | as_run=a "$as_shell"; } 2>/dev/null; then :
+		    as_run=a "$as_shell" -c "$as_bourne_compatible""$as_required" 2>/dev/null
+then :
   CONFIG_SHELL=$as_shell as_have_required=yes
-		   if { $as_echo "$as_bourne_compatible""$as_suggested" | as_run=a "$as_shell"; } 2>/dev/null; then :
+		   if as_run=a "$as_shell" -c "$as_bourne_compatible""$as_suggested" 2>/dev/null
+then :
   break 2
 fi
 fi
@@ -238,14 +233,22 @@
        esac
   as_found=false
 done
-$as_found || { if { test -f "$SHELL" || test -f "$SHELL.exe"; } &&
-	      { $as_echo "$as_bourne_compatible""$as_required" | as_run=a "$SHELL"; } 2>/dev/null; then :
-  CONFIG_SHELL=$SHELL as_have_required=yes
-fi; }
 IFS=$as_save_IFS
+if $as_found
+then :
+
+else case e in #(
+  e) if { test -f "$SHELL" || test -f "$SHELL.exe"; } &&
+	      as_run=a "$SHELL" -c "$as_bourne_compatible""$as_required" 2>/dev/null
+then :
+  CONFIG_SHELL=$SHELL as_have_required=yes
+fi ;;
+esac
+fi
 
 
-      if test "x$CONFIG_SHELL" != x; then :
+      if test "x$CONFIG_SHELL" != x
+then :
   export CONFIG_SHELL
              # We cannot yet assume a decent shell, so we have to provide a
 # neutralization value for shells without unset; and this also
@@ -262,26 +265,28 @@
 esac
 exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
 # Admittedly, this is quite paranoid, since all the known shells bail
-# out after a failed `exec'.
-$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
+# out after a failed 'exec'.
+printf "%s\n" "$0: could not re-execute with $CONFIG_SHELL" >&2
 exit 255
 fi
 
-    if test x$as_have_required = xno; then :
-  $as_echo "$0: This script requires a shell more modern than all"
-  $as_echo "$0: the shells that I found on your system."
-  if test x${ZSH_VERSION+set} = xset ; then
-    $as_echo "$0: In particular, zsh $ZSH_VERSION has bugs and should"
-    $as_echo "$0: be upgraded to zsh 4.3.4 or later."
+    if test x$as_have_required = xno
+then :
+  printf "%s\n" "$0: This script requires a shell more modern than all"
+  printf "%s\n" "$0: the shells that I found on your system."
+  if test ${ZSH_VERSION+y} ; then
+    printf "%s\n" "$0: In particular, zsh $ZSH_VERSION has bugs and should"
+    printf "%s\n" "$0: be upgraded to zsh 4.3.4 or later."
   else
-    $as_echo "$0: Please tell bug-autoconf@gnu.org and
+    printf "%s\n" "$0: Please tell bug-autoconf@gnu.org and
 $0: png-mng-implement@lists.sourceforge.net about your
 $0: system, including any error possibly output before this
 $0: message. Then install a modern shell, or manually run
 $0: the script under such a shell if you do have one."
   fi
   exit 1
-fi
+fi ;;
+esac
 fi
 fi
 SHELL=${CONFIG_SHELL-/bin/sh}
@@ -302,6 +307,7 @@
 }
 as_unset=as_fn_unset
 
+
 # as_fn_set_status STATUS
 # -----------------------
 # Set $? to STATUS, without forking.
@@ -333,7 +339,7 @@
     as_dirs=
     while :; do
       case $as_dir in #(
-      *\'*) as_qdir=`$as_echo "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
+      *\'*) as_qdir=`printf "%s\n" "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
       *) as_qdir=$as_dir;;
       esac
       as_dirs="'$as_qdir' $as_dirs"
@@ -342,7 +348,7 @@
 	 X"$as_dir" : 'X\(//\)[^/]' \| \
 	 X"$as_dir" : 'X\(//\)$' \| \
 	 X"$as_dir" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_dir" |
+printf "%s\n" X"$as_dir" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -381,16 +387,18 @@
 # advantage of any shell optimizations that allow amortized linear growth over
 # repeated appends, instead of the typical quadratic growth present in naive
 # implementations.
-if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null; then :
+if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null
+then :
   eval 'as_fn_append ()
   {
     eval $1+=\$2
   }'
-else
-  as_fn_append ()
+else case e in #(
+  e) as_fn_append ()
   {
     eval $1=\$$1\$2
-  }
+  } ;;
+esac
 fi # as_fn_append
 
 # as_fn_arith ARG...
@@ -398,16 +406,18 @@
 # Perform arithmetic evaluation on the ARGs, and store the result in the
 # global $as_val. Take advantage of shells that can avoid forks. The arguments
 # must be portable across $(()) and expr.
-if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null; then :
+if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null
+then :
   eval 'as_fn_arith ()
   {
     as_val=$(( $* ))
   }'
-else
-  as_fn_arith ()
+else case e in #(
+  e) as_fn_arith ()
   {
     as_val=`expr "$@" || test $? -eq 1`
-  }
+  } ;;
+esac
 fi # as_fn_arith
 
 
@@ -421,9 +431,9 @@
   as_status=$1; test $as_status -eq 0 && as_status=1
   if test "$4"; then
     as_lineno=${as_lineno-"$3"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-    $as_echo "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
   fi
-  $as_echo "$as_me: error: $2" >&2
+  printf "%s\n" "$as_me: error: $2" >&2
   as_fn_exit $as_status
 } # as_fn_error
 
@@ -450,7 +460,7 @@
 $as_expr X/"$0" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$0" : 'X\(//\)$' \| \
 	 X"$0" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$0" |
+printf "%s\n" X/"$0" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -483,6 +493,8 @@
     /[$]LINENO/=
   ' <$as_myself |
     sed '
+      t clear
+      :clear
       s/[$]LINENO.*/&-/
       t lineno
       b
@@ -494,7 +506,7 @@
       s/-\n.*//
     ' >$as_me.lineno &&
   chmod +x "$as_me.lineno" ||
-    { $as_echo "$as_me: error: cannot create $as_me.lineno; rerun with a POSIX shell" >&2; as_fn_exit 1; }
+    { printf "%s\n" "$as_me: error: cannot create $as_me.lineno; rerun with a POSIX shell" >&2; as_fn_exit 1; }
 
   # If we had to re-execute with $CONFIG_SHELL, we're ensured to have
   # already done that, so ensure we don't try to do so again and fall
@@ -508,6 +520,10 @@
   exit
 }
 
+
+# Determine whether it's possible to make 'echo' print without a newline.
+# These variables are no longer used directly by Autoconf, but are AC_SUBSTed
+# for compatibility with existing Makefiles.
 ECHO_C= ECHO_N= ECHO_T=
 case `echo -n x` in #(((((
 -n*)
@@ -521,6 +537,12 @@
   ECHO_N='-n';;
 esac
 
+# For backward compatibility with old third-party macros, we provide
+# the shell variables $as_echo and $as_echo_n.  New code should use
+# AS_ECHO(["message"]) and AS_ECHO_N(["message"]), respectively.
+as_echo='printf %s\n'
+as_echo_n='printf %s'
+
 rm -f conf$$ conf$$.exe conf$$.file
 if test -d conf$$.dir; then
   rm -f conf$$.dir/conf$$.file
@@ -532,9 +554,9 @@
   if ln -s conf$$.file conf$$ 2>/dev/null; then
     as_ln_s='ln -s'
     # ... but there are two gotchas:
-    # 1) On MSYS, both `ln -s file dir' and `ln file dir' fail.
-    # 2) DJGPP < 2.04 has no symlinks; `ln -s' creates a wrapper executable.
-    # In both cases, we have to default to `cp -pR'.
+    # 1) On MSYS, both 'ln -s file dir' and 'ln file dir' fail.
+    # 2) DJGPP < 2.04 has no symlinks; 'ln -s' creates a wrapper executable.
+    # In both cases, we have to default to 'cp -pR'.
     ln -s conf$$.file conf$$.dir 2>/dev/null && test ! -f conf$$.exe ||
       as_ln_s='cp -pR'
   elif ln conf$$.file conf$$ 2>/dev/null; then
@@ -559,10 +581,12 @@
 as_executable_p=as_fn_executable_p
 
 # Sed expression to map a string onto a valid CPP name.
-as_tr_cpp="eval sed 'y%*$as_cr_letters%P$as_cr_LETTERS%;s%[^_$as_cr_alnum]%_%g'"
+as_sed_cpp="y%*$as_cr_letters%P$as_cr_LETTERS%;s%[^_$as_cr_alnum]%_%g"
+as_tr_cpp="eval sed '$as_sed_cpp'" # deprecated
 
 # Sed expression to map a string onto a valid variable name.
-as_tr_sh="eval sed 'y%*+%pp%;s%[^_$as_cr_alnum]%_%g'"
+as_sed_sh="y%*+%pp%;s%[^_$as_cr_alnum]%_%g"
+as_tr_sh="eval sed '$as_sed_sh'" # deprecated
 
 SHELL=${CONFIG_SHELL-/bin/sh}
 
@@ -590,55 +614,56 @@
 # Identity of this package.
 PACKAGE_NAME='libpng'
 PACKAGE_TARNAME='libpng'
-PACKAGE_VERSION='1.6.38.git'
-PACKAGE_STRING='libpng 1.6.38.git'
+PACKAGE_VERSION='1.6.43.git'
+PACKAGE_STRING='libpng 1.6.43.git'
 PACKAGE_BUGREPORT='png-mng-implement@lists.sourceforge.net'
 PACKAGE_URL=''
 
 ac_unique_file="pngget.c"
 # Factoring default headers for most tests.
 ac_includes_default="\
-#include <stdio.h>
-#ifdef HAVE_SYS_TYPES_H
-# include <sys/types.h>
+#include <stddef.h>
+#ifdef HAVE_STDIO_H
+# include <stdio.h>
 #endif
-#ifdef HAVE_SYS_STAT_H
-# include <sys/stat.h>
-#endif
-#ifdef STDC_HEADERS
+#ifdef HAVE_STDLIB_H
 # include <stdlib.h>
-# include <stddef.h>
-#else
-# ifdef HAVE_STDLIB_H
-#  include <stdlib.h>
-# endif
 #endif
 #ifdef HAVE_STRING_H
-# if !defined STDC_HEADERS && defined HAVE_MEMORY_H
-#  include <memory.h>
-# endif
 # include <string.h>
 #endif
-#ifdef HAVE_STRINGS_H
-# include <strings.h>
-#endif
 #ifdef HAVE_INTTYPES_H
 # include <inttypes.h>
 #endif
 #ifdef HAVE_STDINT_H
 # include <stdint.h>
 #endif
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
 #ifdef HAVE_UNISTD_H
 # include <unistd.h>
 #endif"
 
+ac_header_c_list=
 ac_subst_vars='am__EXEEXT_FALSE
 am__EXEEXT_TRUE
 LTLIBOBJS
+LIBOBJS
+PNG_LOONGARCH_LSX_FALSE
+PNG_LOONGARCH_LSX_TRUE
 PNG_POWERPC_VSX_FALSE
 PNG_POWERPC_VSX_TRUE
 PNG_INTEL_SSE_FALSE
 PNG_INTEL_SSE_TRUE
+PNG_MIPS_MMI_FALSE
+PNG_MIPS_MMI_TRUE
 PNG_MIPS_MSA_FALSE
 PNG_MIPS_MSA_TRUE
 PNG_ARM_NEON_FALSE
@@ -665,9 +690,11 @@
 HAVE_SOLARIS_LD_TRUE
 HAVE_CLOCK_GETTIME_FALSE
 HAVE_CLOCK_GETTIME_TRUE
-LIBOBJS
-POW_LIB
 PNG_COPTS
+ENABLE_TOOLS_FALSE
+ENABLE_TOOLS_TRUE
+ENABLE_TESTS_FALSE
+ENABLE_TESTS_TRUE
 DFNCPP
 LT_SYS_LIBRARY_PATH
 OTOOL64
@@ -679,6 +706,7 @@
 RANLIB
 ac_ct_AR
 AR
+FILECMD
 NM
 ac_ct_DUMPBIN
 DUMPBIN
@@ -729,6 +757,9 @@
 AM_DEFAULT_VERBOSITY
 AM_DEFAULT_V
 AM_V
+CSCOPE
+ETAGS
+CTAGS
 am__untar
 am__tar
 AMTAR
@@ -771,6 +802,7 @@
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -805,6 +837,8 @@
 with_aix_soname
 with_sysroot
 enable_libtool_lock
+enable_tests
+enable_tools
 enable_werror
 with_zlib_prefix
 with_pkgconfigdir
@@ -816,8 +850,10 @@
 enable_hardware_optimizations
 enable_arm_neon
 enable_mips_msa
+enable_mips_mmi
 enable_intel_sse
 enable_powerpc_vsx
+enable_loongarch_lsx
 '
       ac_precious_vars='build_alias
 host_alias
@@ -870,6 +906,7 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -899,8 +936,6 @@
   *)    ac_optarg=yes ;;
   esac
 
-  # Accept the important Cygnus configure options, so we can diagnose typos.
-
   case $ac_dashdash$ac_option in
   --)
     ac_dashdash=yes ;;
@@ -941,9 +976,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*disable-\(.*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid feature name: $ac_useropt"
+      as_fn_error $? "invalid feature name: '$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "enable_$ac_useropt"
@@ -967,9 +1002,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*enable-\([^=]*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid feature name: $ac_useropt"
+      as_fn_error $? "invalid feature name: '$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "enable_$ac_useropt"
@@ -1122,6 +1157,15 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1171,9 +1215,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*with-\([^=]*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid package name: $ac_useropt"
+      as_fn_error $? "invalid package name: '$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "with_$ac_useropt"
@@ -1187,9 +1231,9 @@
     ac_useropt=`expr "x$ac_option" : 'x-*without-\(.*\)'`
     # Reject names that are not valid shell variable names.
     expr "x$ac_useropt" : ".*[^-+._$as_cr_alnum]" >/dev/null &&
-      as_fn_error $? "invalid package name: $ac_useropt"
+      as_fn_error $? "invalid package name: '$ac_useropt'"
     ac_useropt_orig=$ac_useropt
-    ac_useropt=`$as_echo "$ac_useropt" | sed 's/[-+.]/_/g'`
+    ac_useropt=`printf "%s\n" "$ac_useropt" | sed 's/[-+.]/_/g'`
     case $ac_user_opts in
       *"
 "with_$ac_useropt"
@@ -1217,8 +1261,8 @@
   | --x-librar=* | --x-libra=* | --x-libr=* | --x-lib=* | --x-li=* | --x-l=*)
     x_libraries=$ac_optarg ;;
 
-  -*) as_fn_error $? "unrecognized option: \`$ac_option'
-Try \`$0 --help' for more information"
+  -*) as_fn_error $? "unrecognized option: '$ac_option'
+Try '$0 --help' for more information"
     ;;
 
   *=*)
@@ -1226,16 +1270,16 @@
     # Reject names that are not valid shell variable names.
     case $ac_envvar in #(
       '' | [0-9]* | *[!_$as_cr_alnum]* )
-      as_fn_error $? "invalid variable name: \`$ac_envvar'" ;;
+      as_fn_error $? "invalid variable name: '$ac_envvar'" ;;
     esac
     eval $ac_envvar=\$ac_optarg
     export $ac_envvar ;;
 
   *)
     # FIXME: should be removed in autoconf 3.0.
-    $as_echo "$as_me: WARNING: you should use --build, --host, --target" >&2
+    printf "%s\n" "$as_me: WARNING: you should use --build, --host, --target" >&2
     expr "x$ac_option" : ".*[^-._$as_cr_alnum]" >/dev/null &&
-      $as_echo "$as_me: WARNING: invalid host type: $ac_option" >&2
+      printf "%s\n" "$as_me: WARNING: invalid host type: $ac_option" >&2
     : "${build_alias=$ac_option} ${host_alias=$ac_option} ${target_alias=$ac_option}"
     ;;
 
@@ -1251,7 +1295,7 @@
   case $enable_option_checking in
     no) ;;
     fatal) as_fn_error $? "unrecognized options: $ac_unrecognized_opts" ;;
-    *)     $as_echo "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2 ;;
+    *)     printf "%s\n" "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2 ;;
   esac
 fi
 
@@ -1259,7 +1303,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1276,7 +1320,7 @@
   as_fn_error $? "expected an absolute directory name for --$ac_var: $ac_val"
 done
 
-# There might be people who depend on the old broken behavior: `$host'
+# There might be people who depend on the old broken behavior: '$host'
 # used to hold the argument of --host etc.
 # FIXME: To remove some day.
 build=$build_alias
@@ -1315,7 +1359,7 @@
 	 X"$as_myself" : 'X\(//\)[^/]' \| \
 	 X"$as_myself" : 'X\(//\)$' \| \
 	 X"$as_myself" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_myself" |
+printf "%s\n" X"$as_myself" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -1344,7 +1388,7 @@
   test "$ac_srcdir_defaulted" = yes && srcdir="$ac_confdir or .."
   as_fn_error $? "cannot find sources ($ac_unique_file) in $srcdir"
 fi
-ac_msg="sources are in $srcdir, but \`cd $srcdir' does not work"
+ac_msg="sources are in $srcdir, but 'cd $srcdir' does not work"
 ac_abs_confdir=`(
 	cd "$srcdir" && test -r "./$ac_unique_file" || as_fn_error $? "$ac_msg"
 	pwd)`
@@ -1372,7 +1416,7 @@
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures libpng 1.6.38.git to adapt to many kinds of systems.
+'configure' configures libpng 1.6.43.git to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1386,11 +1430,11 @@
       --help=short        display options specific to this package
       --help=recursive    display the short help of all the included packages
   -V, --version           display version information and exit
-  -q, --quiet, --silent   do not print \`checking ...' messages
+  -q, --quiet, --silent   do not print 'checking ...' messages
       --cache-file=FILE   cache test results in FILE [disabled]
-  -C, --config-cache      alias for \`--cache-file=config.cache'
+  -C, --config-cache      alias for '--cache-file=config.cache'
   -n, --no-create         do not create output files
-      --srcdir=DIR        find the sources in DIR [configure dir or \`..']
+      --srcdir=DIR        find the sources in DIR [configure dir or '..']
 
 Installation directories:
   --prefix=PREFIX         install architecture-independent files in PREFIX
@@ -1398,10 +1442,10 @@
   --exec-prefix=EPREFIX   install architecture-dependent files in EPREFIX
                           [PREFIX]
 
-By default, \`make install' will install all the files in
-\`$ac_default_prefix/bin', \`$ac_default_prefix/lib' etc.  You can specify
-an installation prefix other than \`$ac_default_prefix' using \`--prefix',
-for instance \`--prefix=\$HOME'.
+By default, 'make install' will install all the files in
+'$ac_default_prefix/bin', '$ac_default_prefix/lib' etc.  You can specify
+an installation prefix other than '$ac_default_prefix' using '--prefix',
+for instance '--prefix=\$HOME'.
 
 For better control, use the options below.
 
@@ -1412,6 +1456,7 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -1442,7 +1487,7 @@
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of libpng 1.6.38.git:";;
+     short | recursive ) echo "Configuration of libpng 1.6.43.git:";;
    esac
   cat <<\_ACEOF
 
@@ -1464,6 +1509,9 @@
   --enable-fast-install[=PKGS]
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
+  --disable-tests         do not build the test programs (default is to build)
+  --disable-tools         do not build the auxiliary tools (default is to
+                          build)
   --enable-werror[=OPT] Pass -Werror or the given argument to the compiler
                           if it is supported
   --enable-unversioned-links
@@ -1510,6 +1558,13 @@
                           call to png_set_option; yes/on: turn on
                           unconditionally. If not specified: determined by the
                           compiler.
+  --enable-mips-mmi     Enable MIPS MMI optimizations: =no/off, check, api,
+                          yes/on: no/off: disable the optimizations; check:
+                          use internal checking code (deprecated and poorly
+                          supported); api: disable by default, enable by a
+                          call to png_set_option; yes/on: turn on
+                          unconditionally. If not specified: determined by the
+                          compiler.
   --enable-intel-sse    Enable Intel SSE optimizations: =no/off, yes/on:
                           no/off: disable the optimizations; yes/on: enable
                           the optimizations. If not specified: determined by
@@ -1520,6 +1575,11 @@
                           default, enable by a call to png_set_option yes/on:
                           turn on unconditionally. If not specified:
                           determined by the compiler.
+  --enable-loongarch-lsx
+                          Enable LOONGARCH LSX optimizations: =no/off, yes/on:
+                          no/off: disable the optimizations; yes/on: turn on
+                          unconditionally. If not specified: determined by the
+                          compiler.
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
@@ -1556,7 +1616,7 @@
   PNG_COPTS   additional flags for the C compiler, use this for options that
               would cause configure itself to fail
 
-Use these variables to override the choices made by `configure' or to help
+Use these variables to override the choices made by 'configure' or to help
 it to find libraries and programs with nonstandard names/locations.
 
 Report bugs to <png-mng-implement@lists.sourceforge.net>.
@@ -1575,9 +1635,9 @@
 case "$ac_dir" in
 .) ac_dir_suffix= ac_top_builddir_sub=. ac_top_build_prefix= ;;
 *)
-  ac_dir_suffix=/`$as_echo "$ac_dir" | sed 's|^\.[\\/]||'`
+  ac_dir_suffix=/`printf "%s\n" "$ac_dir" | sed 's|^\.[\\/]||'`
   # A ".." for each directory in $ac_dir_suffix.
-  ac_top_builddir_sub=`$as_echo "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
+  ac_top_builddir_sub=`printf "%s\n" "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
   case $ac_top_builddir_sub in
   "") ac_top_builddir_sub=. ac_top_build_prefix= ;;
   *)  ac_top_build_prefix=$ac_top_builddir_sub/ ;;
@@ -1605,7 +1665,8 @@
 ac_abs_srcdir=$ac_abs_top_srcdir$ac_dir_suffix
 
     cd "$ac_dir" || { ac_status=$?; continue; }
-    # Check for guested configure.
+    # Check for configure.gnu first; this name is used for a wrapper for
+    # Metaconfig's "Configure" on case-insensitive file systems.
     if test -f "$ac_srcdir/configure.gnu"; then
       echo &&
       $SHELL "$ac_srcdir/configure.gnu" --help=recursive
@@ -1613,7 +1674,7 @@
       echo &&
       $SHELL "$ac_srcdir/configure" --help=recursive
     else
-      $as_echo "$as_me: WARNING: no configuration information is in $ac_dir" >&2
+      printf "%s\n" "$as_me: WARNING: no configuration information is in $ac_dir" >&2
     fi || ac_status=$?
     cd "$ac_pwd" || { ac_status=$?; break; }
   done
@@ -1622,10 +1683,10 @@
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-libpng configure 1.6.38.git
-generated by GNU Autoconf 2.69
+libpng configure 1.6.43.git
+generated by GNU Autoconf 2.72
 
-Copyright (C) 2012 Free Software Foundation, Inc.
+Copyright (C) 2023 Free Software Foundation, Inc.
 This configure script is free software; the Free Software Foundation
 gives unlimited permission to copy, distribute and modify it.
 _ACEOF
@@ -1642,14 +1703,14 @@
 ac_fn_c_try_compile ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  rm -f conftest.$ac_objext
+  rm -f conftest.$ac_objext conftest.beam
   if { { ac_try="$ac_compile"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compile") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1657,17 +1718,19 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       } && test -s conftest.$ac_objext; then :
+       } && test -s conftest.$ac_objext
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else case e in #(
+  e) printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	ac_retval=1
+	ac_retval=1 ;;
+esac
 fi
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
   as_fn_set_status $ac_retval
@@ -1686,7 +1749,7 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_cpp conftest.$ac_ext") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1694,17 +1757,19 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } > conftest.i && {
 	 test -z "$ac_c_preproc_warn_flag$ac_c_werror_flag" ||
 	 test ! -s conftest.err
-       }; then :
+       }
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else case e in #(
+  e) printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-    ac_retval=1
+    ac_retval=1 ;;
+esac
 fi
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
   as_fn_set_status $ac_retval
@@ -1717,14 +1782,14 @@
 ac_fn_c_try_link ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  rm -f conftest.$ac_objext conftest$ac_exeext
+  rm -f conftest.$ac_objext conftest.beam conftest$ac_exeext
   if { { ac_try="$ac_link"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -1732,20 +1797,22 @@
     cat conftest.er1 >&5
     mv -f conftest.er1 conftest.err
   fi
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && {
 	 test -z "$ac_c_werror_flag" ||
 	 test ! -s conftest.err
        } && test -s conftest$ac_exeext && {
 	 test "$cross_compiling" = yes ||
 	 test -x conftest$ac_exeext
-       }; then :
+       }
+then :
   ac_retval=0
-else
-  $as_echo "$as_me: failed program was:" >&5
+else case e in #(
+  e) printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-	ac_retval=1
+	ac_retval=1 ;;
+esac
 fi
   # Delete the IPA/IPO (Inter Procedural Analysis/Optimization) information
   # created by the PGI compiler (conftest_ipa8_conftest.oo), as it would
@@ -1764,100 +1831,56 @@
 ac_fn_c_check_header_compile ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
+printf %s "checking for $2... " >&6; }
+if eval test \${$3+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 $4
 #include <$2>
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   eval "$3=yes"
-else
-  eval "$3=no"
+else case e in #(
+  e) eval "$3=no" ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
+esac
 fi
 eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_check_header_compile
 
-# ac_fn_c_try_run LINENO
-# ----------------------
-# Try to link conftest.$ac_ext, and return whether this succeeded. Assumes
-# that executables *can* be run.
-ac_fn_c_try_run ()
-{
-  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  if { { ac_try="$ac_link"
-case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
-  (eval "$ac_link") 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; } && { ac_try='./conftest$ac_exeext'
-  { { case "(($ac_try" in
-  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
-  *) ac_try_echo=$ac_try;;
-esac
-eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
-  (eval "$ac_try") 2>&5
-  ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; }; then :
-  ac_retval=0
-else
-  $as_echo "$as_me: program exited with status $ac_status" >&5
-       $as_echo "$as_me: failed program was:" >&5
-sed 's/^/| /' conftest.$ac_ext >&5
-
-       ac_retval=$ac_status
-fi
-  rm -rf conftest.dSYM conftest_ipa8_conftest.oo
-  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
-  as_fn_set_status $ac_retval
-
-} # ac_fn_c_try_run
-
 # ac_fn_c_check_func LINENO FUNC VAR
 # ----------------------------------
 # Tests whether FUNC exists, setting the cache variable VAR accordingly
 ac_fn_c_check_func ()
 {
   as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
+printf %s "checking for $2... " >&6; }
+if eval test \${$3+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 /* Define $2 to an innocuous variant, in case <limits.h> declares $2.
    For example, HP-UX 11i <limits.h> declares gettimeofday.  */
 #define $2 innocuous_$2
 
 /* System header to define __stub macros and hopefully few prototypes,
-    which can conflict with char $2 (); below.
-    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-    <limits.h> exists even on freestanding compilers.  */
+   which can conflict with char $2 (void); below.  */
 
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
-
+#include <limits.h>
 #undef $2
 
 /* Override any GCC internal prototype to avoid an error.
@@ -1866,7 +1889,7 @@
 #ifdef __cplusplus
 extern "C"
 #endif
-char $2 ();
+char $2 (void);
 /* The GNU C library defines this for functions which it implements
     to always fail with ENOSYS.  Some functions are actually named
     something starting with __ and the normal name is an alias.  */
@@ -1875,89 +1898,58 @@
 #endif
 
 int
-main ()
+main (void)
 {
 return $2 ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   eval "$3=yes"
-else
-  eval "$3=no"
+else case e in #(
+  e) eval "$3=no" ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
+    conftest$ac_exeext conftest.$ac_ext ;;
+esac
 fi
 eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
   eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
 
 } # ac_fn_c_check_func
+ac_configure_args_raw=
+for ac_arg
+do
+  case $ac_arg in
+  *\'*)
+    ac_arg=`printf "%s\n" "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
+  esac
+  as_fn_append ac_configure_args_raw " '$ac_arg'"
+done
 
-# ac_fn_c_check_type LINENO TYPE VAR INCLUDES
-# -------------------------------------------
-# Tests whether TYPE exists after having included INCLUDES, setting cache
-# variable VAR accordingly.
-ac_fn_c_check_type ()
-{
-  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
-$as_echo_n "checking for $2... " >&6; }
-if eval \${$3+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  eval "$3=no"
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-$4
-int
-main ()
-{
-if (sizeof ($2))
-	 return 0;
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-$4
-int
-main ()
-{
-if (sizeof (($2)))
-	    return 0;
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+case $ac_configure_args_raw in
+  *$as_nl*)
+    ac_safe_unquote= ;;
+  *)
+    ac_unsafe_z='|&;<>()$`\\"*?[ ''	' # This string ends in space, tab.
+    ac_unsafe_a="$ac_unsafe_z#~"
+    ac_safe_unquote="s/ '\\([^$ac_unsafe_a][^$ac_unsafe_z]*\\)'/ \\1/g"
+    ac_configure_args_raw=`      printf "%s\n" "$ac_configure_args_raw" | sed "$ac_safe_unquote"`;;
+esac
 
-else
-  eval "$3=yes"
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-eval ac_res=\$$3
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
-
-} # ac_fn_c_check_type
 cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by libpng $as_me 1.6.38.git, which was
-generated by GNU Autoconf 2.69.  Invocation command line was
+It was created by libpng $as_me 1.6.43.git, which was
+generated by GNU Autoconf 2.72.  Invocation command line was
 
-  $ $0 $@
+  $ $0$ac_configure_args_raw
 
 _ACEOF
 exec 5>>config.log
@@ -1990,8 +1982,12 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    $as_echo "PATH: $as_dir"
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    printf "%s\n" "PATH: $as_dir"
   done
 IFS=$as_save_IFS
 
@@ -2026,7 +2022,7 @@
     | -silent | --silent | --silen | --sile | --sil)
       continue ;;
     *\'*)
-      ac_arg=`$as_echo "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
+      ac_arg=`printf "%s\n" "$ac_arg" | sed "s/'/'\\\\\\\\''/g"` ;;
     esac
     case $ac_pass in
     1) as_fn_append ac_configure_args0 " '$ac_arg'" ;;
@@ -2061,11 +2057,13 @@
 # WARNING: Use '\'' to represent an apostrophe within the trap.
 # WARNING: Do not start the trap code with a newline, due to a FreeBSD 4.0 bug.
 trap 'exit_status=$?
+  # Sanitize IFS.
+  IFS=" ""	$as_nl"
   # Save into config.log some information that might help in debugging.
   {
     echo
 
-    $as_echo "## ---------------- ##
+    printf "%s\n" "## ---------------- ##
 ## Cache variables. ##
 ## ---------------- ##"
     echo
@@ -2076,8 +2074,8 @@
     case $ac_val in #(
     *${as_nl}*)
       case $ac_var in #(
-      *_cv_*) { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
-$as_echo "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
+      *_cv_*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
+printf "%s\n" "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
       esac
       case $ac_var in #(
       _ | IFS | as_nl) ;; #(
@@ -2101,7 +2099,7 @@
 )
     echo
 
-    $as_echo "## ----------------- ##
+    printf "%s\n" "## ----------------- ##
 ## Output variables. ##
 ## ----------------- ##"
     echo
@@ -2109,14 +2107,14 @@
     do
       eval ac_val=\$$ac_var
       case $ac_val in
-      *\'\''*) ac_val=`$as_echo "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
+      *\'\''*) ac_val=`printf "%s\n" "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
       esac
-      $as_echo "$ac_var='\''$ac_val'\''"
+      printf "%s\n" "$ac_var='\''$ac_val'\''"
     done | sort
     echo
 
     if test -n "$ac_subst_files"; then
-      $as_echo "## ------------------- ##
+      printf "%s\n" "## ------------------- ##
 ## File substitutions. ##
 ## ------------------- ##"
       echo
@@ -2124,15 +2122,15 @@
       do
 	eval ac_val=\$$ac_var
 	case $ac_val in
-	*\'\''*) ac_val=`$as_echo "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
+	*\'\''*) ac_val=`printf "%s\n" "$ac_val" | sed "s/'\''/'\''\\\\\\\\'\'''\''/g"`;;
 	esac
-	$as_echo "$ac_var='\''$ac_val'\''"
+	printf "%s\n" "$ac_var='\''$ac_val'\''"
       done | sort
       echo
     fi
 
     if test -s confdefs.h; then
-      $as_echo "## ----------- ##
+      printf "%s\n" "## ----------- ##
 ## confdefs.h. ##
 ## ----------- ##"
       echo
@@ -2140,8 +2138,8 @@
       echo
     fi
     test "$ac_signal" != 0 &&
-      $as_echo "$as_me: caught signal $ac_signal"
-    $as_echo "$as_me: exit $exit_status"
+      printf "%s\n" "$as_me: caught signal $ac_signal"
+    printf "%s\n" "$as_me: exit $exit_status"
   } >&5
   rm -f core *.core core.conftest.* &&
     rm -f -r conftest* confdefs* conf$$* $ac_clean_files &&
@@ -2155,65 +2153,50 @@
 # confdefs.h avoids OS command line length limits that DEFS can exceed.
 rm -f -r conftest* confdefs.h
 
-$as_echo "/* confdefs.h */" > confdefs.h
+printf "%s\n" "/* confdefs.h */" > confdefs.h
 
 # Predefined preprocessor variables.
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_NAME "$PACKAGE_NAME"
-_ACEOF
+printf "%s\n" "#define PACKAGE_NAME \"$PACKAGE_NAME\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_TARNAME "$PACKAGE_TARNAME"
-_ACEOF
+printf "%s\n" "#define PACKAGE_TARNAME \"$PACKAGE_TARNAME\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_VERSION "$PACKAGE_VERSION"
-_ACEOF
+printf "%s\n" "#define PACKAGE_VERSION \"$PACKAGE_VERSION\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_STRING "$PACKAGE_STRING"
-_ACEOF
+printf "%s\n" "#define PACKAGE_STRING \"$PACKAGE_STRING\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_BUGREPORT "$PACKAGE_BUGREPORT"
-_ACEOF
+printf "%s\n" "#define PACKAGE_BUGREPORT \"$PACKAGE_BUGREPORT\"" >>confdefs.h
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE_URL "$PACKAGE_URL"
-_ACEOF
+printf "%s\n" "#define PACKAGE_URL \"$PACKAGE_URL\"" >>confdefs.h
 
 
 # Let the site file select an alternate cache file if it wants to.
 # Prefer an explicitly selected file to automatically selected ones.
-ac_site_file1=NONE
-ac_site_file2=NONE
 if test -n "$CONFIG_SITE"; then
-  # We do not want a PATH search for config.site.
-  case $CONFIG_SITE in #((
-    -*)  ac_site_file1=./$CONFIG_SITE;;
-    */*) ac_site_file1=$CONFIG_SITE;;
-    *)   ac_site_file1=./$CONFIG_SITE;;
-  esac
+  ac_site_files="$CONFIG_SITE"
 elif test "x$prefix" != xNONE; then
-  ac_site_file1=$prefix/share/config.site
-  ac_site_file2=$prefix/etc/config.site
+  ac_site_files="$prefix/share/config.site $prefix/etc/config.site"
 else
-  ac_site_file1=$ac_default_prefix/share/config.site
-  ac_site_file2=$ac_default_prefix/etc/config.site
+  ac_site_files="$ac_default_prefix/share/config.site $ac_default_prefix/etc/config.site"
 fi
-for ac_site_file in "$ac_site_file1" "$ac_site_file2"
+
+for ac_site_file in $ac_site_files
 do
-  test "x$ac_site_file" = xNONE && continue
-  if test /dev/null != "$ac_site_file" && test -r "$ac_site_file"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: loading site script $ac_site_file" >&5
-$as_echo "$as_me: loading site script $ac_site_file" >&6;}
+  case $ac_site_file in #(
+  */*) :
+     ;; #(
+  *) :
+    ac_site_file=./$ac_site_file ;;
+esac
+  if test -f "$ac_site_file" && test -r "$ac_site_file"; then
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: loading site script $ac_site_file" >&5
+printf "%s\n" "$as_me: loading site script $ac_site_file" >&6;}
     sed 's/^/| /' "$ac_site_file" >&5
     . "$ac_site_file" \
-      || { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+      || { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "failed to load site script $ac_site_file
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; }
   fi
 done
 
@@ -2221,19 +2204,452 @@
   # Some versions of bash will fail to source /dev/null (special files
   # actually), so we avoid doing that.  DJGPP emulates it as a regular file.
   if test /dev/null != "$cache_file" && test -f "$cache_file"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: loading cache $cache_file" >&5
-$as_echo "$as_me: loading cache $cache_file" >&6;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: loading cache $cache_file" >&5
+printf "%s\n" "$as_me: loading cache $cache_file" >&6;}
     case $cache_file in
       [\\/]* | ?:[\\/]* ) . "$cache_file";;
       *)                      . "./$cache_file";;
     esac
   fi
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: creating cache $cache_file" >&5
-$as_echo "$as_me: creating cache $cache_file" >&6;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating cache $cache_file" >&5
+printf "%s\n" "$as_me: creating cache $cache_file" >&6;}
   >$cache_file
 fi
 
+# Test code for whether the C compiler supports C89 (global declarations)
+ac_c_conftest_c89_globals='
+/* Does the compiler advertise C89 conformance?
+   Do not test the value of __STDC__, because some compilers set it to 0
+   while being otherwise adequately conformant. */
+#if !defined __STDC__
+# error "Compiler does not advertise C89 conformance"
+#endif
+
+#include <stddef.h>
+#include <stdarg.h>
+struct stat;
+/* Most of the following tests are stolen from RCS 5.7 src/conf.sh.  */
+struct buf { int x; };
+struct buf * (*rcsopen) (struct buf *, struct stat *, int);
+static char *e (char **p, int i)
+{
+  return p[i];
+}
+static char *f (char * (*g) (char **, int), char **p, ...)
+{
+  char *s;
+  va_list v;
+  va_start (v,p);
+  s = g (p, va_arg (v,int));
+  va_end (v);
+  return s;
+}
+
+/* C89 style stringification. */
+#define noexpand_stringify(a) #a
+const char *stringified = noexpand_stringify(arbitrary+token=sequence);
+
+/* C89 style token pasting.  Exercises some of the corner cases that
+   e.g. old MSVC gets wrong, but not very hard. */
+#define noexpand_concat(a,b) a##b
+#define expand_concat(a,b) noexpand_concat(a,b)
+extern int vA;
+extern int vbee;
+#define aye A
+#define bee B
+int *pvA = &expand_concat(v,aye);
+int *pvbee = &noexpand_concat(v,bee);
+
+/* OSF 4.0 Compaq cc is some sort of almost-ANSI by default.  It has
+   function prototypes and stuff, but not \xHH hex character constants.
+   These do not provoke an error unfortunately, instead are silently treated
+   as an "x".  The following induces an error, until -std is added to get
+   proper ANSI mode.  Curiously \x00 != x always comes out true, for an
+   array size at least.  It is necessary to write \x00 == 0 to get something
+   that is true only with -std.  */
+int osf4_cc_array ['\''\x00'\'' == 0 ? 1 : -1];
+
+/* IBM C 6 for AIX is almost-ANSI by default, but it replaces macro parameters
+   inside strings and character constants.  */
+#define FOO(x) '\''x'\''
+int xlc6_cc_array[FOO(a) == '\''x'\'' ? 1 : -1];
+
+int test (int i, double x);
+struct s1 {int (*f) (int a);};
+struct s2 {int (*f) (double a);};
+int pairnames (int, char **, int *(*)(struct buf *, struct stat *, int),
+               int, int);'
+
+# Test code for whether the C compiler supports C89 (body of main).
+ac_c_conftest_c89_main='
+ok |= (argc == 0 || f (e, argv, 0) != argv[0] || f (e, argv, 1) != argv[1]);
+'
+
+# Test code for whether the C compiler supports C99 (global declarations)
+ac_c_conftest_c99_globals='
+/* Does the compiler advertise C99 conformance? */
+#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 199901L
+# error "Compiler does not advertise C99 conformance"
+#endif
+
+// See if C++-style comments work.
+
+#include <stdbool.h>
+extern int puts (const char *);
+extern int printf (const char *, ...);
+extern int dprintf (int, const char *, ...);
+extern void *malloc (size_t);
+extern void free (void *);
+
+// Check varargs macros.  These examples are taken from C99 6.10.3.5.
+// dprintf is used instead of fprintf to avoid needing to declare
+// FILE and stderr.
+#define debug(...) dprintf (2, __VA_ARGS__)
+#define showlist(...) puts (#__VA_ARGS__)
+#define report(test,...) ((test) ? puts (#test) : printf (__VA_ARGS__))
+static void
+test_varargs_macros (void)
+{
+  int x = 1234;
+  int y = 5678;
+  debug ("Flag");
+  debug ("X = %d\n", x);
+  showlist (The first, second, and third items.);
+  report (x>y, "x is %d but y is %d", x, y);
+}
+
+// Check long long types.
+#define BIG64 18446744073709551615ull
+#define BIG32 4294967295ul
+#define BIG_OK (BIG64 / BIG32 == 4294967297ull && BIG64 % BIG32 == 0)
+#if !BIG_OK
+  #error "your preprocessor is broken"
+#endif
+#if BIG_OK
+#else
+  #error "your preprocessor is broken"
+#endif
+static long long int bignum = -9223372036854775807LL;
+static unsigned long long int ubignum = BIG64;
+
+struct incomplete_array
+{
+  int datasize;
+  double data[];
+};
+
+struct named_init {
+  int number;
+  const wchar_t *name;
+  double average;
+};
+
+typedef const char *ccp;
+
+static inline int
+test_restrict (ccp restrict text)
+{
+  // Iterate through items via the restricted pointer.
+  // Also check for declarations in for loops.
+  for (unsigned int i = 0; *(text+i) != '\''\0'\''; ++i)
+    continue;
+  return 0;
+}
+
+// Check varargs and va_copy.
+static bool
+test_varargs (const char *format, ...)
+{
+  va_list args;
+  va_start (args, format);
+  va_list args_copy;
+  va_copy (args_copy, args);
+
+  const char *str = "";
+  int number = 0;
+  float fnumber = 0;
+
+  while (*format)
+    {
+      switch (*format++)
+	{
+	case '\''s'\'': // string
+	  str = va_arg (args_copy, const char *);
+	  break;
+	case '\''d'\'': // int
+	  number = va_arg (args_copy, int);
+	  break;
+	case '\''f'\'': // float
+	  fnumber = va_arg (args_copy, double);
+	  break;
+	default:
+	  break;
+	}
+    }
+  va_end (args_copy);
+  va_end (args);
+
+  return *str && number && fnumber;
+}
+'
+
+# Test code for whether the C compiler supports C99 (body of main).
+ac_c_conftest_c99_main='
+  // Check bool.
+  _Bool success = false;
+  success |= (argc != 0);
+
+  // Check restrict.
+  if (test_restrict ("String literal") == 0)
+    success = true;
+  char *restrict newvar = "Another string";
+
+  // Check varargs.
+  success &= test_varargs ("s, d'\'' f .", "string", 65, 34.234);
+  test_varargs_macros ();
+
+  // Check flexible array members.
+  struct incomplete_array *ia =
+    malloc (sizeof (struct incomplete_array) + (sizeof (double) * 10));
+  ia->datasize = 10;
+  for (int i = 0; i < ia->datasize; ++i)
+    ia->data[i] = i * 1.234;
+  // Work around memory leak warnings.
+  free (ia);
+
+  // Check named initializers.
+  struct named_init ni = {
+    .number = 34,
+    .name = L"Test wide string",
+    .average = 543.34343,
+  };
+
+  ni.number = 58;
+
+  int dynamic_array[ni.number];
+  dynamic_array[0] = argv[0][0];
+  dynamic_array[ni.number - 1] = 543;
+
+  // work around unused variable warnings
+  ok |= (!success || bignum == 0LL || ubignum == 0uLL || newvar[0] == '\''x'\''
+	 || dynamic_array[ni.number - 1] != 543);
+'
+
+# Test code for whether the C compiler supports C11 (global declarations)
+ac_c_conftest_c11_globals='
+/* Does the compiler advertise C11 conformance? */
+#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112L
+# error "Compiler does not advertise C11 conformance"
+#endif
+
+// Check _Alignas.
+char _Alignas (double) aligned_as_double;
+char _Alignas (0) no_special_alignment;
+extern char aligned_as_int;
+char _Alignas (0) _Alignas (int) aligned_as_int;
+
+// Check _Alignof.
+enum
+{
+  int_alignment = _Alignof (int),
+  int_array_alignment = _Alignof (int[100]),
+  char_alignment = _Alignof (char)
+};
+_Static_assert (0 < -_Alignof (int), "_Alignof is signed");
+
+// Check _Noreturn.
+int _Noreturn does_not_return (void) { for (;;) continue; }
+
+// Check _Static_assert.
+struct test_static_assert
+{
+  int x;
+  _Static_assert (sizeof (int) <= sizeof (long int),
+                  "_Static_assert does not work in struct");
+  long int y;
+};
+
+// Check UTF-8 literals.
+#define u8 syntax error!
+char const utf8_literal[] = u8"happens to be ASCII" "another string";
+
+// Check duplicate typedefs.
+typedef long *long_ptr;
+typedef long int *long_ptr;
+typedef long_ptr long_ptr;
+
+// Anonymous structures and unions -- taken from C11 6.7.2.1 Example 1.
+struct anonymous
+{
+  union {
+    struct { int i; int j; };
+    struct { int k; long int l; } w;
+  };
+  int m;
+} v1;
+'
+
+# Test code for whether the C compiler supports C11 (body of main).
+ac_c_conftest_c11_main='
+  _Static_assert ((offsetof (struct anonymous, i)
+		   == offsetof (struct anonymous, w.k)),
+		  "Anonymous union alignment botch");
+  v1.i = 2;
+  v1.w.k = 5;
+  ok |= v1.i != 5;
+'
+
+# Test code for whether the C compiler supports C11 (complete).
+ac_c_conftest_c11_program="${ac_c_conftest_c89_globals}
+${ac_c_conftest_c99_globals}
+${ac_c_conftest_c11_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  ${ac_c_conftest_c99_main}
+  ${ac_c_conftest_c11_main}
+  return ok;
+}
+"
+
+# Test code for whether the C compiler supports C99 (complete).
+ac_c_conftest_c99_program="${ac_c_conftest_c89_globals}
+${ac_c_conftest_c99_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  ${ac_c_conftest_c99_main}
+  return ok;
+}
+"
+
+# Test code for whether the C compiler supports C89 (complete).
+ac_c_conftest_c89_program="${ac_c_conftest_c89_globals}
+
+int
+main (int argc, char **argv)
+{
+  int ok = 0;
+  ${ac_c_conftest_c89_main}
+  return ok;
+}
+"
+
+as_fn_append ac_header_c_list " stdio.h stdio_h HAVE_STDIO_H"
+as_fn_append ac_header_c_list " stdlib.h stdlib_h HAVE_STDLIB_H"
+as_fn_append ac_header_c_list " string.h string_h HAVE_STRING_H"
+as_fn_append ac_header_c_list " inttypes.h inttypes_h HAVE_INTTYPES_H"
+as_fn_append ac_header_c_list " stdint.h stdint_h HAVE_STDINT_H"
+as_fn_append ac_header_c_list " strings.h strings_h HAVE_STRINGS_H"
+as_fn_append ac_header_c_list " sys/stat.h sys_stat_h HAVE_SYS_STAT_H"
+as_fn_append ac_header_c_list " sys/types.h sys_types_h HAVE_SYS_TYPES_H"
+as_fn_append ac_header_c_list " unistd.h unistd_h HAVE_UNISTD_H"
+
+# Auxiliary files required by this configure script.
+ac_aux_files="ltmain.sh config.guess config.sub compile missing install-sh"
+
+# Locations in which to look for auxiliary files.
+ac_aux_dir_candidates="${srcdir}${PATH_SEPARATOR}${srcdir}/..${PATH_SEPARATOR}${srcdir}/../.."
+
+# Search for a directory containing all of the required auxiliary files,
+# $ac_aux_files, from the $PATH-style list $ac_aux_dir_candidates.
+# If we don't find one directory that contains all the files we need,
+# we report the set of missing files from the *first* directory in
+# $ac_aux_dir_candidates and give up.
+ac_missing_aux_files=""
+ac_first_candidate=:
+printf "%s\n" "$as_me:${as_lineno-$LINENO}: looking for aux files: $ac_aux_files" >&5
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+as_found=false
+for as_dir in $ac_aux_dir_candidates
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+  as_found=:
+
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}:  trying $as_dir" >&5
+  ac_aux_dir_found=yes
+  ac_install_sh=
+  for ac_aux in $ac_aux_files
+  do
+    # As a special case, if "install-sh" is required, that requirement
+    # can be satisfied by any of "install-sh", "install.sh", or "shtool",
+    # and $ac_install_sh is set appropriately for whichever one is found.
+    if test x"$ac_aux" = x"install-sh"
+    then
+      if test -f "${as_dir}install-sh"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}install-sh found" >&5
+        ac_install_sh="${as_dir}install-sh -c"
+      elif test -f "${as_dir}install.sh"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}install.sh found" >&5
+        ac_install_sh="${as_dir}install.sh -c"
+      elif test -f "${as_dir}shtool"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}shtool found" >&5
+        ac_install_sh="${as_dir}shtool install -c"
+      else
+        ac_aux_dir_found=no
+        if $ac_first_candidate; then
+          ac_missing_aux_files="${ac_missing_aux_files} install-sh"
+        else
+          break
+        fi
+      fi
+    else
+      if test -f "${as_dir}${ac_aux}"; then
+        printf "%s\n" "$as_me:${as_lineno-$LINENO}:   ${as_dir}${ac_aux} found" >&5
+      else
+        ac_aux_dir_found=no
+        if $ac_first_candidate; then
+          ac_missing_aux_files="${ac_missing_aux_files} ${ac_aux}"
+        else
+          break
+        fi
+      fi
+    fi
+  done
+  if test "$ac_aux_dir_found" = yes; then
+    ac_aux_dir="$as_dir"
+    break
+  fi
+  ac_first_candidate=false
+
+  as_found=false
+done
+IFS=$as_save_IFS
+if $as_found
+then :
+
+else case e in #(
+  e) as_fn_error $? "cannot find required auxiliary files:$ac_missing_aux_files" "$LINENO" 5 ;;
+esac
+fi
+
+
+# These three variables are undocumented and unsupported,
+# and are intended to be withdrawn in a future Autoconf release.
+# They can cause serious problems if a builder's source tree is in a directory
+# whose full name contains unusual characters.
+if test -f "${ac_aux_dir}config.guess"; then
+  ac_config_guess="$SHELL ${ac_aux_dir}config.guess"
+fi
+if test -f "${ac_aux_dir}config.sub"; then
+  ac_config_sub="$SHELL ${ac_aux_dir}config.sub"
+fi
+if test -f "$ac_aux_dir/configure"; then
+  ac_configure="$SHELL ${ac_aux_dir}configure"
+fi
+
 # Check that the precious variables saved in the cache have kept the same
 # value.
 ac_cache_corrupted=false
@@ -2244,12 +2660,12 @@
   eval ac_new_val=\$ac_env_${ac_var}_value
   case $ac_old_set,$ac_new_set in
     set,)
-      { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&5
-$as_echo "$as_me: error: \`$ac_var' was set to \`$ac_old_val' in the previous run" >&2;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: '$ac_var' was set to '$ac_old_val' in the previous run" >&5
+printf "%s\n" "$as_me: error: '$ac_var' was set to '$ac_old_val' in the previous run" >&2;}
       ac_cache_corrupted=: ;;
     ,set)
-      { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' was not set in the previous run" >&5
-$as_echo "$as_me: error: \`$ac_var' was not set in the previous run" >&2;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: '$ac_var' was not set in the previous run" >&5
+printf "%s\n" "$as_me: error: '$ac_var' was not set in the previous run" >&2;}
       ac_cache_corrupted=: ;;
     ,);;
     *)
@@ -2258,24 +2674,24 @@
 	ac_old_val_w=`echo x $ac_old_val`
 	ac_new_val_w=`echo x $ac_new_val`
 	if test "$ac_old_val_w" != "$ac_new_val_w"; then
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: error: \`$ac_var' has changed since the previous run:" >&5
-$as_echo "$as_me: error: \`$ac_var' has changed since the previous run:" >&2;}
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: '$ac_var' has changed since the previous run:" >&5
+printf "%s\n" "$as_me: error: '$ac_var' has changed since the previous run:" >&2;}
 	  ac_cache_corrupted=:
 	else
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&5
-$as_echo "$as_me: warning: ignoring whitespace changes in \`$ac_var' since the previous run:" >&2;}
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: warning: ignoring whitespace changes in '$ac_var' since the previous run:" >&5
+printf "%s\n" "$as_me: warning: ignoring whitespace changes in '$ac_var' since the previous run:" >&2;}
 	  eval $ac_var=\$ac_old_val
 	fi
-	{ $as_echo "$as_me:${as_lineno-$LINENO}:   former value:  \`$ac_old_val'" >&5
-$as_echo "$as_me:   former value:  \`$ac_old_val'" >&2;}
-	{ $as_echo "$as_me:${as_lineno-$LINENO}:   current value: \`$ac_new_val'" >&5
-$as_echo "$as_me:   current value: \`$ac_new_val'" >&2;}
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}:   former value:  '$ac_old_val'" >&5
+printf "%s\n" "$as_me:   former value:  '$ac_old_val'" >&2;}
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}:   current value: '$ac_new_val'" >&5
+printf "%s\n" "$as_me:   current value: '$ac_new_val'" >&2;}
       fi;;
   esac
   # Pass precious variables to config.status.
   if test "$ac_new_set" = set; then
     case $ac_new_val in
-    *\'*) ac_arg=$ac_var=`$as_echo "$ac_new_val" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_arg=$ac_var=`printf "%s\n" "$ac_new_val" | sed "s/'/'\\\\\\\\''/g"` ;;
     *) ac_arg=$ac_var=$ac_new_val ;;
     esac
     case " $ac_configure_args " in
@@ -2285,11 +2701,12 @@
   fi
 done
 if $ac_cache_corrupted; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
-  { $as_echo "$as_me:${as_lineno-$LINENO}: error: changes in the environment can compromise the build" >&5
-$as_echo "$as_me: error: changes in the environment can compromise the build" >&2;}
-  as_fn_error $? "run \`make distclean' and/or \`rm $cache_file' and start over" "$LINENO" 5
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: changes in the environment can compromise the build" >&5
+printf "%s\n" "$as_me: error: changes in the environment can compromise the build" >&2;}
+  as_fn_error $? "run '${MAKE-make} distclean' and/or 'rm $cache_file'
+	    and start over" "$LINENO" 5
 fi
 ## -------------------- ##
 ## Main body of script. ##
@@ -2312,36 +2729,9 @@
 # 1.13 is required for parallel tests
 am__api_version='1.16'
 
-ac_aux_dir=
-for ac_dir in "$srcdir" "$srcdir/.." "$srcdir/../.."; do
-  if test -f "$ac_dir/install-sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install-sh -c"
-    break
-  elif test -f "$ac_dir/install.sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install.sh -c"
-    break
-  elif test -f "$ac_dir/shtool"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/shtool install -c"
-    break
-  fi
-done
-if test -z "$ac_aux_dir"; then
-  as_fn_error $? "cannot find install-sh, install.sh, or shtool in \"$srcdir\" \"$srcdir/..\" \"$srcdir/../..\"" "$LINENO" 5
-fi
-
-# These three variables are undocumented and unsupported,
-# and are intended to be withdrawn in a future Autoconf release.
-# They can cause serious problems if a builder's source tree is in a directory
-# whose full name contains unusual characters.
-ac_config_guess="$SHELL $ac_aux_dir/config.guess"  # Please don't use this var.
-ac_config_sub="$SHELL $ac_aux_dir/config.sub"  # Please don't use this var.
-ac_configure="$SHELL $ac_aux_dir/configure"  # Please don't use this var.
 
 
-# Find a good install program.  We prefer a C program (faster),
+  # Find a good install program.  We prefer a C program (faster),
 # so one script is as good as another.  But avoid the broken or
 # incompatible versions:
 # SysV /etc/install, /usr/sbin/install
@@ -2355,20 +2745,25 @@
 # OS/2's system install, which has a completely different semantic
 # ./install, which can be erroneously created by make from ./install.sh.
 # Reject install programs that cannot install multiple files.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a BSD-compatible install" >&5
-$as_echo_n "checking for a BSD-compatible install... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a BSD-compatible install" >&5
+printf %s "checking for a BSD-compatible install... " >&6; }
 if test -z "$INSTALL"; then
-if ${ac_cv_path_install+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+if test ${ac_cv_path_install+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    # Account for people who put trailing slashes in PATH elements.
-case $as_dir/ in #((
-  ./ | .// | /[cC]/* | \
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    # Account for fact that we put trailing slashes in our PATH walk.
+case $as_dir in #((
+  ./ | /[cC]/* | \
   /etc/* | /usr/sbin/* | /usr/etc/* | /sbin/* | /usr/afsws/bin/* | \
   ?:[\\/]os2[\\/]install[\\/]* | ?:[\\/]OS2[\\/]INSTALL[\\/]* | \
   /usr/ucb/* ) ;;
@@ -2378,13 +2773,13 @@
     # by default.
     for ac_prog in ginstall scoinst install; do
       for ac_exec_ext in '' $ac_executable_extensions; do
-	if as_fn_executable_p "$as_dir/$ac_prog$ac_exec_ext"; then
+	if as_fn_executable_p "$as_dir$ac_prog$ac_exec_ext"; then
 	  if test $ac_prog = install &&
-	    grep dspmsg "$as_dir/$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
+	    grep dspmsg "$as_dir$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
 	    # AIX install.  It has an incompatible calling convention.
 	    :
 	  elif test $ac_prog = install &&
-	    grep pwplus "$as_dir/$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
+	    grep pwplus "$as_dir$ac_prog$ac_exec_ext" >/dev/null 2>&1; then
 	    # program-specific install script used by HP pwplus--don't use.
 	    :
 	  else
@@ -2392,12 +2787,12 @@
 	    echo one > conftest.one
 	    echo two > conftest.two
 	    mkdir conftest.dir
-	    if "$as_dir/$ac_prog$ac_exec_ext" -c conftest.one conftest.two "`pwd`/conftest.dir" &&
+	    if "$as_dir$ac_prog$ac_exec_ext" -c conftest.one conftest.two "`pwd`/conftest.dir/" &&
 	      test -s conftest.one && test -s conftest.two &&
 	      test -s conftest.dir/conftest.one &&
 	      test -s conftest.dir/conftest.two
 	    then
-	      ac_cv_path_install="$as_dir/$ac_prog$ac_exec_ext -c"
+	      ac_cv_path_install="$as_dir$ac_prog$ac_exec_ext -c"
 	      break 3
 	    fi
 	  fi
@@ -2411,9 +2806,10 @@
 IFS=$as_save_IFS
 
 rm -rf conftest.one conftest.two conftest.dir
-
+ ;;
+esac
 fi
-  if test "${ac_cv_path_install+set}" = set; then
+  if test ${ac_cv_path_install+y}; then
     INSTALL=$ac_cv_path_install
   else
     # As a last resort, use the slow shell script.  Don't cache a
@@ -2423,8 +2819,8 @@
     INSTALL=$ac_install_sh
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $INSTALL" >&5
-$as_echo "$INSTALL" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $INSTALL" >&5
+printf "%s\n" "$INSTALL" >&6; }
 
 # Use test -z because SunOS4 sh mishandles braces in ${var-val}.
 # It thinks the first close brace ends the variable substitution.
@@ -2434,8 +2830,8 @@
 
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether build environment is sane" >&5
-$as_echo_n "checking whether build environment is sane... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether build environment is sane" >&5
+printf %s "checking whether build environment is sane... " >&6; }
 # Reject unsafe characters in $srcdir or the absolute working directory
 # name.  Accept space and tab only in the latter.
 am_lf='
@@ -2489,8 +2885,8 @@
    as_fn_error $? "newly created file is older than distributed files!
 Check your system clock" "$LINENO" 5
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 # If we didn't sleep, we still need to ensure time stamps of config.status and
 # generated files are strictly newer.
 am_sleep_pid=
@@ -2507,28 +2903,25 @@
 test "$program_suffix" != NONE &&
   program_transform_name="s&\$&$program_suffix&;$program_transform_name"
 # Double any \ or $.
-# By default was `s,x,x', remove it if useless.
+# By default was 's,x,x', remove it if useless.
 ac_script='s/[\\$]/&&/g;s/;s,x,x,$//'
-program_transform_name=`$as_echo "$program_transform_name" | sed "$ac_script"`
+program_transform_name=`printf "%s\n" "$program_transform_name" | sed "$ac_script"`
+
 
 # Expand $ac_aux_dir to an absolute path.
 am_aux_dir=`cd "$ac_aux_dir" && pwd`
 
-if test x"${MISSING+set}" != xset; then
-  case $am_aux_dir in
-  *\ * | *\	*)
-    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
-  *)
-    MISSING="\${SHELL} $am_aux_dir/missing" ;;
-  esac
+
+  if test x"${MISSING+set}" != xset; then
+  MISSING="\${SHELL} '$am_aux_dir/missing'"
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
   am_missing_run="$MISSING "
 else
   am_missing_run=
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: 'missing' script is too old or missing" >&5
-$as_echo "$as_me: WARNING: 'missing' script is too old or missing" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: 'missing' script is too old or missing" >&5
+printf "%s\n" "$as_me: WARNING: 'missing' script is too old or missing" >&2;}
 fi
 
 if test x"${install_sh+set}" != xset; then
@@ -2548,38 +2941,44 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}strip", so it can be a program name with args.
 set dummy ${ac_tool_prefix}strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$STRIP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$STRIP"; then
   ac_cv_prog_STRIP="$STRIP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_STRIP="${ac_tool_prefix}strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 STRIP=$ac_cv_prog_STRIP
 if test -n "$STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
-$as_echo "$STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
+printf "%s\n" "$STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -2588,38 +2987,44 @@
   ac_ct_STRIP=$STRIP
   # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_STRIP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_STRIP"; then
   ac_cv_prog_ac_ct_STRIP="$ac_ct_STRIP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_STRIP="strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_STRIP=$ac_cv_prog_ac_ct_STRIP
 if test -n "$ac_ct_STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
-$as_echo "$ac_ct_STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
+printf "%s\n" "$ac_ct_STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_STRIP" = x; then
@@ -2627,8 +3032,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     STRIP=$ac_ct_STRIP
@@ -2640,98 +3045,110 @@
 fi
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a thread-safe mkdir -p" >&5
-$as_echo_n "checking for a thread-safe mkdir -p... " >&6; }
+
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a race-free mkdir -p" >&5
+printf %s "checking for a race-free mkdir -p... " >&6; }
 if test -z "$MKDIR_P"; then
-  if ${ac_cv_path_mkdir+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+  if test ${ac_cv_path_mkdir+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH$PATH_SEPARATOR/opt/sfw/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_prog in mkdir gmkdir; do
 	 for ac_exec_ext in '' $ac_executable_extensions; do
-	   as_fn_executable_p "$as_dir/$ac_prog$ac_exec_ext" || continue
-	   case `"$as_dir/$ac_prog$ac_exec_ext" --version 2>&1` in #(
-	     'mkdir (GNU coreutils) '* | \
-	     'mkdir (coreutils) '* | \
+	   as_fn_executable_p "$as_dir$ac_prog$ac_exec_ext" || continue
+	   case `"$as_dir$ac_prog$ac_exec_ext" --version 2>&1` in #(
+	     'mkdir ('*'coreutils) '* | \
+	     *'BusyBox '* | \
 	     'mkdir (fileutils) '4.1*)
-	       ac_cv_path_mkdir=$as_dir/$ac_prog$ac_exec_ext
+	       ac_cv_path_mkdir=$as_dir$ac_prog$ac_exec_ext
 	       break 3;;
 	   esac
 	 done
        done
   done
 IFS=$as_save_IFS
-
+ ;;
+esac
 fi
 
   test -d ./--version && rmdir ./--version
-  if test "${ac_cv_path_mkdir+set}" = set; then
+  if test ${ac_cv_path_mkdir+y}; then
     MKDIR_P="$ac_cv_path_mkdir -p"
   else
-    # As a last resort, use the slow shell script.  Don't cache a
-    # value for MKDIR_P within a source directory, because that will
-    # break other packages using the cache if that directory is
-    # removed, or if the value is a relative name.
-    MKDIR_P="$ac_install_sh -d"
+    # As a last resort, use plain mkdir -p,
+    # in the hope it doesn't have the bugs of ancient mkdir.
+    MKDIR_P='mkdir -p'
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $MKDIR_P" >&5
-$as_echo "$MKDIR_P" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MKDIR_P" >&5
+printf "%s\n" "$MKDIR_P" >&6; }
 
 for ac_prog in gawk mawk nawk awk
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AWK+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$AWK"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AWK+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$AWK"; then
   ac_cv_prog_AWK="$AWK" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AWK="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 AWK=$ac_cv_prog_AWK
 if test -n "$AWK"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
-$as_echo "$AWK" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
+printf "%s\n" "$AWK" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
   test -n "$AWK" && break
 done
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
-$as_echo_n "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
+printf %s "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
 set x ${MAKE-make}
-ac_make=`$as_echo "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
-if eval \${ac_cv_prog_make_${ac_make}_set+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat >conftest.make <<\_ACEOF
+ac_make=`printf "%s\n" "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
+if eval test \${ac_cv_prog_make_${ac_make}_set+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat >conftest.make <<\_ACEOF
 SHELL = /bin/sh
 all:
 	@echo '@@@%%%=$(MAKE)=@@@%%%'
@@ -2743,15 +3160,16 @@
   *)
     eval ac_cv_prog_make_${ac_make}_set=no;;
 esac
-rm -f conftest.make
+rm -f conftest.make ;;
+esac
 fi
 if eval test \$ac_cv_prog_make_${ac_make}_set = yes; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
   SET_MAKE=
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
   SET_MAKE="MAKE=${MAKE-make}"
 fi
 
@@ -2765,7 +3183,8 @@
 rmdir .tst 2>/dev/null
 
 # Check whether --enable-silent-rules was given.
-if test "${enable_silent_rules+set}" = set; then :
+if test ${enable_silent_rules+y}
+then :
   enableval=$enable_silent_rules;
 fi
 
@@ -2775,12 +3194,13 @@
     *) AM_DEFAULT_VERBOSITY=1;;
 esac
 am_make=${MAKE-make}
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $am_make supports nested variables" >&5
-$as_echo_n "checking whether $am_make supports nested variables... " >&6; }
-if ${am_cv_make_support_nested_variables+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if $as_echo 'TRUE=$(BAR$(V))
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $am_make supports nested variables" >&5
+printf %s "checking whether $am_make supports nested variables... " >&6; }
+if test ${am_cv_make_support_nested_variables+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if printf "%s\n" 'TRUE=$(BAR$(V))
 BAR0=false
 BAR1=true
 V=1
@@ -2790,10 +3210,11 @@
   am_cv_make_support_nested_variables=yes
 else
   am_cv_make_support_nested_variables=no
+fi ;;
+esac
 fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_make_support_nested_variables" >&5
-$as_echo "$am_cv_make_support_nested_variables" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_make_support_nested_variables" >&5
+printf "%s\n" "$am_cv_make_support_nested_variables" >&6; }
 if test $am_cv_make_support_nested_variables = yes; then
     AM_V='$(V)'
   AM_DEFAULT_V='$(AM_DEFAULT_VERBOSITY)'
@@ -2825,17 +3246,13 @@
 
 # Define the identity of the package.
  PACKAGE='libpng'
- VERSION='1.6.38.git'
+ VERSION='1.6.43.git'
 
 
-cat >>confdefs.h <<_ACEOF
-#define PACKAGE "$PACKAGE"
-_ACEOF
+printf "%s\n" "#define PACKAGE \"$PACKAGE\"" >>confdefs.h
 
 
-cat >>confdefs.h <<_ACEOF
-#define VERSION "$VERSION"
-_ACEOF
+printf "%s\n" "#define VERSION \"$VERSION\"" >>confdefs.h
 
 # Some tools Automake needs.
 
@@ -2875,6 +3292,20 @@
 
 
 
+# Variables for tags utilities; see am/tags.am
+if test -z "$CTAGS"; then
+  CTAGS=ctags
+fi
+
+if test -z "$ETAGS"; then
+  ETAGS=etags
+fi
+
+if test -z "$CSCOPE"; then
+  CSCOPE=cscope
+fi
+
+
 
 # POSIX will say in a future version that running "rm -f" with no argument
 # is OK; and we want to be able to make that assumption in our Makefile
@@ -2922,17 +3353,19 @@
 # configure. This is necessary because libpng distributions cannot rely on the
 # time stamps of the autotools generated files being correct
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to enable maintainer-specific portions of Makefiles" >&5
-$as_echo_n "checking whether to enable maintainer-specific portions of Makefiles... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to enable maintainer-specific portions of Makefiles" >&5
+printf %s "checking whether to enable maintainer-specific portions of Makefiles... " >&6; }
     # Check whether --enable-maintainer-mode was given.
-if test "${enable_maintainer_mode+set}" = set; then :
+if test ${enable_maintainer_mode+y}
+then :
   enableval=$enable_maintainer_mode; USE_MAINTAINER_MODE=$enableval
-else
-  USE_MAINTAINER_MODE=no
+else case e in #(
+  e) USE_MAINTAINER_MODE=no ;;
+esac
 fi
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $USE_MAINTAINER_MODE" >&5
-$as_echo "$USE_MAINTAINER_MODE" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $USE_MAINTAINER_MODE" >&5
+printf "%s\n" "$USE_MAINTAINER_MODE" >&6; }
    if test $USE_MAINTAINER_MODE = yes; then
   MAINTAINER_MODE_TRUE=
   MAINTAINER_MODE_FALSE='#'
@@ -2946,10 +3379,10 @@
 
 
 
-PNGLIB_VERSION=1.6.38.git
+PNGLIB_VERSION=1.6.43.git
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=38
+PNGLIB_RELEASE=43
 
 
 
@@ -2963,6 +3396,15 @@
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
+
+
+
+
+
+
+
+
+
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
@@ -2971,38 +3413,44 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}gcc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}gcc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="${ac_tool_prefix}gcc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3011,38 +3459,44 @@
   ac_ct_CC=$CC
   # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_CC"; then
   ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_CC="gcc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_CC=$ac_cv_prog_ac_ct_CC
 if test -n "$ac_ct_CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
-$as_echo "$ac_ct_CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_CC" = x; then
@@ -3050,8 +3504,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     CC=$ac_ct_CC
@@ -3064,38 +3518,44 @@
           if test -n "$ac_tool_prefix"; then
     # Extract the first word of "${ac_tool_prefix}cc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}cc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="${ac_tool_prefix}cc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3104,12 +3564,13 @@
 if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
   ac_prog_rejected=no
@@ -3117,15 +3578,19 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    if test "$as_dir/$ac_word$ac_exec_ext" = "/usr/ucb/cc"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    if test "$as_dir$ac_word$ac_exec_ext" = "/usr/ucb/cc"; then
        ac_prog_rejected=yes
        continue
      fi
     ac_cv_prog_CC="cc"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
@@ -3141,18 +3606,19 @@
     # However, it has the same basename, so the bogon will be chosen
     # first if we set CC to just the basename; use the full file name.
     shift
-    ac_cv_prog_CC="$as_dir/$ac_word${1+' '}$@"
+    ac_cv_prog_CC="$as_dir$ac_word${1+' '}$@"
   fi
 fi
-fi
+fi ;;
+esac
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3163,38 +3629,44 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$CC"; then
   ac_cv_prog_CC="$CC" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_CC="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 CC=$ac_cv_prog_CC
 if test -n "$CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
-$as_echo "$CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3207,38 +3679,44 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_CC+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_CC"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_CC"; then
   ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_CC="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_CC=$ac_cv_prog_ac_ct_CC
 if test -n "$ac_ct_CC"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
-$as_echo "$ac_ct_CC" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -3250,8 +3728,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     CC=$ac_ct_CC
@@ -3259,25 +3737,131 @@
 fi
 
 fi
+if test -z "$CC"; then
+  if test -n "$ac_tool_prefix"; then
+  # Extract the first word of "${ac_tool_prefix}clang", so it can be a program name with args.
+set dummy ${ac_tool_prefix}clang; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$CC"; then
+  ac_cv_prog_CC="$CC" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_CC="${ac_tool_prefix}clang"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi ;;
+esac
+fi
+CC=$ac_cv_prog_CC
+if test -n "$CC"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CC" >&5
+printf "%s\n" "$CC" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
 
 
-test -z "$CC" && { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+fi
+if test -z "$ac_cv_prog_CC"; then
+  ac_ct_CC=$CC
+  # Extract the first word of "clang", so it can be a program name with args.
+set dummy clang; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_CC+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_CC"; then
+  ac_cv_prog_ac_ct_CC="$ac_ct_CC" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_ac_ct_CC="clang"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi ;;
+esac
+fi
+ac_ct_CC=$ac_cv_prog_ac_ct_CC
+if test -n "$ac_ct_CC"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_CC" >&5
+printf "%s\n" "$ac_ct_CC" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+  if test "x$ac_ct_CC" = x; then
+    CC=""
+  else
+    case $cross_compiling:$ac_tool_warned in
+yes:)
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+ac_tool_warned=yes ;;
+esac
+    CC=$ac_ct_CC
+  fi
+else
+  CC="$ac_cv_prog_CC"
+fi
+
+fi
+
+
+test -z "$CC" && { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "no acceptable C compiler found in \$PATH
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; }
 
 # Provide some information about the compiler.
-$as_echo "$as_me:${as_lineno-$LINENO}: checking for C compiler version" >&5
+printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C compiler version" >&5
 set X $ac_compile
 ac_compiler=$2
-for ac_option in --version -v -V -qversion; do
+for ac_option in --version -v -V -qversion -version; do
   { { ac_try="$ac_compiler $ac_option >&5"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compiler $ac_option >&5") 2>conftest.err
   ac_status=$?
   if test -s conftest.err; then
@@ -3287,7 +3871,7 @@
     cat conftest.er1 >&5
   fi
   rm -f conftest.er1 conftest.err
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 done
 
@@ -3295,7 +3879,7 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3307,9 +3891,9 @@
 # Try to create an executable without -o first, disregard a.out.
 # It will help us diagnose broken compilers, and finding out an intuition
 # of exeext.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the C compiler works" >&5
-$as_echo_n "checking whether the C compiler works... " >&6; }
-ac_link_default=`$as_echo "$ac_link" | sed 's/ -o *conftest[^ ]*//'`
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the C compiler works" >&5
+printf %s "checking whether the C compiler works... " >&6; }
+ac_link_default=`printf "%s\n" "$ac_link" | sed 's/ -o *conftest[^ ]*//'`
 
 # The possible output files:
 ac_files="a.out conftest.exe conftest a.exe a_out.exe b.out conftest.*"
@@ -3330,13 +3914,14 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link_default") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
-  # Autoconf-2.13 could set the ac_cv_exeext variable to `no'.
-# So ignore a value of `no', otherwise this would lead to `EXEEXT = no'
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
+  # Autoconf-2.13 could set the ac_cv_exeext variable to 'no'.
+# So ignore a value of 'no', otherwise this would lead to 'EXEEXT = no'
 # in a Makefile.  We should not override ac_cv_exeext if it was cached,
 # so that the user can short-circuit this test for compilers unknown to
 # Autoconf.
@@ -3351,12 +3936,12 @@
 	# certainly right.
 	break;;
     *.* )
-	if test "${ac_cv_exeext+set}" = set && test "$ac_cv_exeext" != no;
+	if test ${ac_cv_exeext+y} && test "$ac_cv_exeext" != no;
 	then :; else
 	   ac_cv_exeext=`expr "$ac_file" : '[^.]*\(\..*\)'`
 	fi
 	# We set ac_cv_exeext here because the later test for it is not
-	# safe: cross compilers may not add the suffix if given an `-o'
+	# safe: cross compilers may not add the suffix if given an '-o'
 	# argument, so we may need to know it at that point already.
 	# Even if this section looks crufty: it has the advantage of
 	# actually working.
@@ -3367,48 +3952,52 @@
 done
 test "$ac_cv_exeext" = no && ac_cv_exeext=
 
-else
-  ac_file=''
+else case e in #(
+  e) ac_file='' ;;
+esac
 fi
-if test -z "$ac_file"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-$as_echo "$as_me: failed program was:" >&5
+if test -z "$ac_file"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error 77 "C compiler cannot create executables
-See \`config.log' for more details" "$LINENO" 5; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+See 'config.log' for more details" "$LINENO" 5; }
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; } ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for C compiler default output file name" >&5
-$as_echo_n "checking for C compiler default output file name... " >&6; }
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_file" >&5
-$as_echo "$ac_file" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C compiler default output file name" >&5
+printf %s "checking for C compiler default output file name... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_file" >&5
+printf "%s\n" "$ac_file" >&6; }
 ac_exeext=$ac_cv_exeext
 
 rm -f -r a.out a.out.dSYM a.exe conftest$ac_cv_exeext b.out
 ac_clean_files=$ac_clean_files_save
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for suffix of executables" >&5
-$as_echo_n "checking for suffix of executables... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for suffix of executables" >&5
+printf %s "checking for suffix of executables... " >&6; }
 if { { ac_try="$ac_link"
 case "(($ac_try" in
   *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
-  # If both `conftest.exe' and `conftest' are `present' (well, observable)
-# catch `conftest.exe'.  For instance with Cygwin, `ls conftest' will
-# work properly (i.e., refer to `conftest.exe'), while it won't with
-# `rm'.
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
+  # If both 'conftest.exe' and 'conftest' are 'present' (well, observable)
+# catch 'conftest.exe'.  For instance with Cygwin, 'ls conftest' will
+# work properly (i.e., refer to 'conftest.exe'), while it won't with
+# 'rm'.
 for ac_file in conftest.exe conftest conftest.*; do
   test -f "$ac_file" || continue
   case $ac_file in
@@ -3418,15 +4007,16 @@
     * ) break;;
   esac
 done
-else
-  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+else case e in #(
+  e) { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "cannot compute suffix of executables: cannot compile and link
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; } ;;
+esac
 fi
 rm -f conftest conftest$ac_cv_exeext
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_exeext" >&5
-$as_echo "$ac_cv_exeext" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_exeext" >&5
+printf "%s\n" "$ac_cv_exeext" >&6; }
 
 rm -f conftest.$ac_ext
 EXEEXT=$ac_cv_exeext
@@ -3435,9 +4025,11 @@
 /* end confdefs.h.  */
 #include <stdio.h>
 int
-main ()
+main (void)
 {
 FILE *f = fopen ("conftest.out", "w");
+ if (!f)
+  return 1;
  return ferror (f) || fclose (f) != 0;
 
   ;
@@ -3447,8 +4039,8 @@
 ac_clean_files="$ac_clean_files conftest.out"
 # Check that the compiler produces executables we can run.  If not, either
 # the compiler is broken, or we cross compile.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether we are cross compiling" >&5
-$as_echo_n "checking whether we are cross compiling... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether we are cross compiling" >&5
+printf %s "checking whether we are cross compiling... " >&6; }
 if test "$cross_compiling" != yes; then
   { { ac_try="$ac_link"
 case "(($ac_try" in
@@ -3456,10 +4048,10 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_link") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
   if { ac_try='./conftest$ac_cv_exeext'
   { { case "(($ac_try" in
@@ -3467,39 +4059,41 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_try") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; }; then
     cross_compiling=no
   else
     if test "$cross_compiling" = maybe; then
 	cross_compiling=yes
     else
-	{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
-as_fn_error $? "cannot run C compiled programs.
-If you meant to cross compile, use \`--host'.
-See \`config.log' for more details" "$LINENO" 5; }
+	{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
+as_fn_error 77 "cannot run C compiled programs.
+If you meant to cross compile, use '--host'.
+See 'config.log' for more details" "$LINENO" 5; }
     fi
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $cross_compiling" >&5
-$as_echo "$cross_compiling" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $cross_compiling" >&5
+printf "%s\n" "$cross_compiling" >&6; }
 
-rm -f conftest.$ac_ext conftest$ac_cv_exeext conftest.out
+rm -f conftest.$ac_ext conftest$ac_cv_exeext \
+  conftest.o conftest.obj conftest.out
 ac_clean_files=$ac_clean_files_save
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for suffix of object files" >&5
-$as_echo_n "checking for suffix of object files... " >&6; }
-if ${ac_cv_objext+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for suffix of object files" >&5
+printf %s "checking for suffix of object files... " >&6; }
+if test ${ac_cv_objext+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3513,11 +4107,12 @@
   *) ac_try_echo=$ac_try;;
 esac
 eval ac_try_echo="\"\$as_me:${as_lineno-$LINENO}: $ac_try_echo\""
-$as_echo "$ac_try_echo"; } >&5
+printf "%s\n" "$ac_try_echo"; } >&5
   (eval "$ac_compile") 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
-  test $ac_status = 0; }; then :
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }
+then :
   for ac_file in conftest.o conftest.obj conftest.*; do
   test -f "$ac_file" || continue;
   case $ac_file in
@@ -3526,31 +4121,34 @@
        break;;
   esac
 done
-else
-  $as_echo "$as_me: failed program was:" >&5
+else case e in #(
+  e) printf "%s\n" "$as_me: failed program was:" >&5
 sed 's/^/| /' conftest.$ac_ext >&5
 
-{ { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+{ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "cannot compute suffix of object files: cannot compile
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; } ;;
+esac
 fi
-rm -f conftest.$ac_cv_objext conftest.$ac_ext
+rm -f conftest.$ac_cv_objext conftest.$ac_ext ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_objext" >&5
-$as_echo "$ac_cv_objext" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_objext" >&5
+printf "%s\n" "$ac_cv_objext" >&6; }
 OBJEXT=$ac_cv_objext
 ac_objext=$OBJEXT
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether we are using the GNU C compiler" >&5
-$as_echo_n "checking whether we are using the GNU C compiler... " >&6; }
-if ${ac_cv_c_compiler_gnu+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the compiler supports GNU C" >&5
+printf %s "checking whether the compiler supports GNU C... " >&6; }
+if test ${ac_cv_c_compiler_gnu+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 #ifndef __GNUC__
        choke me
@@ -3560,30 +4158,36 @@
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_compiler_gnu=yes
-else
-  ac_compiler_gnu=no
+else case e in #(
+  e) ac_compiler_gnu=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 ac_cv_c_compiler_gnu=$ac_compiler_gnu
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_compiler_gnu" >&5
-$as_echo "$ac_cv_c_compiler_gnu" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_compiler_gnu" >&5
+printf "%s\n" "$ac_cv_c_compiler_gnu" >&6; }
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
 if test $ac_compiler_gnu = yes; then
   GCC=yes
 else
   GCC=
 fi
-ac_test_CFLAGS=${CFLAGS+set}
+ac_test_CFLAGS=${CFLAGS+y}
 ac_save_CFLAGS=$CFLAGS
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC accepts -g" >&5
-$as_echo_n "checking whether $CC accepts -g... " >&6; }
-if ${ac_cv_prog_cc_g+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_save_c_werror_flag=$ac_c_werror_flag
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC accepts -g" >&5
+printf %s "checking whether $CC accepts -g... " >&6; }
+if test ${ac_cv_prog_cc_g+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_save_c_werror_flag=$ac_c_werror_flag
    ac_c_werror_flag=yes
    ac_cv_prog_cc_g=no
    CFLAGS="-g"
@@ -3591,57 +4195,63 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_g=yes
-else
-  CFLAGS=""
+else case e in #(
+  e) CFLAGS=""
       cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
 
-else
-  ac_c_werror_flag=$ac_save_c_werror_flag
+else case e in #(
+  e) ac_c_werror_flag=$ac_save_c_werror_flag
 	 CFLAGS="-g"
 	 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_g=yes
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-   ac_c_werror_flag=$ac_save_c_werror_flag
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
+   ac_c_werror_flag=$ac_save_c_werror_flag ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_g" >&5
-$as_echo "$ac_cv_prog_cc_g" >&6; }
-if test "$ac_test_CFLAGS" = set; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_g" >&5
+printf "%s\n" "$ac_cv_prog_cc_g" >&6; }
+if test $ac_test_CFLAGS; then
   CFLAGS=$ac_save_CFLAGS
 elif test $ac_cv_prog_cc_g = yes; then
   if test "$GCC" = yes; then
@@ -3656,94 +4266,153 @@
     CFLAGS=
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $CC option to accept ISO C89" >&5
-$as_echo_n "checking for $CC option to accept ISO C89... " >&6; }
-if ${ac_cv_prog_cc_c89+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_cv_prog_cc_c89=no
+ac_prog_cc_stdc=no
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C11 features" >&5
+printf %s "checking for $CC option to enable C11 features... " >&6; }
+if test ${ac_cv_prog_cc_c11+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_cv_prog_cc_c11=no
 ac_save_CC=$CC
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#include <stdarg.h>
-#include <stdio.h>
-struct stat;
-/* Most of the following tests are stolen from RCS 5.7's src/conf.sh.  */
-struct buf { int x; };
-FILE * (*rcsopen) (struct buf *, struct stat *, int);
-static char *e (p, i)
-     char **p;
-     int i;
-{
-  return p[i];
-}
-static char *f (char * (*g) (char **, int), char **p, ...)
-{
-  char *s;
-  va_list v;
-  va_start (v,p);
-  s = g (p, va_arg (v,int));
-  va_end (v);
-  return s;
-}
-
-/* OSF 4.0 Compaq cc is some sort of almost-ANSI by default.  It has
-   function prototypes and stuff, but not '\xHH' hex character constants.
-   These don't provoke an error unfortunately, instead are silently treated
-   as 'x'.  The following induces an error, until -std is added to get
-   proper ANSI mode.  Curiously '\x00'!='x' always comes out true, for an
-   array size at least.  It's necessary to write '\x00'==0 to get something
-   that's true only with -std.  */
-int osf4_cc_array ['\x00' == 0 ? 1 : -1];
-
-/* IBM C 6 for AIX is almost-ANSI by default, but it replaces macro parameters
-   inside strings and character constants.  */
-#define FOO(x) 'x'
-int xlc6_cc_array[FOO(a) == 'x' ? 1 : -1];
-
-int test (int i, double x);
-struct s1 {int (*f) (int a);};
-struct s2 {int (*f) (double a);};
-int pairnames (int, char **, FILE *(*)(struct buf *, struct stat *, int), int, int);
-int argc;
-char **argv;
-int
-main ()
-{
-return f (e, argv, 0) != argv[0]  ||  f (e, argv, 1) != argv[1];
-  ;
-  return 0;
-}
+$ac_c_conftest_c11_program
 _ACEOF
-for ac_arg in '' -qlanglvl=extc89 -qlanglvl=ansi -std \
-	-Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
+for ac_arg in '' -std=gnu11
 do
   CC="$ac_save_CC $ac_arg"
-  if ac_fn_c_try_compile "$LINENO"; then :
+  if ac_fn_c_try_compile "$LINENO"
+then :
+  ac_cv_prog_cc_c11=$ac_arg
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam
+  test "x$ac_cv_prog_cc_c11" != "xno" && break
+done
+rm -f conftest.$ac_ext
+CC=$ac_save_CC ;;
+esac
+fi
+
+if test "x$ac_cv_prog_cc_c11" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else case e in #(
+  e) if test "x$ac_cv_prog_cc_c11" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c11" >&5
+printf "%s\n" "$ac_cv_prog_cc_c11" >&6; }
+     CC="$CC $ac_cv_prog_cc_c11" ;;
+esac
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c11
+  ac_prog_cc_stdc=c11 ;;
+esac
+fi
+fi
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C99 features" >&5
+printf %s "checking for $CC option to enable C99 features... " >&6; }
+if test ${ac_cv_prog_cc_c99+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_cv_prog_cc_c99=no
+ac_save_CC=$CC
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+$ac_c_conftest_c99_program
+_ACEOF
+for ac_arg in '' -std=gnu99 -std=c99 -c99 -qlanglvl=extc1x -qlanglvl=extc99 -AC99 -D_STDC_C99=
+do
+  CC="$ac_save_CC $ac_arg"
+  if ac_fn_c_try_compile "$LINENO"
+then :
+  ac_cv_prog_cc_c99=$ac_arg
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam
+  test "x$ac_cv_prog_cc_c99" != "xno" && break
+done
+rm -f conftest.$ac_ext
+CC=$ac_save_CC ;;
+esac
+fi
+
+if test "x$ac_cv_prog_cc_c99" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else case e in #(
+  e) if test "x$ac_cv_prog_cc_c99" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c99" >&5
+printf "%s\n" "$ac_cv_prog_cc_c99" >&6; }
+     CC="$CC $ac_cv_prog_cc_c99" ;;
+esac
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c99
+  ac_prog_cc_stdc=c99 ;;
+esac
+fi
+fi
+if test x$ac_prog_cc_stdc = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $CC option to enable C89 features" >&5
+printf %s "checking for $CC option to enable C89 features... " >&6; }
+if test ${ac_cv_prog_cc_c89+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_cv_prog_cc_c89=no
+ac_save_CC=$CC
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+$ac_c_conftest_c89_program
+_ACEOF
+for ac_arg in '' -qlanglvl=extc89 -qlanglvl=ansi -std -Ae "-Aa -D_HPUX_SOURCE" "-Xc -D__EXTENSIONS__"
+do
+  CC="$ac_save_CC $ac_arg"
+  if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_prog_cc_c89=$ac_arg
 fi
-rm -f core conftest.err conftest.$ac_objext
+rm -f core conftest.err conftest.$ac_objext conftest.beam
   test "x$ac_cv_prog_cc_c89" != "xno" && break
 done
 rm -f conftest.$ac_ext
-CC=$ac_save_CC
-
-fi
-# AC_CACHE_VAL
-case "x$ac_cv_prog_cc_c89" in
-  x)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
-$as_echo "none needed" >&6; } ;;
-  xno)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
-$as_echo "unsupported" >&6; } ;;
-  *)
-    CC="$CC $ac_cv_prog_cc_c89"
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c89" >&5
-$as_echo "$ac_cv_prog_cc_c89" >&6; } ;;
+CC=$ac_save_CC ;;
 esac
-if test "x$ac_cv_prog_cc_c89" != xno; then :
+fi
 
+if test "x$ac_cv_prog_cc_c89" = xno
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: unsupported" >&5
+printf "%s\n" "unsupported" >&6; }
+else case e in #(
+  e) if test "x$ac_cv_prog_cc_c89" = x
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none needed" >&5
+printf "%s\n" "none needed" >&6; }
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_prog_cc_c89" >&5
+printf "%s\n" "$ac_cv_prog_cc_c89" >&6; }
+     CC="$CC $ac_cv_prog_cc_c89" ;;
+esac
+fi
+  ac_cv_prog_cc_stdc=$ac_cv_prog_cc_c89
+  ac_prog_cc_stdc=c89 ;;
+esac
+fi
 fi
 
 ac_ext=c
@@ -3752,21 +4421,23 @@
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
-ac_ext=c
+
+  ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether $CC understands -c and -o together" >&5
-$as_echo_n "checking whether $CC understands -c and -o together... " >&6; }
-if ${am_cv_prog_cc_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC understands -c and -o together" >&5
+printf %s "checking whether $CC understands -c and -o together... " >&6; }
+if test ${am_cv_prog_cc_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
@@ -3792,10 +4463,11 @@
     fi
   done
   rm -f core conftest*
-  unset am_i
+  unset am_i ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_prog_cc_c_o" >&5
-$as_echo "$am_cv_prog_cc_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_prog_cc_c_o" >&5
+printf "%s\n" "$am_cv_prog_cc_c_o" >&6; }
 if test "$am_cv_prog_cc_c_o" != yes; then
    # Losing compiler, so override with the script.
    # FIXME: It is wrong to rewrite CC.
@@ -3814,8 +4486,8 @@
 
 ac_config_commands="$ac_config_commands depfiles"
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
-$as_echo_n "checking whether ${MAKE-make} supports the include directive... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
+printf %s "checking whether ${MAKE-make} supports the include directive... " >&6; }
 cat > confinc.mk << 'END'
 am__doit:
 	@echo this is the am__doit target >confinc.out
@@ -3851,11 +4523,12 @@
   fi
 done
 rm -f confinc.* confmf.*
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
-$as_echo "${_am_result}" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
+printf "%s\n" "${_am_result}" >&6; }
 
 # Check whether --enable-dependency-tracking was given.
-if test "${enable_dependency_tracking+set}" = set; then :
+if test ${enable_dependency_tracking+y}
+then :
   enableval=$enable_dependency_tracking;
 fi
 
@@ -3876,12 +4549,13 @@
 
 depcc="$CC"   am_compiler_list=
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CC_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
+printf %s "checking dependency style of $depcc... " >&6; }
+if test ${am_cv_CC_dependencies_compiler_type+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
   # We make a subdir and do the tests there.  Otherwise we can end up
   # making bogus files that we don't know about and never remove.  For
   # instance it was reported that on HP-UX the gcc test will end up
@@ -3985,10 +4659,11 @@
 else
   am_cv_CC_dependencies_compiler_type=none
 fi
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CC_dependencies_compiler_type" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_CC_dependencies_compiler_type" >&5
+printf "%s\n" "$am_cv_CC_dependencies_compiler_type" >&6; }
 CCDEPMODE=depmode=$am_cv_CC_dependencies_compiler_type
 
  if
@@ -4011,12 +4686,13 @@
 
 depcc="$CCAS"   am_compiler_list=
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
-$as_echo_n "checking dependency style of $depcc... " >&6; }
-if ${am_cv_CCAS_dependencies_compiler_type+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dependency style of $depcc" >&5
+printf %s "checking dependency style of $depcc... " >&6; }
+if test ${am_cv_CCAS_dependencies_compiler_type+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -z "$AMDEP_TRUE" && test -f "$am_depcomp"; then
   # We make a subdir and do the tests there.  Otherwise we can end up
   # making bogus files that we don't know about and never remove.  For
   # instance it was reported that on HP-UX the gcc test will end up
@@ -4118,10 +4794,11 @@
 else
   am_cv_CCAS_dependencies_compiler_type=none
 fi
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $am_cv_CCAS_dependencies_compiler_type" >&5
-$as_echo "$am_cv_CCAS_dependencies_compiler_type" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $am_cv_CCAS_dependencies_compiler_type" >&5
+printf "%s\n" "$am_cv_CCAS_dependencies_compiler_type" >&6; }
 CCASDEPMODE=depmode=$am_cv_CCAS_dependencies_compiler_type
 
  if
@@ -4135,26 +4812,30 @@
 fi
 
 
-# Make sure we can run config.sub.
-$SHELL "$ac_aux_dir/config.sub" sun4 >/dev/null 2>&1 ||
-  as_fn_error $? "cannot run $SHELL $ac_aux_dir/config.sub" "$LINENO" 5
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
-$as_echo_n "checking build system type... " >&6; }
-if ${ac_cv_build+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_build_alias=$build_alias
+
+  # Make sure we can run config.sub.
+$SHELL "${ac_aux_dir}config.sub" sun4 >/dev/null 2>&1 ||
+  as_fn_error $? "cannot run $SHELL ${ac_aux_dir}config.sub" "$LINENO" 5
+
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking build system type" >&5
+printf %s "checking build system type... " >&6; }
+if test ${ac_cv_build+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_build_alias=$build_alias
 test "x$ac_build_alias" = x &&
-  ac_build_alias=`$SHELL "$ac_aux_dir/config.guess"`
+  ac_build_alias=`$SHELL "${ac_aux_dir}config.guess"`
 test "x$ac_build_alias" = x &&
   as_fn_error $? "cannot guess build type; you must specify one" "$LINENO" 5
-ac_cv_build=`$SHELL "$ac_aux_dir/config.sub" $ac_build_alias` ||
-  as_fn_error $? "$SHELL $ac_aux_dir/config.sub $ac_build_alias failed" "$LINENO" 5
-
+ac_cv_build=`$SHELL "${ac_aux_dir}config.sub" $ac_build_alias` ||
+  as_fn_error $? "$SHELL ${ac_aux_dir}config.sub $ac_build_alias failed" "$LINENO" 5
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
-$as_echo "$ac_cv_build" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_build" >&5
+printf "%s\n" "$ac_cv_build" >&6; }
 case $ac_cv_build in
 *-*-*) ;;
 *) as_fn_error $? "invalid value of canonical build" "$LINENO" 5;;
@@ -4173,21 +4854,23 @@
 case $build_os in *\ *) build_os=`echo "$build_os" | sed 's/ /-/g'`;; esac
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
-$as_echo_n "checking host system type... " >&6; }
-if ${ac_cv_host+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test "x$host_alias" = x; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking host system type" >&5
+printf %s "checking host system type... " >&6; }
+if test ${ac_cv_host+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test "x$host_alias" = x; then
   ac_cv_host=$ac_cv_build
 else
-  ac_cv_host=`$SHELL "$ac_aux_dir/config.sub" $host_alias` ||
-    as_fn_error $? "$SHELL $ac_aux_dir/config.sub $host_alias failed" "$LINENO" 5
+  ac_cv_host=`$SHELL "${ac_aux_dir}config.sub" $host_alias` ||
+    as_fn_error $? "$SHELL ${ac_aux_dir}config.sub $host_alias failed" "$LINENO" 5
 fi
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
-$as_echo "$ac_cv_host" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_host" >&5
+printf "%s\n" "$ac_cv_host" >&6; }
 case $ac_cv_host in
 *-*-*) ;;
 *) as_fn_error $? "invalid value of canonical host" "$LINENO" 5;;
@@ -4206,12 +4889,13 @@
 case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a sed that does not truncate output" >&5
-$as_echo_n "checking for a sed that does not truncate output... " >&6; }
-if ${ac_cv_path_SED+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-            ac_script=s/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb/
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a sed that does not truncate output" >&5
+printf %s "checking for a sed that does not truncate output... " >&6; }
+if test ${ac_cv_path_SED+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e)           ac_script=s/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb/
      for ac_i in 1 2 3 4 5 6 7; do
        ac_script="$ac_script$as_nl$ac_script"
      done
@@ -4224,25 +4908,31 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in sed gsed; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in sed gsed
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_SED="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_SED="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_SED" || continue
 # Check for GNU ac_path_SED and select it if it is found.
   # Check for GNU $ac_path_SED
-case `"$ac_path_SED" --version 2>&1` in
+case `"$ac_path_SED" --version 2>&1` in #(
 *GNU*)
   ac_cv_path_SED="$ac_path_SED" ac_path_SED_found=:;;
+#(
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo '' >> "conftest.nl"
+    printf "%s\n" '' >> "conftest.nl"
     "$ac_path_SED" -f conftest.sed < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4268,10 +4958,11 @@
 else
   ac_cv_path_SED=$SED
 fi
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_SED" >&5
-$as_echo "$ac_cv_path_SED" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_SED" >&5
+printf "%s\n" "$ac_cv_path_SED" >&6; }
  SED="$ac_cv_path_SED"
   rm -f conftest.sed
 
@@ -4288,37 +4979,44 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for grep that handles long lines and -e" >&5
-$as_echo_n "checking for grep that handles long lines and -e... " >&6; }
-if ${ac_cv_path_GREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -z "$GREP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for grep that handles long lines and -e" >&5
+printf %s "checking for grep that handles long lines and -e... " >&6; }
+if test ${ac_cv_path_GREP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -z "$GREP"; then
   ac_path_GREP_found=false
   # Loop through the user's path and test for each of PROGNAME-LIST
   as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in grep ggrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in grep ggrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_GREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_GREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_GREP" || continue
 # Check for GNU ac_path_GREP and select it if it is found.
   # Check for GNU $ac_path_GREP
-case `"$ac_path_GREP" --version 2>&1` in
+case `"$ac_path_GREP" --version 2>&1` in #(
 *GNU*)
   ac_cv_path_GREP="$ac_path_GREP" ac_path_GREP_found=:;;
+#(
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'GREP' >> "conftest.nl"
+    printf "%s\n" 'GREP' >> "conftest.nl"
     "$ac_path_GREP" -e 'GREP$' -e '-(cannot match)-' < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4344,19 +5042,21 @@
 else
   ac_cv_path_GREP=$GREP
 fi
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_GREP" >&5
-$as_echo "$ac_cv_path_GREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_GREP" >&5
+printf "%s\n" "$ac_cv_path_GREP" >&6; }
  GREP="$ac_cv_path_GREP"
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for egrep" >&5
-$as_echo_n "checking for egrep... " >&6; }
-if ${ac_cv_path_EGREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if echo a | $GREP -E '(a|b)' >/dev/null 2>&1
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for egrep" >&5
+printf %s "checking for egrep... " >&6; }
+if test ${ac_cv_path_EGREP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if echo a | $GREP -E '(a|b)' >/dev/null 2>&1
    then ac_cv_path_EGREP="$GREP -E"
    else
      if test -z "$EGREP"; then
@@ -4366,25 +5066,31 @@
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in egrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in egrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_EGREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_EGREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_EGREP" || continue
 # Check for GNU ac_path_EGREP and select it if it is found.
   # Check for GNU $ac_path_EGREP
-case `"$ac_path_EGREP" --version 2>&1` in
+case `"$ac_path_EGREP" --version 2>&1` in #(
 *GNU*)
   ac_cv_path_EGREP="$ac_path_EGREP" ac_path_EGREP_found=:;;
+#(
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'EGREP' >> "conftest.nl"
+    printf "%s\n" 'EGREP' >> "conftest.nl"
     "$ac_path_EGREP" 'EGREP$' < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4411,19 +5117,23 @@
   ac_cv_path_EGREP=$EGREP
 fi
 
-   fi
+   fi ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_EGREP" >&5
-$as_echo "$ac_cv_path_EGREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_EGREP" >&5
+printf "%s\n" "$ac_cv_path_EGREP" >&6; }
  EGREP="$ac_cv_path_EGREP"
 
+         EGREP_TRADITIONAL=$EGREP
+ ac_cv_path_EGREP_TRADITIONAL=$EGREP
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for fgrep" >&5
-$as_echo_n "checking for fgrep... " >&6; }
-if ${ac_cv_path_FGREP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if echo 'ab*c' | $GREP -F 'ab*c' >/dev/null 2>&1
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for fgrep" >&5
+printf %s "checking for fgrep... " >&6; }
+if test ${ac_cv_path_FGREP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if echo 'ab*c' | $GREP -F 'ab*c' >/dev/null 2>&1
    then ac_cv_path_FGREP="$GREP -F"
    else
      if test -z "$FGREP"; then
@@ -4433,25 +5143,31 @@
 for as_dir in $PATH$PATH_SEPARATOR/usr/xpg4/bin
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in fgrep; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in fgrep
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_FGREP="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_FGREP="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_FGREP" || continue
 # Check for GNU ac_path_FGREP and select it if it is found.
   # Check for GNU $ac_path_FGREP
-case `"$ac_path_FGREP" --version 2>&1` in
+case `"$ac_path_FGREP" --version 2>&1` in #(
 *GNU*)
   ac_cv_path_FGREP="$ac_path_FGREP" ac_path_FGREP_found=:;;
+#(
 *)
   ac_count=0
-  $as_echo_n 0123456789 >"conftest.in"
+  printf %s 0123456789 >"conftest.in"
   while :
   do
     cat "conftest.in" "conftest.in" >"conftest.tmp"
     mv "conftest.tmp" "conftest.in"
     cp "conftest.in" "conftest.nl"
-    $as_echo 'FGREP' >> "conftest.nl"
+    printf "%s\n" 'FGREP' >> "conftest.nl"
     "$ac_path_FGREP" FGREP < "conftest.nl" >"conftest.out" 2>/dev/null || break
     diff "conftest.out" "conftest.nl" >/dev/null 2>&1 || break
     as_fn_arith $ac_count + 1 && ac_count=$as_val
@@ -4478,10 +5194,11 @@
   ac_cv_path_FGREP=$FGREP
 fi
 
-   fi
+   fi ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_FGREP" >&5
-$as_echo "$ac_cv_path_FGREP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_FGREP" >&5
+printf "%s\n" "$ac_cv_path_FGREP" >&6; }
  FGREP="$ac_cv_path_FGREP"
 
 
@@ -4507,8 +5224,8 @@
 ECHO=$ECHO$ECHO$ECHO$ECHO$ECHO
 ECHO=$ECHO$ECHO$ECHO$ECHO$ECHO$ECHO
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to print strings" >&5
-$as_echo_n "checking how to print strings... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to print strings" >&5
+printf %s "checking how to print strings... " >&6; }
 # Test print first, because it will be a builtin if present.
 if test "X`( print -r -- -n ) 2>/dev/null`" = X-n && \
    test "X`print -r -- $ECHO 2>/dev/null`" = "X$ECHO"; then
@@ -4534,12 +5251,12 @@
 }
 
 case $ECHO in
-  printf*) { $as_echo "$as_me:${as_lineno-$LINENO}: result: printf" >&5
-$as_echo "printf" >&6; } ;;
-  print*) { $as_echo "$as_me:${as_lineno-$LINENO}: result: print -r" >&5
-$as_echo "print -r" >&6; } ;;
-  *) { $as_echo "$as_me:${as_lineno-$LINENO}: result: cat" >&5
-$as_echo "cat" >&6; } ;;
+  printf*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: printf" >&5
+printf "%s\n" "printf" >&6; } ;;
+  print*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: print -r" >&5
+printf "%s\n" "print -r" >&6; } ;;
+  *) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: cat" >&5
+printf "%s\n" "cat" >&6; } ;;
 esac
 
 
@@ -4558,17 +5275,19 @@
 
 
 # Check whether --with-gnu-ld was given.
-if test "${with_gnu_ld+set}" = set; then :
+if test ${with_gnu_ld+y}
+then :
   withval=$with_gnu_ld; test no = "$withval" || with_gnu_ld=yes
-else
-  with_gnu_ld=no
+else case e in #(
+  e) with_gnu_ld=no ;;
+esac
 fi
 
 ac_prog=ld
 if test yes = "$GCC"; then
   # Check if gcc -print-prog-name=ld gives a path.
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ld used by $CC" >&5
-$as_echo_n "checking for ld used by $CC... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ld used by $CC" >&5
+printf %s "checking for ld used by $CC... " >&6; }
   case $host in
   *-*-mingw*)
     # gcc leaves a trailing carriage return, which upsets mingw
@@ -4597,16 +5316,17 @@
     ;;
   esac
 elif test yes = "$with_gnu_ld"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for GNU ld" >&5
-$as_echo_n "checking for GNU ld... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for GNU ld" >&5
+printf %s "checking for GNU ld... " >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for non-GNU ld" >&5
-$as_echo_n "checking for non-GNU ld... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for non-GNU ld" >&5
+printf %s "checking for non-GNU ld... " >&6; }
 fi
-if ${lt_cv_path_LD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -z "$LD"; then
+if test ${lt_cv_path_LD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -z "$LD"; then
   lt_save_ifs=$IFS; IFS=$PATH_SEPARATOR
   for ac_dir in $PATH; do
     IFS=$lt_save_ifs
@@ -4629,24 +5349,26 @@
   IFS=$lt_save_ifs
 else
   lt_cv_path_LD=$LD # Let the user override the test with a path.
-fi
+fi ;;
+esac
 fi
 
 LD=$lt_cv_path_LD
 if test -n "$LD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $LD" >&5
-$as_echo "$LD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $LD" >&5
+printf "%s\n" "$LD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 test -z "$LD" && as_fn_error $? "no acceptable ld found in \$PATH" "$LINENO" 5
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if the linker ($LD) is GNU ld" >&5
-$as_echo_n "checking if the linker ($LD) is GNU ld... " >&6; }
-if ${lt_cv_prog_gnu_ld+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  # I'd rather use --version here, but apparently some GNU lds only accept -v.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if the linker ($LD) is GNU ld" >&5
+printf %s "checking if the linker ($LD) is GNU ld... " >&6; }
+if test ${lt_cv_prog_gnu_ld+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) # I'd rather use --version here, but apparently some GNU lds only accept -v.
 case `$LD -v 2>&1 </dev/null` in
 *GNU* | *'with BFD'*)
   lt_cv_prog_gnu_ld=yes
@@ -4654,10 +5376,11 @@
 *)
   lt_cv_prog_gnu_ld=no
   ;;
+esac ;;
 esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_gnu_ld" >&5
-$as_echo "$lt_cv_prog_gnu_ld" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_gnu_ld" >&5
+printf "%s\n" "$lt_cv_prog_gnu_ld" >&6; }
 with_gnu_ld=$lt_cv_prog_gnu_ld
 
 
@@ -4673,42 +5396,39 @@
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to run the C preprocessor" >&5
-$as_echo_n "checking how to run the C preprocessor... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to run the C preprocessor" >&5
+printf %s "checking how to run the C preprocessor... " >&6; }
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
 fi
 if test -z "$CPP"; then
-  if ${ac_cv_prog_CPP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-      # Double quotes because CPP needs to be expanded
-    for CPP in "$CC -E" "$CC -E -traditional-cpp" "/lib/cpp"
+  if test ${ac_cv_prog_CPP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e)     # Double quotes because $CC needs to be expanded
+    for CPP in "$CC -E" "$CC -E -traditional-cpp" cpp /lib/cpp
     do
       ac_preproc_ok=false
 for ac_c_preproc_warn_flag in '' yes
 do
   # Use a header file that comes with gcc, so configuring glibc
   # with a fresh cross-compiler works.
-  # Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-  # <limits.h> exists even on freestanding compilers.
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp. "Syntax error" is here to catch this case.
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
+#include <limits.h>
 		     Syntax error
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
 
-else
-  # Broken: fails on valid input.
-continue
+else case e in #(
+  e) # Broken: fails on valid input.
+continue ;;
+esac
 fi
 rm -f conftest.err conftest.i conftest.$ac_ext
 
@@ -4718,56 +5438,56 @@
 /* end confdefs.h.  */
 #include <ac_nonexistent.h>
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
   # Broken: success on invalid input.
 continue
-else
-  # Passes both tests.
+else case e in #(
+  e) # Passes both tests.
 ac_preproc_ok=:
-break
+break ;;
+esac
 fi
 rm -f conftest.err conftest.i conftest.$ac_ext
 
 done
-# Because of `break', _AC_PREPROC_IFELSE's cleaning code was skipped.
+# Because of 'break', _AC_PREPROC_IFELSE's cleaning code was skipped.
 rm -f conftest.i conftest.err conftest.$ac_ext
-if $ac_preproc_ok; then :
+if $ac_preproc_ok
+then :
   break
 fi
 
     done
     ac_cv_prog_CPP=$CPP
-
+   ;;
+esac
 fi
   CPP=$ac_cv_prog_CPP
 else
   ac_cv_prog_CPP=$CPP
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $CPP" >&5
-$as_echo "$CPP" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $CPP" >&5
+printf "%s\n" "$CPP" >&6; }
 ac_preproc_ok=false
 for ac_c_preproc_warn_flag in '' yes
 do
   # Use a header file that comes with gcc, so configuring glibc
   # with a fresh cross-compiler works.
-  # Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
-  # <limits.h> exists even on freestanding compilers.
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp. "Syntax error" is here to catch this case.
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-#ifdef __STDC__
-# include <limits.h>
-#else
-# include <assert.h>
-#endif
+#include <limits.h>
 		     Syntax error
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
 
-else
-  # Broken: fails on valid input.
-continue
+else case e in #(
+  e) # Broken: fails on valid input.
+continue ;;
+esac
 fi
 rm -f conftest.err conftest.i conftest.$ac_ext
 
@@ -4777,26 +5497,30 @@
 /* end confdefs.h.  */
 #include <ac_nonexistent.h>
 _ACEOF
-if ac_fn_c_try_cpp "$LINENO"; then :
+if ac_fn_c_try_cpp "$LINENO"
+then :
   # Broken: success on invalid input.
 continue
-else
-  # Passes both tests.
+else case e in #(
+  e) # Passes both tests.
 ac_preproc_ok=:
-break
+break ;;
+esac
 fi
 rm -f conftest.err conftest.i conftest.$ac_ext
 
 done
-# Because of `break', _AC_PREPROC_IFELSE's cleaning code was skipped.
+# Because of 'break', _AC_PREPROC_IFELSE's cleaning code was skipped.
 rm -f conftest.i conftest.err conftest.$ac_ext
-if $ac_preproc_ok; then :
+if $ac_preproc_ok
+then :
 
-else
-  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+else case e in #(
+  e) { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "C preprocessor \"$CPP\" fails sanity check
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; } ;;
+esac
 fi
 
 ac_ext=c
@@ -4809,38 +5533,44 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AWK+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$AWK"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AWK+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$AWK"; then
   ac_cv_prog_AWK="$AWK" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AWK="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 AWK=$ac_cv_prog_AWK
 if test -n "$AWK"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
-$as_echo "$AWK" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AWK" >&5
+printf "%s\n" "$AWK" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -4848,25 +5578,26 @@
 done
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ln -s works" >&5
-$as_echo_n "checking whether ln -s works... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ln -s works" >&5
+printf %s "checking whether ln -s works... " >&6; }
 LN_S=$as_ln_s
 if test "$LN_S" = "ln -s"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no, using $LN_S" >&5
-$as_echo "no, using $LN_S" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no, using $LN_S" >&5
+printf "%s\n" "no, using $LN_S" >&6; }
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
-$as_echo_n "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} sets \$(MAKE)" >&5
+printf %s "checking whether ${MAKE-make} sets \$(MAKE)... " >&6; }
 set x ${MAKE-make}
-ac_make=`$as_echo "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
-if eval \${ac_cv_prog_make_${ac_make}_set+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat >conftest.make <<\_ACEOF
+ac_make=`printf "%s\n" "$2" | sed 's/+/p/g; s/[^a-zA-Z0-9_]/_/g'`
+if eval test \${ac_cv_prog_make_${ac_make}_set+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat >conftest.make <<\_ACEOF
 SHELL = /bin/sh
 all:
 	@echo '@@@%%%=$(MAKE)=@@@%%%'
@@ -4878,29 +5609,31 @@
   *)
     eval ac_cv_prog_make_${ac_make}_set=no;;
 esac
-rm -f conftest.make
+rm -f conftest.make ;;
+esac
 fi
 if eval test \$ac_cv_prog_make_${ac_make}_set = yes; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
   SET_MAKE=
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
   SET_MAKE="MAKE=${MAKE-make}"
 fi
 
 
 case `pwd` in
   *\ * | *\	*)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&5
-$as_echo "$as_me: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&2;} ;;
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&5
+printf "%s\n" "$as_me: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&2;} ;;
 esac
 
 
 
-macro_version='2.4.6'
-macro_revision='2.4.6'
+macro_version='2.4.7'
+macro_revision='2.4.7'
+
 
 
 
@@ -4933,12 +5666,13 @@
 # Sed substitution to avoid accidental globbing in evaled expressions
 no_glob_subst='s/\*/\\\*/g'
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for BSD- or MS-compatible name lister (nm)" >&5
-$as_echo_n "checking for BSD- or MS-compatible name lister (nm)... " >&6; }
-if ${lt_cv_path_NM+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$NM"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for BSD- or MS-compatible name lister (nm)" >&5
+printf %s "checking for BSD- or MS-compatible name lister (nm)... " >&6; }
+if test ${lt_cv_path_NM+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$NM"; then
   # Let the user override the test.
   lt_cv_path_NM=$NM
 else
@@ -4962,13 +5696,13 @@
 	mingw*) lt_bad_file=conftest.nm/nofile ;;
 	*) lt_bad_file=/dev/null ;;
 	esac
-	case `"$tmp_nm" -B $lt_bad_file 2>&1 | sed '1q'` in
+	case `"$tmp_nm" -B $lt_bad_file 2>&1 | $SED '1q'` in
 	*$lt_bad_file* | *'Invalid file or object type'*)
 	  lt_cv_path_NM="$tmp_nm -B"
 	  break 2
 	  ;;
 	*)
-	  case `"$tmp_nm" -p /dev/null 2>&1 | sed '1q'` in
+	  case `"$tmp_nm" -p /dev/null 2>&1 | $SED '1q'` in
 	  */dev/null*)
 	    lt_cv_path_NM="$tmp_nm -p"
 	    break 2
@@ -4985,10 +5719,11 @@
     IFS=$lt_save_ifs
   done
   : ${lt_cv_path_NM=no}
+fi ;;
+esac
 fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_NM" >&5
-$as_echo "$lt_cv_path_NM" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_NM" >&5
+printf "%s\n" "$lt_cv_path_NM" >&6; }
 if test no != "$lt_cv_path_NM"; then
   NM=$lt_cv_path_NM
 else
@@ -5001,38 +5736,44 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DUMPBIN+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$DUMPBIN"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DUMPBIN+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$DUMPBIN"; then
   ac_cv_prog_DUMPBIN="$DUMPBIN" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DUMPBIN="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 DUMPBIN=$ac_cv_prog_DUMPBIN
 if test -n "$DUMPBIN"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DUMPBIN" >&5
-$as_echo "$DUMPBIN" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DUMPBIN" >&5
+printf "%s\n" "$DUMPBIN" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5045,38 +5786,44 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DUMPBIN+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_DUMPBIN"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DUMPBIN+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_DUMPBIN"; then
   ac_cv_prog_ac_ct_DUMPBIN="$ac_ct_DUMPBIN" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DUMPBIN="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_DUMPBIN=$ac_cv_prog_ac_ct_DUMPBIN
 if test -n "$ac_ct_DUMPBIN"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DUMPBIN" >&5
-$as_echo "$ac_ct_DUMPBIN" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DUMPBIN" >&5
+printf "%s\n" "$ac_ct_DUMPBIN" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5088,15 +5835,15 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DUMPBIN=$ac_ct_DUMPBIN
   fi
 fi
 
-    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | sed '1q'` in
+    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | $SED '1q'` in
     *COFF*)
       DUMPBIN="$DUMPBIN -symbols -headers"
       ;;
@@ -5117,12 +5864,13 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the name lister ($NM) interface" >&5
-$as_echo_n "checking the name lister ($NM) interface... " >&6; }
-if ${lt_cv_nm_interface+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_nm_interface="BSD nm"
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking the name lister ($NM) interface" >&5
+printf %s "checking the name lister ($NM) interface... " >&6; }
+if test ${lt_cv_nm_interface+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_nm_interface="BSD nm"
   echo "int some_variable = 0;" > conftest.$ac_ext
   (eval echo "\"\$as_me:$LINENO: $ac_compile\"" >&5)
   (eval "$ac_compile" 2>conftest.err)
@@ -5135,18 +5883,20 @@
   if $GREP 'External.*some_variable' conftest.out > /dev/null; then
     lt_cv_nm_interface="MS dumpbin"
   fi
-  rm -f conftest*
+  rm -f conftest* ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_nm_interface" >&5
-$as_echo "$lt_cv_nm_interface" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_nm_interface" >&5
+printf "%s\n" "$lt_cv_nm_interface" >&6; }
 
 # find the maximum length of command line arguments
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the maximum length of command line arguments" >&5
-$as_echo_n "checking the maximum length of command line arguments... " >&6; }
-if ${lt_cv_sys_max_cmd_len+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-    i=0
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking the maximum length of command line arguments" >&5
+printf %s "checking the maximum length of command line arguments... " >&6; }
+if test ${lt_cv_sys_max_cmd_len+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e)   i=0
   teststring=ABCD
 
   case $build_os in
@@ -5187,7 +5937,7 @@
     lt_cv_sys_max_cmd_len=8192;
     ;;
 
-  bitrig* | darwin* | dragonfly* | freebsd* | netbsd* | openbsd*)
+  bitrig* | darwin* | dragonfly* | freebsd* | midnightbsd* | netbsd* | openbsd*)
     # This has been around since 386BSD, at least.  Likely further.
     if test -x /sbin/sysctl; then
       lt_cv_sys_max_cmd_len=`/sbin/sysctl -n kern.argmax`
@@ -5230,7 +5980,7 @@
   sysv5* | sco5v6* | sysv4.2uw2*)
     kargmax=`grep ARG_MAX /etc/conf/cf.d/stune 2>/dev/null`
     if test -n "$kargmax"; then
-      lt_cv_sys_max_cmd_len=`echo $kargmax | sed 's/.*[	 ]//'`
+      lt_cv_sys_max_cmd_len=`echo $kargmax | $SED 's/.*[	 ]//'`
     else
       lt_cv_sys_max_cmd_len=32768
     fi
@@ -5268,15 +6018,16 @@
     fi
     ;;
   esac
-
+ ;;
+esac
 fi
 
 if test -n "$lt_cv_sys_max_cmd_len"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sys_max_cmd_len" >&5
-$as_echo "$lt_cv_sys_max_cmd_len" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sys_max_cmd_len" >&5
+printf "%s\n" "$lt_cv_sys_max_cmd_len" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: none" >&5
-$as_echo "none" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: none" >&5
+printf "%s\n" "none" >&6; }
 fi
 max_cmd_len=$lt_cv_sys_max_cmd_len
 
@@ -5320,12 +6071,13 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to $host format" >&5
-$as_echo_n "checking how to convert $build file names to $host format... " >&6; }
-if ${lt_cv_to_host_file_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  case $host in
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to $host format" >&5
+printf %s "checking how to convert $build file names to $host format... " >&6; }
+if test ${lt_cv_to_host_file_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) case $host in
   *-*-mingw* )
     case $build in
       *-*-mingw* ) # actually msys
@@ -5356,23 +6108,25 @@
     lt_cv_to_host_file_cmd=func_convert_file_noop
     ;;
 esac
-
+ ;;
+esac
 fi
 
 to_host_file_cmd=$lt_cv_to_host_file_cmd
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_host_file_cmd" >&5
-$as_echo "$lt_cv_to_host_file_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_host_file_cmd" >&5
+printf "%s\n" "$lt_cv_to_host_file_cmd" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to toolchain format" >&5
-$as_echo_n "checking how to convert $build file names to toolchain format... " >&6; }
-if ${lt_cv_to_tool_file_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  #assume ordinary cross tools, or native build.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to convert $build file names to toolchain format" >&5
+printf %s "checking how to convert $build file names to toolchain format... " >&6; }
+if test ${lt_cv_to_tool_file_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) #assume ordinary cross tools, or native build.
 lt_cv_to_tool_file_cmd=func_convert_file_noop
 case $host in
   *-*-mingw* )
@@ -5383,26 +6137,29 @@
     esac
     ;;
 esac
-
+ ;;
+esac
 fi
 
 to_tool_file_cmd=$lt_cv_to_tool_file_cmd
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_tool_file_cmd" >&5
-$as_echo "$lt_cv_to_tool_file_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_to_tool_file_cmd" >&5
+printf "%s\n" "$lt_cv_to_tool_file_cmd" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $LD option to reload object files" >&5
-$as_echo_n "checking for $LD option to reload object files... " >&6; }
-if ${lt_cv_ld_reload_flag+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_ld_reload_flag='-r'
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $LD option to reload object files" >&5
+printf %s "checking for $LD option to reload object files... " >&6; }
+if test ${lt_cv_ld_reload_flag+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_ld_reload_flag='-r' ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_reload_flag" >&5
-$as_echo "$lt_cv_ld_reload_flag" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_reload_flag" >&5
+printf "%s\n" "$lt_cv_ld_reload_flag" >&6; }
 reload_flag=$lt_cv_ld_reload_flag
 case $reload_flag in
 "" | " "*) ;;
@@ -5433,40 +6190,156 @@
 
 
 if test -n "$ac_tool_prefix"; then
-  # Extract the first word of "${ac_tool_prefix}objdump", so it can be a program name with args.
-set dummy ${ac_tool_prefix}objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$OBJDUMP"; then
-  ac_cv_prog_OBJDUMP="$OBJDUMP" # Let the user override the test.
+  # Extract the first word of "${ac_tool_prefix}file", so it can be a program name with args.
+set dummy ${ac_tool_prefix}file; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_FILECMD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$FILECMD"; then
+  ac_cv_prog_FILECMD="$FILECMD" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    ac_cv_prog_OBJDUMP="${ac_tool_prefix}objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_FILECMD="${ac_tool_prefix}file"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
+fi ;;
+esac
 fi
+FILECMD=$ac_cv_prog_FILECMD
+if test -n "$FILECMD"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $FILECMD" >&5
+printf "%s\n" "$FILECMD" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+
+fi
+if test -z "$ac_cv_prog_FILECMD"; then
+  ac_ct_FILECMD=$FILECMD
+  # Extract the first word of "file", so it can be a program name with args.
+set dummy file; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_FILECMD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_FILECMD"; then
+  ac_cv_prog_ac_ct_FILECMD="$ac_ct_FILECMD" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_ac_ct_FILECMD="file"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi ;;
+esac
+fi
+ac_ct_FILECMD=$ac_cv_prog_ac_ct_FILECMD
+if test -n "$ac_ct_FILECMD"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_FILECMD" >&5
+printf "%s\n" "$ac_ct_FILECMD" >&6; }
+else
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+fi
+
+  if test "x$ac_ct_FILECMD" = x; then
+    FILECMD=":"
+  else
+    case $cross_compiling:$ac_tool_warned in
+yes:)
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+ac_tool_warned=yes ;;
+esac
+    FILECMD=$ac_ct_FILECMD
+  fi
+else
+  FILECMD="$ac_cv_prog_FILECMD"
+fi
+
+
+
+
+
+
+
+if test -n "$ac_tool_prefix"; then
+  # Extract the first word of "${ac_tool_prefix}objdump", so it can be a program name with args.
+set dummy ${ac_tool_prefix}objdump; ac_word=$2
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$OBJDUMP"; then
+  ac_cv_prog_OBJDUMP="$OBJDUMP" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+  IFS=$as_save_IFS
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_exec_ext in '' $ac_executable_extensions; do
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
+    ac_cv_prog_OBJDUMP="${ac_tool_prefix}objdump"
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
+    break 2
+  fi
+done
+  done
+IFS=$as_save_IFS
+
+fi ;;
+esac
 fi
 OBJDUMP=$ac_cv_prog_OBJDUMP
 if test -n "$OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
-$as_echo "$OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
+printf "%s\n" "$OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5475,38 +6348,44 @@
   ac_ct_OBJDUMP=$OBJDUMP
   # Extract the first word of "objdump", so it can be a program name with args.
 set dummy objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_OBJDUMP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_OBJDUMP"; then
   ac_cv_prog_ac_ct_OBJDUMP="$ac_ct_OBJDUMP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OBJDUMP="objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_OBJDUMP=$ac_cv_prog_ac_ct_OBJDUMP
 if test -n "$ac_ct_OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
-$as_echo "$ac_ct_OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
+printf "%s\n" "$ac_ct_OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OBJDUMP" = x; then
@@ -5514,8 +6393,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OBJDUMP=$ac_ct_OBJDUMP
@@ -5531,12 +6410,13 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to recognize dependent libraries" >&5
-$as_echo_n "checking how to recognize dependent libraries... " >&6; }
-if ${lt_cv_deplibs_check_method+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_file_magic_cmd='$MAGIC_CMD'
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to recognize dependent libraries" >&5
+printf %s "checking how to recognize dependent libraries... " >&6; }
+if test ${lt_cv_deplibs_check_method+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_file_magic_cmd='$MAGIC_CMD'
 lt_cv_file_magic_test_file=
 lt_cv_deplibs_check_method='unknown'
 # Need to set the preceding variable on all platforms that support
@@ -5561,7 +6441,7 @@
 
 bsdi[45]*)
   lt_cv_deplibs_check_method='file_magic ELF [0-9][0-9]*-bit [ML]SB (shared object|dynamic lib)'
-  lt_cv_file_magic_cmd='/usr/bin/file -L'
+  lt_cv_file_magic_cmd='$FILECMD -L'
   lt_cv_file_magic_test_file=/shlib/libc.so
   ;;
 
@@ -5595,14 +6475,14 @@
   lt_cv_deplibs_check_method=pass_all
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   if echo __ELF__ | $CC -E - | $GREP __ELF__ > /dev/null; then
     case $host_cpu in
     i*86 )
       # Not sure whether the presence of OpenBSD here was a mistake.
       # Let's accept both of them until this is cleared up.
       lt_cv_deplibs_check_method='file_magic (FreeBSD|OpenBSD|DragonFly)/i[3-9]86 (compact )?demand paged shared library'
-      lt_cv_file_magic_cmd=/usr/bin/file
+      lt_cv_file_magic_cmd=$FILECMD
       lt_cv_file_magic_test_file=`echo /usr/lib/libc.so.*`
       ;;
     esac
@@ -5616,7 +6496,7 @@
   ;;
 
 hpux10.20* | hpux11*)
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   case $host_cpu in
   ia64*)
     lt_cv_deplibs_check_method='file_magic (s[0-9][0-9][0-9]|ELF-[0-9][0-9]) shared object file - IA64'
@@ -5663,7 +6543,7 @@
 
 newos6*)
   lt_cv_deplibs_check_method='file_magic ELF [0-9][0-9]*-bit [ML]SB (executable|dynamic lib)'
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   lt_cv_file_magic_test_file=/usr/lib/libnls.so
   ;;
 
@@ -5729,10 +6609,11 @@
   lt_cv_deplibs_check_method=pass_all
   ;;
 esac
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_deplibs_check_method" >&5
-$as_echo "$lt_cv_deplibs_check_method" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_deplibs_check_method" >&5
+printf "%s\n" "$lt_cv_deplibs_check_method" >&6; }
 
 file_magic_glob=
 want_nocaseglob=no
@@ -5776,38 +6657,44 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dlltool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$DLLTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$DLLTOOL"; then
   ac_cv_prog_DLLTOOL="$DLLTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DLLTOOL="${ac_tool_prefix}dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 DLLTOOL=$ac_cv_prog_DLLTOOL
 if test -n "$DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
-$as_echo "$DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
+printf "%s\n" "$DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5816,38 +6703,44 @@
   ac_ct_DLLTOOL=$DLLTOOL
   # Extract the first word of "dlltool", so it can be a program name with args.
 set dummy dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_DLLTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_DLLTOOL"; then
   ac_cv_prog_ac_ct_DLLTOOL="$ac_ct_DLLTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DLLTOOL="dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_DLLTOOL=$ac_cv_prog_ac_ct_DLLTOOL
 if test -n "$ac_ct_DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
-$as_echo "$ac_ct_DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
+printf "%s\n" "$ac_ct_DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DLLTOOL" = x; then
@@ -5855,8 +6748,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DLLTOOL=$ac_ct_DLLTOOL
@@ -5873,12 +6766,13 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to associate runtime and link libraries" >&5
-$as_echo_n "checking how to associate runtime and link libraries... " >&6; }
-if ${lt_cv_sharedlib_from_linklib_cmd+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_sharedlib_from_linklib_cmd='unknown'
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to associate runtime and link libraries" >&5
+printf %s "checking how to associate runtime and link libraries... " >&6; }
+if test ${lt_cv_sharedlib_from_linklib_cmd+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_sharedlib_from_linklib_cmd='unknown'
 
 case $host_os in
 cygwin* | mingw* | pw32* | cegcc*)
@@ -5898,10 +6792,11 @@
   lt_cv_sharedlib_from_linklib_cmd=$ECHO
   ;;
 esac
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sharedlib_from_linklib_cmd" >&5
-$as_echo "$lt_cv_sharedlib_from_linklib_cmd" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_sharedlib_from_linklib_cmd" >&5
+printf "%s\n" "$lt_cv_sharedlib_from_linklib_cmd" >&6; }
 sharedlib_from_linklib_cmd=$lt_cv_sharedlib_from_linklib_cmd
 test -z "$sharedlib_from_linklib_cmd" && sharedlib_from_linklib_cmd=$ECHO
 
@@ -5917,38 +6812,44 @@
   do
     # Extract the first word of "$ac_tool_prefix$ac_prog", so it can be a program name with args.
 set dummy $ac_tool_prefix$ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AR+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$AR"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AR+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$AR"; then
   ac_cv_prog_AR="$AR" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AR="$ac_tool_prefix$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 AR=$ac_cv_prog_AR
 if test -n "$AR"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AR" >&5
-$as_echo "$AR" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AR" >&5
+printf "%s\n" "$AR" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -5961,38 +6862,44 @@
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_AR+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_AR"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_AR+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_AR"; then
   ac_cv_prog_ac_ct_AR="$ac_ct_AR" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_AR="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_AR=$ac_cv_prog_ac_ct_AR
 if test -n "$ac_ct_AR"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AR" >&5
-$as_echo "$ac_ct_AR" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AR" >&5
+printf "%s\n" "$ac_ct_AR" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6004,8 +6911,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     AR=$ac_ct_AR
@@ -6013,42 +6920,60 @@
 fi
 
 : ${AR=ar}
-: ${AR_FLAGS=cru}
 
 
 
 
 
 
+# Use ARFLAGS variable as AR's operation code to sync the variable naming with
+# Automake.  If both AR_FLAGS and ARFLAGS are specified, AR_FLAGS should have
+# higher priority because thats what people were doing historically (setting
+# ARFLAGS for automake and AR_FLAGS for libtool).  FIXME: Make the AR_FLAGS
+# variable obsoleted/removed.
+
+test ${AR_FLAGS+y} || AR_FLAGS=${ARFLAGS-cr}
+lt_ar_flags=$AR_FLAGS
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for archiver @FILE support" >&5
-$as_echo_n "checking for archiver @FILE support... " >&6; }
-if ${lt_cv_ar_at_file+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_ar_at_file=no
+
+# Make AR_FLAGS overridable by 'make ARFLAGS='.  Don't try to run-time override
+# by AR_FLAGS because that was never working and AR_FLAGS is about to die.
+
+
+
+
+
+
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for archiver @FILE support" >&5
+printf %s "checking for archiver @FILE support... " >&6; }
+if test ${lt_cv_ar_at_file+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_ar_at_file=no
    cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   echo conftest.$ac_objext > conftest.lst
       lt_ar_try='$AR $AR_FLAGS libconftest.a @conftest.lst >&5'
       { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$lt_ar_try\""; } >&5
   (eval $lt_ar_try) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
       if test 0 -eq "$ac_status"; then
 	# Ensure the archiver fails upon bogus file names.
@@ -6056,7 +6981,7 @@
 	{ { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$lt_ar_try\""; } >&5
   (eval $lt_ar_try) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 	if test 0 -ne "$ac_status"; then
           lt_cv_ar_at_file=@
@@ -6065,11 +6990,12 @@
       rm -f conftest.* libconftest.a
 
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
+   ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ar_at_file" >&5
-$as_echo "$lt_cv_ar_at_file" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ar_at_file" >&5
+printf "%s\n" "$lt_cv_ar_at_file" >&6; }
 
 if test no = "$lt_cv_ar_at_file"; then
   archiver_list_spec=
@@ -6086,38 +7012,44 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}strip", so it can be a program name with args.
 set dummy ${ac_tool_prefix}strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$STRIP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$STRIP"; then
   ac_cv_prog_STRIP="$STRIP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_STRIP="${ac_tool_prefix}strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 STRIP=$ac_cv_prog_STRIP
 if test -n "$STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
-$as_echo "$STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $STRIP" >&5
+printf "%s\n" "$STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6126,38 +7058,44 @@
   ac_ct_STRIP=$STRIP
   # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_STRIP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_STRIP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_STRIP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_STRIP"; then
   ac_cv_prog_ac_ct_STRIP="$ac_ct_STRIP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_STRIP="strip"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_STRIP=$ac_cv_prog_ac_ct_STRIP
 if test -n "$ac_ct_STRIP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
-$as_echo "$ac_ct_STRIP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_STRIP" >&5
+printf "%s\n" "$ac_ct_STRIP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_STRIP" = x; then
@@ -6165,8 +7103,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     STRIP=$ac_ct_STRIP
@@ -6185,38 +7123,44 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}ranlib", so it can be a program name with args.
 set dummy ${ac_tool_prefix}ranlib; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_RANLIB+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$RANLIB"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_RANLIB+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$RANLIB"; then
   ac_cv_prog_RANLIB="$RANLIB" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_RANLIB="${ac_tool_prefix}ranlib"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 RANLIB=$ac_cv_prog_RANLIB
 if test -n "$RANLIB"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $RANLIB" >&5
-$as_echo "$RANLIB" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $RANLIB" >&5
+printf "%s\n" "$RANLIB" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -6225,38 +7169,44 @@
   ac_ct_RANLIB=$RANLIB
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_RANLIB+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_RANLIB"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_RANLIB+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_RANLIB"; then
   ac_cv_prog_ac_ct_RANLIB="$ac_ct_RANLIB" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_RANLIB="ranlib"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_RANLIB=$ac_cv_prog_ac_ct_RANLIB
 if test -n "$ac_ct_RANLIB"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_RANLIB" >&5
-$as_echo "$ac_ct_RANLIB" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_RANLIB" >&5
+printf "%s\n" "$ac_ct_RANLIB" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_RANLIB" = x; then
@@ -6264,8 +7214,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     RANLIB=$ac_ct_RANLIB
@@ -6354,12 +7304,13 @@
 
 
 # Check for command to grab the raw symbol name followed by C symbol from nm.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking command to parse $NM output from $compiler object" >&5
-$as_echo_n "checking command to parse $NM output from $compiler object... " >&6; }
-if ${lt_cv_sys_global_symbol_pipe+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking command to parse $NM output from $compiler object" >&5
+printf %s "checking command to parse $NM output from $compiler object... " >&6; }
+if test ${lt_cv_sys_global_symbol_pipe+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e)
 # These are sane defaults that work on at least a few old systems.
 # [They come from Ultrix.  What could be older than Ultrix?!! ;)]
 
@@ -6413,7 +7364,7 @@
 
 if test "$lt_cv_nm_interface" = "MS dumpbin"; then
   # Gets list of data symbols to import.
-  lt_cv_sys_global_symbol_to_import="sed -n -e 's/^I .* \(.*\)$/\1/p'"
+  lt_cv_sys_global_symbol_to_import="$SED -n -e 's/^I .* \(.*\)$/\1/p'"
   # Adjust the below global symbol transforms to fixup imported variables.
   lt_cdecl_hook=" -e 's/^I .* \(.*\)$/extern __declspec(dllimport) char \1;/p'"
   lt_c_name_hook=" -e 's/^I .* \(.*\)$/  {\"\1\", (void *) 0},/p'"
@@ -6431,20 +7382,20 @@
 # Transform an extracted symbol line into a proper C declaration.
 # Some systems (esp. on ia64) link data and code symbols differently,
 # so use this general approach.
-lt_cv_sys_global_symbol_to_cdecl="sed -n"\
+lt_cv_sys_global_symbol_to_cdecl="$SED -n"\
 $lt_cdecl_hook\
 " -e 's/^T .* \(.*\)$/extern int \1();/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/extern char \1;/p'"
 
 # Transform an extracted symbol line into symbol name and symbol address
-lt_cv_sys_global_symbol_to_c_name_address="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address="$SED -n"\
 $lt_c_name_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/  {\"\1\", (void *) \&\1},/p'"
 
 # Transform an extracted symbol line into symbol name with lib prefix and
 # symbol address.
-lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="$SED -n"\
 $lt_c_name_lib_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(lib.*\)$/  {\"\1\", (void *) \&\1},/p'"\
@@ -6468,7 +7419,7 @@
   if test "$lt_cv_nm_interface" = "MS dumpbin"; then
     # Fake it for dumpbin and say T for any non-static function,
     # D for any global variable and I for any imported variable.
-    # Also find C++ and __fastcall symbols from MSVC++,
+    # Also find C++ and __fastcall symbols from MSVC++ or ICC,
     # which start with @ or ?.
     lt_cv_sys_global_symbol_pipe="$AWK '"\
 "     {last_section=section; section=\$ 3};"\
@@ -6486,9 +7437,9 @@
 "     s[1]~prfx {split(s[1],t,\"@\"); print f,t[1],substr(t[1],length(prfx))}"\
 "     ' prfx=^$ac_symprfx"
   else
-    lt_cv_sys_global_symbol_pipe="sed -n -e 's/^.*[	 ]\($symcode$symcode*\)[	 ][	 ]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
+    lt_cv_sys_global_symbol_pipe="$SED -n -e 's/^.*[	 ]\($symcode$symcode*\)[	 ][	 ]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
   fi
-  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | sed '/ __gnu_lto/d'"
+  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | $SED '/ __gnu_lto/d'"
 
   # Check to see that the pipe works correctly.
   pipe_works=no
@@ -6510,14 +7461,14 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     # Now try to grab the symbols.
     nlist=conftest.nm
     if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$NM conftest.$ac_objext \| "$lt_cv_sys_global_symbol_pipe" \> $nlist\""; } >&5
   (eval $NM conftest.$ac_objext \| "$lt_cv_sys_global_symbol_pipe" \> $nlist) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "$nlist"; then
       # Try sorting and uniquifying the output.
       if sort "$nlist" | uniq > "$nlist"T; then
@@ -6586,7 +7537,7 @@
 	  if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s conftest$ac_exeext; then
 	    pipe_works=yes
 	  fi
@@ -6614,18 +7565,19 @@
     lt_cv_sys_global_symbol_pipe=
   fi
 done
-
+ ;;
+esac
 fi
 
 if test -z "$lt_cv_sys_global_symbol_pipe"; then
   lt_cv_sys_global_symbol_to_cdecl=
 fi
 if test -z "$lt_cv_sys_global_symbol_pipe$lt_cv_sys_global_symbol_to_cdecl"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: failed" >&5
-$as_echo "failed" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: failed" >&5
+printf "%s\n" "failed" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: ok" >&5
-$as_echo "ok" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ok" >&5
+printf "%s\n" "ok" >&6; }
 fi
 
 # Response file support.
@@ -6671,14 +7623,16 @@
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for sysroot" >&5
-$as_echo_n "checking for sysroot... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for sysroot" >&5
+printf %s "checking for sysroot... " >&6; }
 
 # Check whether --with-sysroot was given.
-if test "${with_sysroot+set}" = set; then :
+if test ${with_sysroot+y}
+then :
   withval=$with_sysroot;
-else
-  with_sysroot=no
+else case e in #(
+  e) with_sysroot=no ;;
+esac
 fi
 
 
@@ -6690,30 +7644,31 @@
    fi
    ;; #(
  /*)
-   lt_sysroot=`echo "$with_sysroot" | sed -e "$sed_quote_subst"`
+   lt_sysroot=`echo "$with_sysroot" | $SED -e "$sed_quote_subst"`
    ;; #(
  no|'')
    ;; #(
  *)
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_sysroot" >&5
-$as_echo "$with_sysroot" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $with_sysroot" >&5
+printf "%s\n" "$with_sysroot" >&6; }
    as_fn_error $? "The sysroot must be an absolute path." "$LINENO" 5
    ;;
 esac
 
- { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${lt_sysroot:-no}" >&5
-$as_echo "${lt_sysroot:-no}" >&6; }
+ { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ${lt_sysroot:-no}" >&5
+printf "%s\n" "${lt_sysroot:-no}" >&6; }
 
 
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a working dd" >&5
-$as_echo_n "checking for a working dd... " >&6; }
-if ${ac_cv_path_lt_DD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  printf 0123456789abcdef0123456789abcdef >conftest.i
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for a working dd" >&5
+printf %s "checking for a working dd... " >&6; }
+if test ${ac_cv_path_lt_DD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) printf 0123456789abcdef0123456789abcdef >conftest.i
 cat conftest.i conftest.i >conftest2.i
 : ${lt_DD:=$DD}
 if test -z "$lt_DD"; then
@@ -6723,10 +7678,15 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in dd; do
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    for ac_prog in dd
+   do
     for ac_exec_ext in '' $ac_executable_extensions; do
-      ac_path_lt_DD="$as_dir/$ac_prog$ac_exec_ext"
+      ac_path_lt_DD="$as_dir$ac_prog$ac_exec_ext"
       as_fn_executable_p "$ac_path_lt_DD" || continue
 if "$ac_path_lt_DD" bs=32 count=1 <conftest2.i >conftest.out 2>/dev/null; then
   cmp -s conftest.i conftest.out \
@@ -6744,18 +7704,20 @@
   ac_cv_path_lt_DD=$lt_DD
 fi
 
-rm -f conftest.i conftest2.i conftest.out
+rm -f conftest.i conftest2.i conftest.out ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_lt_DD" >&5
-$as_echo "$ac_cv_path_lt_DD" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_path_lt_DD" >&5
+printf "%s\n" "$ac_cv_path_lt_DD" >&6; }
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking how to truncate binary pipes" >&5
-$as_echo_n "checking how to truncate binary pipes... " >&6; }
-if ${lt_cv_truncate_bin+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  printf 0123456789abcdef0123456789abcdef >conftest.i
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to truncate binary pipes" >&5
+printf %s "checking how to truncate binary pipes... " >&6; }
+if test ${lt_cv_truncate_bin+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) printf 0123456789abcdef0123456789abcdef >conftest.i
 cat conftest.i conftest.i >conftest2.i
 lt_cv_truncate_bin=
 if "$ac_cv_path_lt_DD" bs=32 count=1 <conftest2.i >conftest.out 2>/dev/null; then
@@ -6763,10 +7725,11 @@
   && lt_cv_truncate_bin="$ac_cv_path_lt_DD bs=4096 count=1"
 fi
 rm -f conftest.i conftest2.i conftest.out
-test -z "$lt_cv_truncate_bin" && lt_cv_truncate_bin="$SED -e 4q"
+test -z "$lt_cv_truncate_bin" && lt_cv_truncate_bin="$SED -e 4q" ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_truncate_bin" >&5
-$as_echo "$lt_cv_truncate_bin" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_truncate_bin" >&5
+printf "%s\n" "$lt_cv_truncate_bin" >&6; }
 
 
 
@@ -6789,7 +7752,8 @@
 }
 
 # Check whether --enable-libtool-lock was given.
-if test "${enable_libtool_lock+set}" = set; then :
+if test ${enable_libtool_lock+y}
+then :
   enableval=$enable_libtool_lock;
 fi
 
@@ -6805,9 +7769,9 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *ELF-32*)
 	HPUX_IA64_MODE=32
 	;;
@@ -6825,10 +7789,10 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     if test yes = "$lt_cv_prog_gnu_ld"; then
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -melf32bsmip"
 	  ;;
@@ -6840,7 +7804,7 @@
 	;;
       esac
     else
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -32"
 	  ;;
@@ -6863,10 +7827,10 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
     emul=elf
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *32-bit*)
 	emul="${emul}32"
 	;;
@@ -6874,7 +7838,7 @@
 	emul="${emul}64"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *MSB*)
 	emul="${emul}btsmip"
 	;;
@@ -6882,7 +7846,7 @@
 	emul="${emul}ltsmip"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *N32*)
 	emul="${emul}n32"
 	;;
@@ -6904,16 +7868,16 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
       *32-bit*)
 	case $host in
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
 	  x86_64-*linux*)
-	    case `/usr/bin/file conftest.o` in
+	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
 		;;
@@ -6967,12 +7931,13 @@
   # On SCO OpenServer 5, we need -belf to get full-featured binaries.
   SAVE_CFLAGS=$CFLAGS
   CFLAGS="$CFLAGS -belf"
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the C compiler needs -belf" >&5
-$as_echo_n "checking whether the C compiler needs -belf... " >&6; }
-if ${lt_cv_cc_needs_belf+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_ext=c
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the C compiler needs -belf" >&5
+printf %s "checking whether the C compiler needs -belf... " >&6; }
+if test ${lt_cv_cc_needs_belf+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
@@ -6982,29 +7947,32 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_cc_needs_belf=yes
-else
-  lt_cv_cc_needs_belf=no
+else case e in #(
+  e) lt_cv_cc_needs_belf=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
      ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
 ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
 ac_compiler_gnu=$ac_cv_c_compiler_gnu
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_cc_needs_belf" >&5
-$as_echo "$lt_cv_cc_needs_belf" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_cc_needs_belf" >&5
+printf "%s\n" "$lt_cv_cc_needs_belf" >&6; }
   if test yes != "$lt_cv_cc_needs_belf"; then
     # this is probably gcc 2.8.0, egcs 1.0 or newer; no need for -belf
     CFLAGS=$SAVE_CFLAGS
@@ -7017,9 +7985,9 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
     *64-bit*)
       case $lt_cv_prog_gnu_ld in
       yes*)
@@ -7054,38 +8022,44 @@
 if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}mt", so it can be a program name with args.
 set dummy ${ac_tool_prefix}mt; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_MANIFEST_TOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$MANIFEST_TOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_MANIFEST_TOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$MANIFEST_TOOL"; then
   ac_cv_prog_MANIFEST_TOOL="$MANIFEST_TOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_MANIFEST_TOOL="${ac_tool_prefix}mt"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 MANIFEST_TOOL=$ac_cv_prog_MANIFEST_TOOL
 if test -n "$MANIFEST_TOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MANIFEST_TOOL" >&5
-$as_echo "$MANIFEST_TOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MANIFEST_TOOL" >&5
+printf "%s\n" "$MANIFEST_TOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7094,38 +8068,44 @@
   ac_ct_MANIFEST_TOOL=$MANIFEST_TOOL
   # Extract the first word of "mt", so it can be a program name with args.
 set dummy mt; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_MANIFEST_TOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_MANIFEST_TOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_MANIFEST_TOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_MANIFEST_TOOL"; then
   ac_cv_prog_ac_ct_MANIFEST_TOOL="$ac_ct_MANIFEST_TOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_MANIFEST_TOOL="mt"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_MANIFEST_TOOL=$ac_cv_prog_ac_ct_MANIFEST_TOOL
 if test -n "$ac_ct_MANIFEST_TOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_MANIFEST_TOOL" >&5
-$as_echo "$ac_ct_MANIFEST_TOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_MANIFEST_TOOL" >&5
+printf "%s\n" "$ac_ct_MANIFEST_TOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_MANIFEST_TOOL" = x; then
@@ -7133,8 +8113,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     MANIFEST_TOOL=$ac_ct_MANIFEST_TOOL
@@ -7144,22 +8124,24 @@
 fi
 
 test -z "$MANIFEST_TOOL" && MANIFEST_TOOL=mt
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $MANIFEST_TOOL is a manifest tool" >&5
-$as_echo_n "checking if $MANIFEST_TOOL is a manifest tool... " >&6; }
-if ${lt_cv_path_mainfest_tool+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_path_mainfest_tool=no
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $MANIFEST_TOOL is a manifest tool" >&5
+printf %s "checking if $MANIFEST_TOOL is a manifest tool... " >&6; }
+if test ${lt_cv_path_mainfest_tool+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_path_mainfest_tool=no
   echo "$as_me:$LINENO: $MANIFEST_TOOL '-?'" >&5
   $MANIFEST_TOOL '-?' 2>conftest.err > conftest.out
   cat conftest.err >&5
   if $GREP 'Manifest Tool' conftest.out > /dev/null; then
     lt_cv_path_mainfest_tool=yes
   fi
-  rm -f conftest*
+  rm -f conftest* ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_mainfest_tool" >&5
-$as_echo "$lt_cv_path_mainfest_tool" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_path_mainfest_tool" >&5
+printf "%s\n" "$lt_cv_path_mainfest_tool" >&6; }
 if test yes != "$lt_cv_path_mainfest_tool"; then
   MANIFEST_TOOL=:
 fi
@@ -7174,38 +8156,44 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dsymutil", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dsymutil; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DSYMUTIL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$DSYMUTIL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DSYMUTIL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$DSYMUTIL"; then
   ac_cv_prog_DSYMUTIL="$DSYMUTIL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DSYMUTIL="${ac_tool_prefix}dsymutil"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 DSYMUTIL=$ac_cv_prog_DSYMUTIL
 if test -n "$DSYMUTIL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DSYMUTIL" >&5
-$as_echo "$DSYMUTIL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DSYMUTIL" >&5
+printf "%s\n" "$DSYMUTIL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7214,38 +8202,44 @@
   ac_ct_DSYMUTIL=$DSYMUTIL
   # Extract the first word of "dsymutil", so it can be a program name with args.
 set dummy dsymutil; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DSYMUTIL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_DSYMUTIL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DSYMUTIL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_DSYMUTIL"; then
   ac_cv_prog_ac_ct_DSYMUTIL="$ac_ct_DSYMUTIL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DSYMUTIL="dsymutil"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_DSYMUTIL=$ac_cv_prog_ac_ct_DSYMUTIL
 if test -n "$ac_ct_DSYMUTIL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DSYMUTIL" >&5
-$as_echo "$ac_ct_DSYMUTIL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DSYMUTIL" >&5
+printf "%s\n" "$ac_ct_DSYMUTIL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DSYMUTIL" = x; then
@@ -7253,8 +8247,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DSYMUTIL=$ac_ct_DSYMUTIL
@@ -7266,38 +8260,44 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}nmedit", so it can be a program name with args.
 set dummy ${ac_tool_prefix}nmedit; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_NMEDIT+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$NMEDIT"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_NMEDIT+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$NMEDIT"; then
   ac_cv_prog_NMEDIT="$NMEDIT" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_NMEDIT="${ac_tool_prefix}nmedit"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 NMEDIT=$ac_cv_prog_NMEDIT
 if test -n "$NMEDIT"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $NMEDIT" >&5
-$as_echo "$NMEDIT" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $NMEDIT" >&5
+printf "%s\n" "$NMEDIT" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7306,38 +8306,44 @@
   ac_ct_NMEDIT=$NMEDIT
   # Extract the first word of "nmedit", so it can be a program name with args.
 set dummy nmedit; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_NMEDIT+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_NMEDIT"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_NMEDIT+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_NMEDIT"; then
   ac_cv_prog_ac_ct_NMEDIT="$ac_ct_NMEDIT" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_NMEDIT="nmedit"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_NMEDIT=$ac_cv_prog_ac_ct_NMEDIT
 if test -n "$ac_ct_NMEDIT"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_NMEDIT" >&5
-$as_echo "$ac_ct_NMEDIT" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_NMEDIT" >&5
+printf "%s\n" "$ac_ct_NMEDIT" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_NMEDIT" = x; then
@@ -7345,8 +8351,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     NMEDIT=$ac_ct_NMEDIT
@@ -7358,38 +8364,44 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}lipo", so it can be a program name with args.
 set dummy ${ac_tool_prefix}lipo; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_LIPO+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$LIPO"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_LIPO+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$LIPO"; then
   ac_cv_prog_LIPO="$LIPO" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_LIPO="${ac_tool_prefix}lipo"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 LIPO=$ac_cv_prog_LIPO
 if test -n "$LIPO"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $LIPO" >&5
-$as_echo "$LIPO" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $LIPO" >&5
+printf "%s\n" "$LIPO" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7398,38 +8410,44 @@
   ac_ct_LIPO=$LIPO
   # Extract the first word of "lipo", so it can be a program name with args.
 set dummy lipo; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_LIPO+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_LIPO"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_LIPO+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_LIPO"; then
   ac_cv_prog_ac_ct_LIPO="$ac_ct_LIPO" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_LIPO="lipo"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_LIPO=$ac_cv_prog_ac_ct_LIPO
 if test -n "$ac_ct_LIPO"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_LIPO" >&5
-$as_echo "$ac_ct_LIPO" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_LIPO" >&5
+printf "%s\n" "$ac_ct_LIPO" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_LIPO" = x; then
@@ -7437,8 +8455,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     LIPO=$ac_ct_LIPO
@@ -7450,38 +8468,44 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}otool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}otool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$OTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$OTOOL"; then
   ac_cv_prog_OTOOL="$OTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OTOOL="${ac_tool_prefix}otool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 OTOOL=$ac_cv_prog_OTOOL
 if test -n "$OTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OTOOL" >&5
-$as_echo "$OTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OTOOL" >&5
+printf "%s\n" "$OTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7490,38 +8514,44 @@
   ac_ct_OTOOL=$OTOOL
   # Extract the first word of "otool", so it can be a program name with args.
 set dummy otool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_OTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_OTOOL"; then
   ac_cv_prog_ac_ct_OTOOL="$ac_ct_OTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OTOOL="otool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_OTOOL=$ac_cv_prog_ac_ct_OTOOL
 if test -n "$ac_ct_OTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL" >&5
-$as_echo "$ac_ct_OTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL" >&5
+printf "%s\n" "$ac_ct_OTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OTOOL" = x; then
@@ -7529,8 +8559,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OTOOL=$ac_ct_OTOOL
@@ -7542,38 +8572,44 @@
     if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}otool64", so it can be a program name with args.
 set dummy ${ac_tool_prefix}otool64; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OTOOL64+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$OTOOL64"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OTOOL64+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$OTOOL64"; then
   ac_cv_prog_OTOOL64="$OTOOL64" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OTOOL64="${ac_tool_prefix}otool64"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 OTOOL64=$ac_cv_prog_OTOOL64
 if test -n "$OTOOL64"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OTOOL64" >&5
-$as_echo "$OTOOL64" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OTOOL64" >&5
+printf "%s\n" "$OTOOL64" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -7582,38 +8618,44 @@
   ac_ct_OTOOL64=$OTOOL64
   # Extract the first word of "otool64", so it can be a program name with args.
 set dummy otool64; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OTOOL64+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_OTOOL64"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OTOOL64+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_OTOOL64"; then
   ac_cv_prog_ac_ct_OTOOL64="$ac_ct_OTOOL64" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OTOOL64="otool64"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_OTOOL64=$ac_cv_prog_ac_ct_OTOOL64
 if test -n "$ac_ct_OTOOL64"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL64" >&5
-$as_echo "$ac_ct_OTOOL64" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OTOOL64" >&5
+printf "%s\n" "$ac_ct_OTOOL64" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OTOOL64" = x; then
@@ -7621,8 +8663,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OTOOL64=$ac_ct_OTOOL64
@@ -7657,12 +8699,13 @@
 
 
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -single_module linker flag" >&5
-$as_echo_n "checking for -single_module linker flag... " >&6; }
-if ${lt_cv_apple_cc_single_mod+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_apple_cc_single_mod=no
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -single_module linker flag" >&5
+printf %s "checking for -single_module linker flag... " >&6; }
+if test ${lt_cv_apple_cc_single_mod+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_apple_cc_single_mod=no
       if test -z "$LT_MULTI_MODULE"; then
 	# By default we will add the -single_module flag. You can override
 	# by either setting the environment variable LT_MULTI_MODULE
@@ -7688,17 +8731,19 @@
 	fi
 	rm -rf libconftest.dylib*
 	rm -f conftest.*
-      fi
+      fi ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_apple_cc_single_mod" >&5
-$as_echo "$lt_cv_apple_cc_single_mod" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_apple_cc_single_mod" >&5
+printf "%s\n" "$lt_cv_apple_cc_single_mod" >&6; }
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -exported_symbols_list linker flag" >&5
-$as_echo_n "checking for -exported_symbols_list linker flag... " >&6; }
-if ${lt_cv_ld_exported_symbols_list+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_ld_exported_symbols_list=no
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -exported_symbols_list linker flag" >&5
+printf %s "checking for -exported_symbols_list linker flag... " >&6; }
+if test ${lt_cv_ld_exported_symbols_list+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_ld_exported_symbols_list=no
       save_LDFLAGS=$LDFLAGS
       echo "_main" > conftest.sym
       LDFLAGS="$LDFLAGS -Wl,-exported_symbols_list,conftest.sym"
@@ -7706,39 +8751,43 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_ld_exported_symbols_list=yes
-else
-  lt_cv_ld_exported_symbols_list=no
+else case e in #(
+  e) lt_cv_ld_exported_symbols_list=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
 	LDFLAGS=$save_LDFLAGS
-
+     ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_exported_symbols_list" >&5
-$as_echo "$lt_cv_ld_exported_symbols_list" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_exported_symbols_list" >&5
+printf "%s\n" "$lt_cv_ld_exported_symbols_list" >&6; }
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -force_load linker flag" >&5
-$as_echo_n "checking for -force_load linker flag... " >&6; }
-if ${lt_cv_ld_force_load+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_ld_force_load=no
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for -force_load linker flag" >&5
+printf %s "checking for -force_load linker flag... " >&6; }
+if test ${lt_cv_ld_force_load+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_ld_force_load=no
       cat > conftest.c << _LT_EOF
 int forced_loaded() { return 2;}
 _LT_EOF
       echo "$LTCC $LTCFLAGS -c -o conftest.o conftest.c" >&5
       $LTCC $LTCFLAGS -c -o conftest.o conftest.c 2>&5
-      echo "$AR cru libconftest.a conftest.o" >&5
-      $AR cru libconftest.a conftest.o 2>&5
+      echo "$AR $AR_FLAGS libconftest.a conftest.o" >&5
+      $AR $AR_FLAGS libconftest.a conftest.o 2>&5
       echo "$RANLIB libconftest.a" >&5
       $RANLIB libconftest.a 2>&5
       cat > conftest.c << _LT_EOF
@@ -7756,26 +8805,22 @@
       fi
         rm -f conftest.err libconftest.a conftest conftest.c
         rm -rf conftest.dSYM
-
+     ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_force_load" >&5
-$as_echo "$lt_cv_ld_force_load" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_ld_force_load" >&5
+printf "%s\n" "$lt_cv_ld_force_load" >&6; }
     case $host_os in
     rhapsody* | darwin1.[012])
       _lt_dar_allow_undefined='$wl-undefined ${wl}suppress' ;;
     darwin1.*)
       _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-    darwin*) # darwin 5.x on
-      # if running on 10.5 or later, the deployment target defaults
-      # to the OS version, if on x86, and 10.4, the deployment
-      # target defaults to 10.4. Don't you love it?
-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
-	10.0,*86*-darwin8*|10.0,*-darwin[91]*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
-	10.[012][,.]*)
-	  _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-	10.*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+    darwin*)
+      case $MACOSX_DEPLOYMENT_TARGET,$host in
+        10.[012],*|,*powerpc*-darwin[5-8]*)
+          _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+        *)
+          _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
       esac
     ;;
   esac
@@ -7830,148 +8875,42 @@
     esac
 }
 
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
-$as_echo_n "checking for ANSI C header files... " >&6; }
-if ${ac_cv_header_stdc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-int
-main ()
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_header_stdc=yes
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "memchr" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "free" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then :
-  :
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <ctype.h>
-#include <stdlib.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) \
-		   (('a' <= (c) && (c) <= 'i') \
-		     || ('j' <= (c) && (c) <= 'r') \
-		     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-	|| toupper (i) != TOUPPER (i))
-      return 2;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
-$as_echo "$ac_cv_header_stdc" >&6; }
-if test $ac_cv_header_stdc = yes; then
-
-$as_echo "#define STDC_HEADERS 1" >>confdefs.h
-
-fi
-
-# On IRIX 5.3, sys/types and inttypes.h are conflicting.
-for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
-		  inttypes.h stdint.h unistd.h
-do :
-  as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
-ac_fn_c_check_header_compile "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default
-"
-if eval test \"x\$"$as_ac_Header"\" = x"yes"; then :
-  cat >>confdefs.h <<_ACEOF
-#define `$as_echo "HAVE_$ac_header" | $as_tr_cpp` 1
-_ACEOF
-
-fi
-
+ac_header= ac_cache=
+for ac_item in $ac_header_c_list
+do
+  if test $ac_cache; then
+    ac_fn_c_check_header_compile "$LINENO" $ac_header ac_cv_header_$ac_cache "$ac_includes_default"
+    if eval test \"x\$ac_cv_header_$ac_cache\" = xyes; then
+      printf "%s\n" "#define $ac_item 1" >> confdefs.h
+    fi
+    ac_header= ac_cache=
+  elif test $ac_header; then
+    ac_cache=$ac_item
+  else
+    ac_header=$ac_item
+  fi
 done
 
 
-for ac_header in dlfcn.h
-do :
-  ac_fn_c_check_header_compile "$LINENO" "dlfcn.h" "ac_cv_header_dlfcn_h" "$ac_includes_default
-"
-if test "x$ac_cv_header_dlfcn_h" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_DLFCN_H 1
-_ACEOF
+
+
+
+
+
+
+if test $ac_cv_header_stdlib_h = yes && test $ac_cv_header_string_h = yes
+then :
+
+printf "%s\n" "#define STDC_HEADERS 1" >>confdefs.h
 
 fi
+ac_fn_c_check_header_compile "$LINENO" "dlfcn.h" "ac_cv_header_dlfcn_h" "$ac_includes_default
+"
+if test "x$ac_cv_header_dlfcn_h" = xyes
+then :
+  printf "%s\n" "#define HAVE_DLFCN_H 1" >>confdefs.h
 
-done
+fi
 
 
 
@@ -7985,38 +8924,44 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}as", so it can be a program name with args.
 set dummy ${ac_tool_prefix}as; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_AS+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$AS"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_AS+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$AS"; then
   ac_cv_prog_AS="$AS" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_AS="${ac_tool_prefix}as"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 AS=$ac_cv_prog_AS
 if test -n "$AS"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $AS" >&5
-$as_echo "$AS" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $AS" >&5
+printf "%s\n" "$AS" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8025,38 +8970,44 @@
   ac_ct_AS=$AS
   # Extract the first word of "as", so it can be a program name with args.
 set dummy as; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_AS+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_AS"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_AS+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_AS"; then
   ac_cv_prog_ac_ct_AS="$ac_ct_AS" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_AS="as"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_AS=$ac_cv_prog_ac_ct_AS
 if test -n "$ac_ct_AS"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AS" >&5
-$as_echo "$ac_ct_AS" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_AS" >&5
+printf "%s\n" "$ac_ct_AS" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_AS" = x; then
@@ -8064,8 +9015,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     AS=$ac_ct_AS
@@ -8077,38 +9028,44 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}dlltool", so it can be a program name with args.
 set dummy ${ac_tool_prefix}dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$DLLTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$DLLTOOL"; then
   ac_cv_prog_DLLTOOL="$DLLTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_DLLTOOL="${ac_tool_prefix}dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 DLLTOOL=$ac_cv_prog_DLLTOOL
 if test -n "$DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
-$as_echo "$DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $DLLTOOL" >&5
+printf "%s\n" "$DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8117,38 +9074,44 @@
   ac_ct_DLLTOOL=$DLLTOOL
   # Extract the first word of "dlltool", so it can be a program name with args.
 set dummy dlltool; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_DLLTOOL+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_DLLTOOL"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_DLLTOOL+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_DLLTOOL"; then
   ac_cv_prog_ac_ct_DLLTOOL="$ac_ct_DLLTOOL" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_DLLTOOL="dlltool"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_DLLTOOL=$ac_cv_prog_ac_ct_DLLTOOL
 if test -n "$ac_ct_DLLTOOL"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
-$as_echo "$ac_ct_DLLTOOL" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_DLLTOOL" >&5
+printf "%s\n" "$ac_ct_DLLTOOL" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_DLLTOOL" = x; then
@@ -8156,8 +9119,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     DLLTOOL=$ac_ct_DLLTOOL
@@ -8169,38 +9132,44 @@
   if test -n "$ac_tool_prefix"; then
   # Extract the first word of "${ac_tool_prefix}objdump", so it can be a program name with args.
 set dummy ${ac_tool_prefix}objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$OBJDUMP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$OBJDUMP"; then
   ac_cv_prog_OBJDUMP="$OBJDUMP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_OBJDUMP="${ac_tool_prefix}objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 OBJDUMP=$ac_cv_prog_OBJDUMP
 if test -n "$OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
-$as_echo "$OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $OBJDUMP" >&5
+printf "%s\n" "$OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8209,38 +9178,44 @@
   ac_ct_OBJDUMP=$OBJDUMP
   # Extract the first word of "objdump", so it can be a program name with args.
 set dummy objdump; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_ac_ct_OBJDUMP+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$ac_ct_OBJDUMP"; then
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+printf %s "checking for $ac_word... " >&6; }
+if test ${ac_cv_prog_ac_ct_OBJDUMP+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) if test -n "$ac_ct_OBJDUMP"; then
   ac_cv_prog_ac_ct_OBJDUMP="$ac_ct_OBJDUMP" # Let the user override the test.
 else
 as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
     for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
+  if as_fn_executable_p "$as_dir$ac_word$ac_exec_ext"; then
     ac_cv_prog_ac_ct_OBJDUMP="objdump"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: found $as_dir$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-fi
+fi ;;
+esac
 fi
 ac_ct_OBJDUMP=$ac_cv_prog_ac_ct_OBJDUMP
 if test -n "$ac_ct_OBJDUMP"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
-$as_echo "$ac_ct_OBJDUMP" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_ct_OBJDUMP" >&5
+printf "%s\n" "$ac_ct_OBJDUMP" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
   if test "x$ac_ct_OBJDUMP" = x; then
@@ -8248,8 +9223,8 @@
   else
     case $cross_compiling:$ac_tool_warned in
 yes:)
-{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
-$as_echo "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: using cross tools not prefixed with host triplet" >&5
+printf "%s\n" "$as_me: WARNING: using cross tools not prefixed with host triplet" >&2;}
 ac_tool_warned=yes ;;
 esac
     OBJDUMP=$ac_ct_OBJDUMP
@@ -8286,7 +9261,8 @@
 
 
             # Check whether --enable-shared was given.
-if test "${enable_shared+set}" = set; then :
+if test ${enable_shared+y}
+then :
   enableval=$enable_shared; p=${PACKAGE-default}
     case $enableval in
     yes) enable_shared=yes ;;
@@ -8304,8 +9280,9 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
-  enable_shared=yes
+else case e in #(
+  e) enable_shared=yes ;;
+esac
 fi
 
 
@@ -8317,7 +9294,8 @@
 
 
   # Check whether --enable-static was given.
-if test "${enable_static+set}" = set; then :
+if test ${enable_static+y}
+then :
   enableval=$enable_static; p=${PACKAGE-default}
     case $enableval in
     yes) enable_static=yes ;;
@@ -8335,8 +9313,9 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
-  enable_static=yes
+else case e in #(
+  e) enable_static=yes ;;
+esac
 fi
 
 
@@ -8349,7 +9328,8 @@
 
 
 # Check whether --with-pic was given.
-if test "${with_pic+set}" = set; then :
+if test ${with_pic+y}
+then :
   withval=$with_pic; lt_p=${PACKAGE-default}
     case $withval in
     yes|no) pic_mode=$withval ;;
@@ -8366,8 +9346,9 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
-  pic_mode=default
+else case e in #(
+  e) pic_mode=default ;;
+esac
 fi
 
 
@@ -8378,7 +9359,8 @@
 
 
   # Check whether --enable-fast-install was given.
-if test "${enable_fast_install+set}" = set; then :
+if test ${enable_fast_install+y}
+then :
   enableval=$enable_fast_install; p=${PACKAGE-default}
     case $enableval in
     yes) enable_fast_install=yes ;;
@@ -8396,8 +9378,9 @@
       IFS=$lt_save_ifs
       ;;
     esac
-else
-  enable_fast_install=yes
+else case e in #(
+  e) enable_fast_install=yes ;;
+esac
 fi
 
 
@@ -8410,11 +9393,12 @@
   shared_archive_member_spec=
 case $host,$enable_shared in
 power*-*-aix[5-9]*,yes)
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking which variant of shared library versioning to provide" >&5
-$as_echo_n "checking which variant of shared library versioning to provide... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking which variant of shared library versioning to provide" >&5
+printf %s "checking which variant of shared library versioning to provide... " >&6; }
 
 # Check whether --with-aix-soname was given.
-if test "${with_aix_soname+set}" = set; then :
+if test ${with_aix_soname+y}
+then :
   withval=$with_aix_soname; case $withval in
     aix|svr4|both)
       ;;
@@ -8423,18 +9407,21 @@
       ;;
     esac
     lt_cv_with_aix_soname=$with_aix_soname
-else
-  if ${lt_cv_with_aix_soname+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_with_aix_soname=aix
+else case e in #(
+  e) if test ${lt_cv_with_aix_soname+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_with_aix_soname=aix ;;
+esac
 fi
 
-    with_aix_soname=$lt_cv_with_aix_soname
+    with_aix_soname=$lt_cv_with_aix_soname ;;
+esac
 fi
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_aix_soname" >&5
-$as_echo "$with_aix_soname" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $with_aix_soname" >&5
+printf "%s\n" "$with_aix_soname" >&6; }
   if test aix != "$with_aix_soname"; then
     # For the AIX way of multilib, we name the shared archive member
     # based on the bitwidth used, traditionally 'shr.o' or 'shr_64.o',
@@ -8516,12 +9503,13 @@
    setopt NO_GLOB_SUBST
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for objdir" >&5
-$as_echo_n "checking for objdir... " >&6; }
-if ${lt_cv_objdir+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  rm -f .libs 2>/dev/null
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for objdir" >&5
+printf %s "checking for objdir... " >&6; }
+if test ${lt_cv_objdir+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) rm -f .libs 2>/dev/null
 mkdir .libs 2>/dev/null
 if test -d .libs; then
   lt_cv_objdir=.libs
@@ -8529,19 +9517,18 @@
   # MS-DOS does not allow filenames that begin with a dot.
   lt_cv_objdir=_libs
 fi
-rmdir .libs 2>/dev/null
+rmdir .libs 2>/dev/null ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_objdir" >&5
-$as_echo "$lt_cv_objdir" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_objdir" >&5
+printf "%s\n" "$lt_cv_objdir" >&6; }
 objdir=$lt_cv_objdir
 
 
 
 
 
-cat >>confdefs.h <<_ACEOF
-#define LT_OBJDIR "$lt_cv_objdir/"
-_ACEOF
+printf "%s\n" "#define LT_OBJDIR \"$lt_cv_objdir/\"" >>confdefs.h
 
 
 
@@ -8562,8 +9549,8 @@
 ofile=libtool
 can_build_shared=yes
 
-# All known linkers require a '.a' archive for static linking (except MSVC,
-# which needs '.lib').
+# All known linkers require a '.a' archive for static linking (except MSVC and
+# ICC, which need '.lib').
 libext=a
 
 with_gnu_ld=$lt_cv_prog_gnu_ld
@@ -8587,12 +9574,13 @@
 case $deplibs_check_method in
 file_magic*)
   if test "$file_magic_cmd" = '$MAGIC_CMD'; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${ac_tool_prefix}file" >&5
-$as_echo_n "checking for ${ac_tool_prefix}file... " >&6; }
-if ${lt_cv_path_MAGIC_CMD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  case $MAGIC_CMD in
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ${ac_tool_prefix}file" >&5
+printf %s "checking for ${ac_tool_prefix}file... " >&6; }
+if test ${lt_cv_path_MAGIC_CMD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) case $MAGIC_CMD in
 [\\/*] |  ?:[\\/]*)
   lt_cv_path_MAGIC_CMD=$MAGIC_CMD # Let the user override the test with a path.
   ;;
@@ -8635,16 +9623,17 @@
   IFS=$lt_save_ifs
   MAGIC_CMD=$lt_save_MAGIC_CMD
   ;;
+esac ;;
 esac
 fi
 
 MAGIC_CMD=$lt_cv_path_MAGIC_CMD
 if test -n "$MAGIC_CMD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
-$as_echo "$MAGIC_CMD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
+printf "%s\n" "$MAGIC_CMD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8653,12 +9642,13 @@
 
 if test -z "$lt_cv_path_MAGIC_CMD"; then
   if test -n "$ac_tool_prefix"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for file" >&5
-$as_echo_n "checking for file... " >&6; }
-if ${lt_cv_path_MAGIC_CMD+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  case $MAGIC_CMD in
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for file" >&5
+printf %s "checking for file... " >&6; }
+if test ${lt_cv_path_MAGIC_CMD+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) case $MAGIC_CMD in
 [\\/*] |  ?:[\\/]*)
   lt_cv_path_MAGIC_CMD=$MAGIC_CMD # Let the user override the test with a path.
   ;;
@@ -8701,16 +9691,17 @@
   IFS=$lt_save_ifs
   MAGIC_CMD=$lt_save_MAGIC_CMD
   ;;
+esac ;;
 esac
 fi
 
 MAGIC_CMD=$lt_cv_path_MAGIC_CMD
 if test -n "$MAGIC_CMD"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
-$as_echo "$MAGIC_CMD" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $MAGIC_CMD" >&5
+printf "%s\n" "$MAGIC_CMD" >&6; }
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
 
 
@@ -8795,12 +9786,13 @@
     lt_prog_compiler_no_builtin_flag=' -fno-builtin' ;;
   esac
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -fno-rtti -fno-exceptions" >&5
-$as_echo_n "checking if $compiler supports -fno-rtti -fno-exceptions... " >&6; }
-if ${lt_cv_prog_compiler_rtti_exceptions+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_rtti_exceptions=no
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -fno-rtti -fno-exceptions" >&5
+printf %s "checking if $compiler supports -fno-rtti -fno-exceptions... " >&6; }
+if test ${lt_cv_prog_compiler_rtti_exceptions+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_rtti_exceptions=no
    ac_outfile=conftest.$ac_objext
    echo "$lt_simple_compile_test_code" > conftest.$ac_ext
    lt_compiler_flag="-fno-rtti -fno-exceptions"  ## exclude from sc_useless_quotes_in_assignment
@@ -8828,10 +9820,11 @@
      fi
    fi
    $RM conftest*
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_rtti_exceptions" >&5
-$as_echo "$lt_cv_prog_compiler_rtti_exceptions" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_rtti_exceptions" >&5
+printf "%s\n" "$lt_cv_prog_compiler_rtti_exceptions" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_rtti_exceptions"; then
     lt_prog_compiler_no_builtin_flag="$lt_prog_compiler_no_builtin_flag -fno-rtti -fno-exceptions"
@@ -9072,7 +10065,7 @@
 	lt_prog_compiler_static='-qstaticlink'
 	;;
       *)
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ Ceres\ Fortran* | *Sun*Fortran*\ [1-7].* | *Sun*Fortran*\ 8.[0-3]*)
 	  # Sun Fortran 8.3 passes all unrecognized flags to the linker
 	  lt_prog_compiler_pic='-KPIC'
@@ -9188,27 +10181,30 @@
     ;;
 esac
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $compiler option to produce PIC" >&5
-$as_echo_n "checking for $compiler option to produce PIC... " >&6; }
-if ${lt_cv_prog_compiler_pic+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_pic=$lt_prog_compiler_pic
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for $compiler option to produce PIC" >&5
+printf %s "checking for $compiler option to produce PIC... " >&6; }
+if test ${lt_cv_prog_compiler_pic+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_pic=$lt_prog_compiler_pic ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic" >&5
-$as_echo "$lt_cv_prog_compiler_pic" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic" >&5
+printf "%s\n" "$lt_cv_prog_compiler_pic" >&6; }
 lt_prog_compiler_pic=$lt_cv_prog_compiler_pic
 
 #
 # Check to make sure the PIC flag actually works.
 #
 if test -n "$lt_prog_compiler_pic"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler PIC flag $lt_prog_compiler_pic works" >&5
-$as_echo_n "checking if $compiler PIC flag $lt_prog_compiler_pic works... " >&6; }
-if ${lt_cv_prog_compiler_pic_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_pic_works=no
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler PIC flag $lt_prog_compiler_pic works" >&5
+printf %s "checking if $compiler PIC flag $lt_prog_compiler_pic works... " >&6; }
+if test ${lt_cv_prog_compiler_pic_works+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_pic_works=no
    ac_outfile=conftest.$ac_objext
    echo "$lt_simple_compile_test_code" > conftest.$ac_ext
    lt_compiler_flag="$lt_prog_compiler_pic -DPIC"  ## exclude from sc_useless_quotes_in_assignment
@@ -9236,10 +10232,11 @@
      fi
    fi
    $RM conftest*
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic_works" >&5
-$as_echo "$lt_cv_prog_compiler_pic_works" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_pic_works" >&5
+printf "%s\n" "$lt_cv_prog_compiler_pic_works" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_pic_works"; then
     case $lt_prog_compiler_pic in
@@ -9267,12 +10264,13 @@
 # Check to make sure the static flag actually works.
 #
 wl=$lt_prog_compiler_wl eval lt_tmp_static_flag=\"$lt_prog_compiler_static\"
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler static flag $lt_tmp_static_flag works" >&5
-$as_echo_n "checking if $compiler static flag $lt_tmp_static_flag works... " >&6; }
-if ${lt_cv_prog_compiler_static_works+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_static_works=no
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler static flag $lt_tmp_static_flag works" >&5
+printf %s "checking if $compiler static flag $lt_tmp_static_flag works... " >&6; }
+if test ${lt_cv_prog_compiler_static_works+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_static_works=no
    save_LDFLAGS=$LDFLAGS
    LDFLAGS="$LDFLAGS $lt_tmp_static_flag"
    echo "$lt_simple_link_test_code" > conftest.$ac_ext
@@ -9293,10 +10291,11 @@
    fi
    $RM -r conftest*
    LDFLAGS=$save_LDFLAGS
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_static_works" >&5
-$as_echo "$lt_cv_prog_compiler_static_works" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_static_works" >&5
+printf "%s\n" "$lt_cv_prog_compiler_static_works" >&6; }
 
 if test yes = "$lt_cv_prog_compiler_static_works"; then
     :
@@ -9310,12 +10309,13 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
-$as_echo_n "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
-if ${lt_cv_prog_compiler_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_c_o=no
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
+printf %s "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
+if test ${lt_cv_prog_compiler_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_c_o=no
    $RM -r conftest 2>/dev/null
    mkdir conftest
    cd conftest
@@ -9355,22 +10355,24 @@
    cd ..
    $RM -r conftest
    $RM conftest*
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
-$as_echo "$lt_cv_prog_compiler_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
+printf "%s\n" "$lt_cv_prog_compiler_c_o" >&6; }
 
 
 
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
-$as_echo_n "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
-if ${lt_cv_prog_compiler_c_o+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler_c_o=no
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $compiler supports -c -o file.$ac_objext" >&5
+printf %s "checking if $compiler supports -c -o file.$ac_objext... " >&6; }
+if test ${lt_cv_prog_compiler_c_o+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler_c_o=no
    $RM -r conftest 2>/dev/null
    mkdir conftest
    cd conftest
@@ -9410,10 +10412,11 @@
    cd ..
    $RM -r conftest
    $RM conftest*
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
-$as_echo "$lt_cv_prog_compiler_c_o" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler_c_o" >&5
+printf "%s\n" "$lt_cv_prog_compiler_c_o" >&6; }
 
 
 
@@ -9421,19 +10424,19 @@
 hard_links=nottested
 if test no = "$lt_cv_prog_compiler_c_o" && test no != "$need_locks"; then
   # do not overwrite the value of need_locks provided by the user
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if we can lock with hard links" >&5
-$as_echo_n "checking if we can lock with hard links... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if we can lock with hard links" >&5
+printf %s "checking if we can lock with hard links... " >&6; }
   hard_links=yes
   $RM conftest*
   ln conftest.a conftest.b 2>/dev/null && hard_links=no
   touch conftest.a
   ln conftest.a conftest.b 2>&5 || hard_links=no
   ln conftest.a conftest.b 2>/dev/null && hard_links=no
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $hard_links" >&5
-$as_echo "$hard_links" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $hard_links" >&5
+printf "%s\n" "$hard_links" >&6; }
   if test no = "$hard_links"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&5
-$as_echo "$as_me: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&2;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&5
+printf "%s\n" "$as_me: WARNING: '$CC' does not support '-c -o', so 'make -j' may be unsafe" >&2;}
     need_locks=warn
   fi
 else
@@ -9445,8 +10448,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the $compiler linker ($LD) supports shared libraries" >&5
-$as_echo_n "checking whether the $compiler linker ($LD) supports shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the $compiler linker ($LD) supports shared libraries" >&5
+printf %s "checking whether the $compiler linker ($LD) supports shared libraries... " >&6; }
 
   runpath_var=
   allow_undefined_flag=
@@ -9490,15 +10493,15 @@
 
   case $host_os in
   cygwin* | mingw* | pw32* | cegcc*)
-    # FIXME: the MSVC++ port hasn't been tested in a loooong time
+    # FIXME: the MSVC++ and ICC port hasn't been tested in a loooong time
     # When not using gcc, we currently assume that we are using
-    # Microsoft Visual C++.
+    # Microsoft Visual C++ or Intel C++ Compiler.
     if test yes != "$GCC"; then
       with_gnu_ld=no
     fi
     ;;
   interix*)
-    # we just hope/assume this is gcc and not c89 (= MSVC++)
+    # we just hope/assume this is gcc and not c89 (= MSVC++ or ICC)
     with_gnu_ld=yes
     ;;
   openbsd* | bitrig*)
@@ -9550,7 +10553,7 @@
       whole_archive_flag_spec=
     fi
     supports_anon_versioning=no
-    case `$LD -v | $SED -e 's/(^)\+)\s\+//' 2>&1` in
+    case `$LD -v | $SED -e 's/([^)]\+)\s\+//' 2>&1` in
       *GNU\ gold*) supports_anon_versioning=yes ;;
       *\ [01].* | *\ 2.[0-9].* | *\ 2.10.*) ;; # catch versions < 2.11
       *\ 2.11.93.0.2\ *) supports_anon_versioning=yes ;; # RH7.3 ...
@@ -9662,6 +10665,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       old_archive_From_new_cmds='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       enable_shared_with_static_runtimes=yes
+      file_list_spec='@'
       ;;
 
     interix[3-9]*)
@@ -9676,7 +10680,7 @@
       # 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
       # time.  Moving up from 0x10000000 also allows more sbrk(2) space.
       archive_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-      archive_expsym_cmds='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+      archive_expsym_cmds='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
       ;;
 
     gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu)
@@ -9719,7 +10723,7 @@
 	  compiler_needs_object=yes
 	  ;;
 	esac
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ C*)			# Sun C 5.9
 	  whole_archive_flag_spec='$wl--whole-archive`new_convenience=; for conv in $convenience\"\"; do test -z \"$conv\" || new_convenience=\"$new_convenience,$conv\"; done; func_echo_all \"$new_convenience\"` $wl--no-whole-archive'
 	  compiler_needs_object=yes
@@ -9731,7 +10735,7 @@
 
         if test yes = "$supports_anon_versioning"; then
           archive_expsym_cmds='echo "{ global:" > $output_objdir/$libname.ver~
-            cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+            cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
             echo "local: *; };" >> $output_objdir/$libname.ver~
             $CC '"$tmp_sharedflag""$tmp_addflag"' $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
         fi
@@ -9747,7 +10751,7 @@
 	  archive_cmds='$LD -shared $libobjs $deplibs $linker_flags -soname $soname -o $lib'
 	  if test yes = "$supports_anon_versioning"; then
 	    archive_expsym_cmds='echo "{ global:" > $output_objdir/$libname.ver~
-              cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+              cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
               echo "local: *; };" >> $output_objdir/$libname.ver~
               $LD -shared $libobjs $deplibs $linker_flags -soname $soname -version-script $output_objdir/$libname.ver -o $lib'
 	  fi
@@ -9879,7 +10883,7 @@
 	if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
 	  export_symbols_cmds='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && (substr(\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
 	else
-	  export_symbols_cmds='`func_echo_all $NM | $SED -e '\''s/B\([^B]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && (substr(\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+	  export_symbols_cmds='`func_echo_all $NM | $SED -e '\''s/B\([^B]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && (substr(\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
 	fi
 	aix_use_runtimelinking=no
 
@@ -10001,21 +11005,23 @@
         if test set = "${lt_cv_aix_libpath+set}"; then
   aix_libpath=$lt_cv_aix_libpath
 else
-  if ${lt_cv_aix_libpath_+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+  if test ${lt_cv_aix_libpath_+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
 
   lt_aix_libpath_sed='
       /Import File Strings/,/^$/ {
@@ -10030,12 +11036,13 @@
     lt_cv_aix_libpath_=`dump -HX64 conftest$ac_exeext 2>/dev/null | $SED -n -e "$lt_aix_libpath_sed"`
   fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
   if test -z "$lt_cv_aix_libpath_"; then
     lt_cv_aix_libpath_=/usr/lib:/lib
   fi
-
+   ;;
+esac
 fi
 
   aix_libpath=$lt_cv_aix_libpath_
@@ -10054,21 +11061,23 @@
 	 if test set = "${lt_cv_aix_libpath+set}"; then
   aix_libpath=$lt_cv_aix_libpath
 else
-  if ${lt_cv_aix_libpath_+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+  if test ${lt_cv_aix_libpath_+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
 
   lt_aix_libpath_sed='
       /Import File Strings/,/^$/ {
@@ -10083,12 +11092,13 @@
     lt_cv_aix_libpath_=`dump -HX64 conftest$ac_exeext 2>/dev/null | $SED -n -e "$lt_aix_libpath_sed"`
   fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
   if test -z "$lt_cv_aix_libpath_"; then
     lt_cv_aix_libpath_=/usr/lib:/lib
   fi
-
+   ;;
+esac
 fi
 
   aix_libpath=$lt_cv_aix_libpath_
@@ -10146,12 +11156,12 @@
 
     cygwin* | mingw* | pw32* | cegcc*)
       # When not using gcc, we currently assume that we are using
-      # Microsoft Visual C++.
+      # Microsoft Visual C++ or Intel C++ Compiler.
       # hardcode_libdir_flag_spec is actually meaningless, as there is
       # no search path for DLLs.
       case $cc_basename in
-      cl*)
-	# Native MSVC
+      cl* | icl*)
+	# Native MSVC or ICC
 	hardcode_libdir_flag_spec=' '
 	allow_undefined_flag=unsupported
 	always_export_symbols=yes
@@ -10192,7 +11202,7 @@
           fi'
 	;;
       *)
-	# Assume MSVC wrapper
+	# Assume MSVC and ICC wrapper
 	hardcode_libdir_flag_spec=' '
 	allow_undefined_flag=unsupported
 	# Tell ltmain to make .lib files, not .a files.
@@ -10233,8 +11243,8 @@
     output_verbose_link_cmd=func_echo_all
     archive_cmds="\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dsymutil"
     module_cmds="\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dsymutil"
-    archive_expsym_cmds="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
-    module_expsym_cmds="sed -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
+    archive_expsym_cmds="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
+    module_expsym_cmds="$SED -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
 
   else
   ld_shlibs=no
@@ -10268,7 +11278,7 @@
       ;;
 
     # FreeBSD 3 and greater uses gcc -shared to do shared libraries.
-    freebsd* | dragonfly*)
+    freebsd* | dragonfly* | midnightbsd*)
       archive_cmds='$CC -shared $pic_flag -o $lib $libobjs $deplibs $compiler_flags'
       hardcode_libdir_flag_spec='-R$libdir'
       hardcode_direct=yes
@@ -10334,12 +11344,13 @@
 
 	  # Older versions of the 11.00 compiler do not understand -b yet
 	  # (HP92453-01 A.11.01.20 doesn't, HP92453-01 B.11.X.35175-35176.GP does)
-	  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if $CC understands -b" >&5
-$as_echo_n "checking if $CC understands -b... " >&6; }
-if ${lt_cv_prog_compiler__b+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_prog_compiler__b=no
+	  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $CC understands -b" >&5
+printf %s "checking if $CC understands -b... " >&6; }
+if test ${lt_cv_prog_compiler__b+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_prog_compiler__b=no
    save_LDFLAGS=$LDFLAGS
    LDFLAGS="$LDFLAGS -b"
    echo "$lt_simple_link_test_code" > conftest.$ac_ext
@@ -10360,10 +11371,11 @@
    fi
    $RM -r conftest*
    LDFLAGS=$save_LDFLAGS
-
+ ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler__b" >&5
-$as_echo "$lt_cv_prog_compiler__b" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_prog_compiler__b" >&5
+printf "%s\n" "$lt_cv_prog_compiler__b" >&6; }
 
 if test yes = "$lt_cv_prog_compiler__b"; then
     archive_cmds='$CC -b $wl+h $wl$soname $wl+b $wl$install_libdir -o $lib $libobjs $deplibs $compiler_flags'
@@ -10403,28 +11415,32 @@
 	# work, assume that -exports_file does not work either and
 	# implicitly export all symbols.
 	# This should be the same for all languages, so no per-tag cache variable.
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the $host_os linker accepts -exported_symbol" >&5
-$as_echo_n "checking whether the $host_os linker accepts -exported_symbol... " >&6; }
-if ${lt_cv_irix_exported_symbol+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  save_LDFLAGS=$LDFLAGS
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the $host_os linker accepts -exported_symbol" >&5
+printf %s "checking whether the $host_os linker accepts -exported_symbol... " >&6; }
+if test ${lt_cv_irix_exported_symbol+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) save_LDFLAGS=$LDFLAGS
 	   LDFLAGS="$LDFLAGS -shared $wl-exported_symbol ${wl}foo $wl-update_registry $wl/dev/null"
 	   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 int foo (void) { return 0; }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   lt_cv_irix_exported_symbol=yes
-else
-  lt_cv_irix_exported_symbol=no
+else case e in #(
+  e) lt_cv_irix_exported_symbol=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-           LDFLAGS=$save_LDFLAGS
+           LDFLAGS=$save_LDFLAGS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_irix_exported_symbol" >&5
-$as_echo "$lt_cv_irix_exported_symbol" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_irix_exported_symbol" >&5
+printf "%s\n" "$lt_cv_irix_exported_symbol" >&6; }
 	if test yes = "$lt_cv_irix_exported_symbol"; then
           archive_expsym_cmds='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-soname $wl$soname `test -n "$verstring" && func_echo_all "$wl-set_version $wl$verstring"` $wl-update_registry $wl$output_objdir/so_locations $wl-exports_file $wl$export_symbols -o $lib'
 	fi
@@ -10516,6 +11532,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       old_archive_From_new_cmds='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       enable_shared_with_static_runtimes=yes
+      file_list_spec='@'
       ;;
 
     osf3*)
@@ -10704,8 +11721,8 @@
     fi
   fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ld_shlibs" >&5
-$as_echo "$ld_shlibs" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ld_shlibs" >&5
+printf "%s\n" "$ld_shlibs" >&6; }
 test no = "$ld_shlibs" && can_build_shared=no
 
 with_gnu_ld=$with_gnu_ld
@@ -10741,18 +11758,19 @@
       # Test whether the compiler implicitly links with -lc since on some
       # systems, -lgcc has to come before -lc. If gcc already passes -lc
       # to ld, don't add -lc before -lgcc.
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether -lc should be explicitly linked in" >&5
-$as_echo_n "checking whether -lc should be explicitly linked in... " >&6; }
-if ${lt_cv_archive_cmds_need_lc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  $RM conftest*
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether -lc should be explicitly linked in" >&5
+printf %s "checking whether -lc should be explicitly linked in... " >&6; }
+if test ${lt_cv_archive_cmds_need_lc+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) $RM conftest*
 	echo "$lt_simple_compile_test_code" > conftest.$ac_ext
 
 	if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
   (eval $ac_compile) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } 2>conftest.err; then
 	  soname=conftest
 	  lib=conftest
@@ -10770,7 +11788,7 @@
 	  if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$archive_cmds 2\>\&1 \| $GREP \" -lc \" \>/dev/null 2\>\&1\""; } >&5
   (eval $archive_cmds 2\>\&1 \| $GREP \" -lc \" \>/dev/null 2\>\&1) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }
 	  then
 	    lt_cv_archive_cmds_need_lc=no
@@ -10782,10 +11800,11 @@
 	  cat conftest.err 1>&5
 	fi
 	$RM conftest*
-
+	 ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_archive_cmds_need_lc" >&5
-$as_echo "$lt_cv_archive_cmds_need_lc" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_archive_cmds_need_lc" >&5
+printf "%s\n" "$lt_cv_archive_cmds_need_lc" >&6; }
       archive_cmds_need_lc=$lt_cv_archive_cmds_need_lc
       ;;
     esac
@@ -10944,8 +11963,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking dynamic linker characteristics" >&5
-$as_echo_n "checking dynamic linker characteristics... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking dynamic linker characteristics" >&5
+printf %s "checking dynamic linker characteristics... " >&6; }
 
 if test yes = "$GCC"; then
   case $host_os in
@@ -11207,7 +12226,7 @@
     case $host_os in
     cygwin*)
       # Cygwin DLLs use 'cyg' prefix rather than 'lib'
-      soname_spec='`echo $libname | sed -e 's/^lib/cyg/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
+      soname_spec='`echo $libname | $SED -e 's/^lib/cyg/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
 
       sys_lib_search_path_spec="$sys_lib_search_path_spec /usr/lib/w32api"
       ;;
@@ -11217,14 +12236,14 @@
       ;;
     pw32*)
       # pw32 DLLs use 'pw' prefix rather than 'lib'
-      library_names_spec='`echo $libname | sed -e 's/^lib/pw/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
+      library_names_spec='`echo $libname | $SED -e 's/^lib/pw/'``echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
       ;;
     esac
     dynamic_linker='Win32 ld.exe'
     ;;
 
-  *,cl*)
-    # Native MSVC
+  *,cl* | *,icl*)
+    # Native MSVC or ICC
     libname_spec='$name'
     soname_spec='$libname`echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext'
     library_names_spec='$libname.dll.lib'
@@ -11243,7 +12262,7 @@
       done
       IFS=$lt_save_ifs
       # Convert to MSYS style.
-      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | sed -e 's|\\\\|/|g' -e 's| \\([a-zA-Z]\\):| /\\1|g' -e 's|^ ||'`
+      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | $SED -e 's|\\\\|/|g' -e 's| \\([a-zA-Z]\\):| /\\1|g' -e 's|^ ||'`
       ;;
     cygwin*)
       # Convert to unix form, then to dos form, then back to unix form
@@ -11280,7 +12299,7 @@
     ;;
 
   *)
-    # Assume MSVC wrapper
+    # Assume MSVC and ICC wrapper
     library_names_spec='$libname`echo $release | $SED -e 's/[.]/-/g'`$versuffix$shared_ext $libname.lib'
     dynamic_linker='Win32 ld.exe'
     ;;
@@ -11313,7 +12332,7 @@
   shlibpath_var=LD_LIBRARY_PATH
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   # DragonFly does not have aout.  When/if they implement a new
   # versioning mechanism, adjust this.
   if test -x /usr/bin/objformat; then
@@ -11506,10 +12525,11 @@
   shlibpath_overrides_runpath=no
 
   # Some binutils ld are patched to set DT_RUNPATH
-  if ${lt_cv_shlibpath_overrides_runpath+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  lt_cv_shlibpath_overrides_runpath=no
+  if test ${lt_cv_shlibpath_overrides_runpath+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) lt_cv_shlibpath_overrides_runpath=no
     save_LDFLAGS=$LDFLAGS
     save_libdir=$libdir
     eval "libdir=/foo; wl=\"$lt_prog_compiler_wl\"; \
@@ -11518,23 +12538,26 @@
 /* end confdefs.h.  */
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  if  ($OBJDUMP -p conftest$ac_exeext) 2>/dev/null | grep "RUNPATH.*$libdir" >/dev/null; then :
+if ac_fn_c_try_link "$LINENO"
+then :
+  if  ($OBJDUMP -p conftest$ac_exeext) 2>/dev/null | grep "RUNPATH.*$libdir" >/dev/null
+then :
   lt_cv_shlibpath_overrides_runpath=yes
 fi
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
     LDFLAGS=$save_LDFLAGS
     libdir=$save_libdir
-
+     ;;
+esac
 fi
 
   shlibpath_overrides_runpath=$lt_cv_shlibpath_overrides_runpath
@@ -11762,8 +12785,8 @@
   dynamic_linker=no
   ;;
 esac
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $dynamic_linker" >&5
-$as_echo "$dynamic_linker" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $dynamic_linker" >&5
+printf "%s\n" "$dynamic_linker" >&6; }
 test no = "$dynamic_linker" && can_build_shared=no
 
 variables_saved_for_relink="PATH $shlibpath_var $runpath_var"
@@ -11884,8 +12907,8 @@
 
 
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking how to hardcode library paths into programs" >&5
-$as_echo_n "checking how to hardcode library paths into programs... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking how to hardcode library paths into programs" >&5
+printf %s "checking how to hardcode library paths into programs... " >&6; }
 hardcode_action=
 if test -n "$hardcode_libdir_flag_spec" ||
    test -n "$runpath_var" ||
@@ -11909,8 +12932,8 @@
   # directories.
   hardcode_action=unsupported
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $hardcode_action" >&5
-$as_echo "$hardcode_action" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $hardcode_action" >&5
+printf "%s\n" "$hardcode_action" >&6; }
 
 if test relink = "$hardcode_action" ||
    test yes = "$inherit_rpath"; then
@@ -11954,50 +12977,59 @@
 
   darwin*)
     # if libdl is installed we need to link against it
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
-$as_echo_n "checking for dlopen in -ldl... " >&6; }
-if ${ac_cv_lib_dl_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
+printf %s "checking for dlopen in -ldl... " >&6; }
+if test ${ac_cv_lib_dl_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldl  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char dlopen ();
+char dlopen (void);
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dl_dlopen=yes
-else
-  ac_cv_lib_dl_dlopen=no
+else case e in #(
+  e) ac_cv_lib_dl_dlopen=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
-$as_echo "$ac_cv_lib_dl_dlopen" >&6; }
-if test "x$ac_cv_lib_dl_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_dl_dlopen" >&6; }
+if test "x$ac_cv_lib_dl_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-ldl
-else
-
+else case e in #(
+  e)
     lt_cv_dlopen=dyld
     lt_cv_dlopen_libs=
     lt_cv_dlopen_self=yes
-
+     ;;
+esac
 fi
 
     ;;
@@ -12012,183 +13044,222 @@
 
   *)
     ac_fn_c_check_func "$LINENO" "shl_load" "ac_cv_func_shl_load"
-if test "x$ac_cv_func_shl_load" = xyes; then :
+if test "x$ac_cv_func_shl_load" = xyes
+then :
   lt_cv_dlopen=shl_load
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for shl_load in -ldld" >&5
-$as_echo_n "checking for shl_load in -ldld... " >&6; }
-if ${ac_cv_lib_dld_shl_load+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for shl_load in -ldld" >&5
+printf %s "checking for shl_load in -ldld... " >&6; }
+if test ${ac_cv_lib_dld_shl_load+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char shl_load ();
+char shl_load (void);
 int
-main ()
+main (void)
 {
 return shl_load ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dld_shl_load=yes
-else
-  ac_cv_lib_dld_shl_load=no
+else case e in #(
+  e) ac_cv_lib_dld_shl_load=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_shl_load" >&5
-$as_echo "$ac_cv_lib_dld_shl_load" >&6; }
-if test "x$ac_cv_lib_dld_shl_load" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_shl_load" >&5
+printf "%s\n" "$ac_cv_lib_dld_shl_load" >&6; }
+if test "x$ac_cv_lib_dld_shl_load" = xyes
+then :
   lt_cv_dlopen=shl_load lt_cv_dlopen_libs=-ldld
-else
-  ac_fn_c_check_func "$LINENO" "dlopen" "ac_cv_func_dlopen"
-if test "x$ac_cv_func_dlopen" = xyes; then :
+else case e in #(
+  e) ac_fn_c_check_func "$LINENO" "dlopen" "ac_cv_func_dlopen"
+if test "x$ac_cv_func_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
-$as_echo_n "checking for dlopen in -ldl... " >&6; }
-if ${ac_cv_lib_dl_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -ldl" >&5
+printf %s "checking for dlopen in -ldl... " >&6; }
+if test ${ac_cv_lib_dl_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldl  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char dlopen ();
+char dlopen (void);
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dl_dlopen=yes
-else
-  ac_cv_lib_dl_dlopen=no
+else case e in #(
+  e) ac_cv_lib_dl_dlopen=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
-$as_echo "$ac_cv_lib_dl_dlopen" >&6; }
-if test "x$ac_cv_lib_dl_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dl_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_dl_dlopen" >&6; }
+if test "x$ac_cv_lib_dl_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-ldl
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dlopen in -lsvld" >&5
-$as_echo_n "checking for dlopen in -lsvld... " >&6; }
-if ${ac_cv_lib_svld_dlopen+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dlopen in -lsvld" >&5
+printf %s "checking for dlopen in -lsvld... " >&6; }
+if test ${ac_cv_lib_svld_dlopen+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-lsvld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char dlopen ();
+char dlopen (void);
 int
-main ()
+main (void)
 {
 return dlopen ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_svld_dlopen=yes
-else
-  ac_cv_lib_svld_dlopen=no
+else case e in #(
+  e) ac_cv_lib_svld_dlopen=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_svld_dlopen" >&5
-$as_echo "$ac_cv_lib_svld_dlopen" >&6; }
-if test "x$ac_cv_lib_svld_dlopen" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_svld_dlopen" >&5
+printf "%s\n" "$ac_cv_lib_svld_dlopen" >&6; }
+if test "x$ac_cv_lib_svld_dlopen" = xyes
+then :
   lt_cv_dlopen=dlopen lt_cv_dlopen_libs=-lsvld
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for dld_link in -ldld" >&5
-$as_echo_n "checking for dld_link in -ldld... " >&6; }
-if ${ac_cv_lib_dld_dld_link+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for dld_link in -ldld" >&5
+printf %s "checking for dld_link in -ldld... " >&6; }
+if test ${ac_cv_lib_dld_dld_link+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-ldld  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char dld_link ();
+char dld_link (void);
 int
-main ()
+main (void)
 {
 return dld_link ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_dld_dld_link=yes
-else
-  ac_cv_lib_dld_dld_link=no
+else case e in #(
+  e) ac_cv_lib_dld_dld_link=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_dld_link" >&5
-$as_echo "$ac_cv_lib_dld_dld_link" >&6; }
-if test "x$ac_cv_lib_dld_dld_link" = xyes; then :
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_dld_dld_link" >&5
+printf "%s\n" "$ac_cv_lib_dld_dld_link" >&6; }
+if test "x$ac_cv_lib_dld_dld_link" = xyes
+then :
   lt_cv_dlopen=dld_link lt_cv_dlopen_libs=-ldld
 fi
 
-
+	       ;;
+esac
 fi
 
-
+	     ;;
+esac
 fi
 
-
+	   ;;
+esac
 fi
 
-
+	 ;;
+esac
 fi
 
-
+       ;;
+esac
 fi
 
     ;;
@@ -12211,12 +13282,13 @@
     save_LIBS=$LIBS
     LIBS="$lt_cv_dlopen_libs $LIBS"
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether a program can dlopen itself" >&5
-$as_echo_n "checking whether a program can dlopen itself... " >&6; }
-if ${lt_cv_dlopen_self+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  	  if test yes = "$cross_compiling"; then :
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether a program can dlopen itself" >&5
+printf %s "checking whether a program can dlopen itself... " >&6; }
+if test ${lt_cv_dlopen_self+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) 	  if test yes = "$cross_compiling"; then :
   lt_cv_dlopen_self=cross
 else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
@@ -12294,7 +13366,7 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "conftest$ac_exeext" 2>/dev/null; then
     (./conftest; exit; ) >&5 2>/dev/null
     lt_status=$?
@@ -12310,19 +13382,21 @@
 fi
 rm -fr conftest*
 
-
+     ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self" >&5
-$as_echo "$lt_cv_dlopen_self" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self" >&5
+printf "%s\n" "$lt_cv_dlopen_self" >&6; }
 
     if test yes = "$lt_cv_dlopen_self"; then
       wl=$lt_prog_compiler_wl eval LDFLAGS=\"\$LDFLAGS $lt_prog_compiler_static\"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether a statically linked program can dlopen itself" >&5
-$as_echo_n "checking whether a statically linked program can dlopen itself... " >&6; }
-if ${lt_cv_dlopen_self_static+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  	  if test yes = "$cross_compiling"; then :
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether a statically linked program can dlopen itself" >&5
+printf %s "checking whether a statically linked program can dlopen itself... " >&6; }
+if test ${lt_cv_dlopen_self_static+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) 	  if test yes = "$cross_compiling"; then :
   lt_cv_dlopen_self_static=cross
 else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
@@ -12400,7 +13474,7 @@
   if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_link\""; } >&5
   (eval $ac_link) 2>&5
   ac_status=$?
-  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; } && test -s "conftest$ac_exeext" 2>/dev/null; then
     (./conftest; exit; ) >&5 2>/dev/null
     lt_status=$?
@@ -12416,10 +13490,11 @@
 fi
 rm -fr conftest*
 
-
+       ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self_static" >&5
-$as_echo "$lt_cv_dlopen_self_static" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $lt_cv_dlopen_self_static" >&5
+printf "%s\n" "$lt_cv_dlopen_self_static" >&6; }
     fi
 
     CPPFLAGS=$save_CPPFLAGS
@@ -12457,32 +13532,43 @@
 
 striplib=
 old_striplib=
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether stripping libraries is possible" >&5
-$as_echo_n "checking whether stripping libraries is possible... " >&6; }
-if test -n "$STRIP" && $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
-  test -z "$old_striplib" && old_striplib="$STRIP --strip-debug"
-  test -z "$striplib" && striplib="$STRIP --strip-unneeded"
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether stripping libraries is possible" >&5
+printf %s "checking whether stripping libraries is possible... " >&6; }
+if test -z "$STRIP"; then
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 else
-# FIXME - insert some real tests, host_os isn't really good enough
-  case $host_os in
-  darwin*)
-    if test -n "$STRIP"; then
+  if $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
+    old_striplib="$STRIP --strip-debug"
+    striplib="$STRIP --strip-unneeded"
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+  else
+    case $host_os in
+    darwin*)
+      # FIXME - insert some real tests, host_os isn't really good enough
       striplib="$STRIP -x"
       old_striplib="$STRIP -S"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-    else
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    fi
-    ;;
-  *)
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    ;;
-  esac
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+      ;;
+    freebsd*)
+      if $STRIP -V 2>&1 | $GREP "elftoolchain" >/dev/null; then
+        old_striplib="$STRIP --strip-debug"
+        striplib="$STRIP --strip-unneeded"
+        { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
+      else
+        { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+      fi
+      ;;
+    *)
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+      ;;
+    esac
+  fi
 fi
 
 
@@ -12497,13 +13583,13 @@
 
 
   # Report what library types will actually be built
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking if libtool supports shared libraries" >&5
-$as_echo_n "checking if libtool supports shared libraries... " >&6; }
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $can_build_shared" >&5
-$as_echo "$can_build_shared" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if libtool supports shared libraries" >&5
+printf %s "checking if libtool supports shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $can_build_shared" >&5
+printf "%s\n" "$can_build_shared" >&6; }
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to build shared libraries" >&5
-$as_echo_n "checking whether to build shared libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to build shared libraries" >&5
+printf %s "checking whether to build shared libraries... " >&6; }
   test no = "$can_build_shared" && enable_shared=no
 
   # On AIX, shared libraries and static libraries use the same namespace, and
@@ -12527,15 +13613,15 @@
     fi
     ;;
   esac
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_shared" >&5
-$as_echo "$enable_shared" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $enable_shared" >&5
+printf "%s\n" "$enable_shared" >&6; }
 
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to build static libraries" >&5
-$as_echo_n "checking whether to build static libraries... " >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to build static libraries" >&5
+printf %s "checking whether to build static libraries... " >&6; }
   # Make sure either enable_shared or enable_static is yes.
   test yes = "$enable_shared" || enable_static=yes
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_static" >&5
-$as_echo "$enable_static" >&6; }
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $enable_static" >&5
+printf "%s\n" "$enable_static" >&6; }
 
 
 
@@ -12575,19 +13661,19 @@
 
 # Some awks crash when confronted with pnglibconf.dfa, do a test run now
 # to make sure this doesn't happen
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking that AWK works" >&5
-$as_echo_n "checking that AWK works... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking that AWK works" >&5
+printf %s "checking that AWK works... " >&6; }
 if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
    ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
    ${srcdir}/pngusr.dfa 1>&2
 then
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: ok" >&5
-$as_echo "ok" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: ok" >&5
+printf "%s\n" "ok" >&6; }
 else
-   { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+   { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error 1 "failed
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; }
 fi
 
 # This is a remnant of the old cc -E validation, where it may have been
@@ -12595,18 +13681,57 @@
 DFNCPP="$CPP"
 
 
-# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
-# checks the compiler with a program that generates a warning), add the
-# following option to deal with this
+# Check whether --enable-tests was given.
+if test ${enable_tests+y}
+then :
+  enableval=$enable_tests; enable_tests="$enableval"
+else case e in #(
+  e) enable_tests=yes ;;
+esac
+fi
+
+
+ if test "$enable_tests" != "no"; then
+  ENABLE_TESTS_TRUE=
+  ENABLE_TESTS_FALSE='#'
+else
+  ENABLE_TESTS_TRUE='#'
+  ENABLE_TESTS_FALSE=
+fi
+
+
+# Check whether --enable-tools was given.
+if test ${enable_tools+y}
+then :
+  enableval=$enable_tools; enable_tools="$enableval"
+else case e in #(
+  e) enable_tools=yes ;;
+esac
+fi
+
+
+ if test "$enable_tools" != "no"; then
+  ENABLE_TOOLS_TRUE=
+  ENABLE_TOOLS_FALSE='#'
+else
+  ENABLE_TOOLS_TRUE='#'
+  ENABLE_TOOLS_FALSE=
+fi
+
+
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail
+# (it checks the compiler with a program that generates a warning).
+# Add the following option to deal with this:
 
 # Check whether --enable-werror was given.
-if test "${enable_werror+set}" = set; then :
+if test ${enable_werror+y}
+then :
   enableval=$enable_werror; test "$enable_werror" = "yes" && enable_werror="-Werror"
     if test "$enable_werror" != "no"; then
       sav_CFLAGS="$CFLAGS"
       CFLAGS="$enable_werror $CFLAGS"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking if the compiler allows $enable_werror" >&5
-$as_echo_n "checking if the compiler allows $enable_werror... " >&6; }
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if the compiler allows $enable_werror" >&5
+printf %s "checking if the compiler allows $enable_werror... " >&6; }
       cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -12614,26 +13739,28 @@
             return argv[argc-1][0];
             }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+if ac_fn_c_try_compile "$LINENO"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
          PNG_COPTS="$PNG_COPTS $enable_werror"
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; } ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
       CFLAGS="$sav_CFLAGS"
     fi
 fi
 
 
-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the
-# "-std=c89" compiler option:
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if we need to force back C standard to C89" >&5
-$as_echo_n "checking if we need to force back C standard to C89... " >&6; }
+# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89.
+# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining
+# _POSIX_SOURCE to 1. This is incompatible with the new default mode, so
+# we test for that and force the "-std=c89" compiler option:
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if we need to force back C standard to C89" >&5
+printf %s "checking if we need to force back C standard to C89... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -12641,247 +13768,44 @@
       #include <stdio.h>
 
 int
-main ()
+main (void)
 {
 
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-else
-
+if ac_fn_c_try_compile "$LINENO"
+then :
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+else case e in #(
+  e)
       if test "x$GCC" != "xyes"; then
          as_fn_error $? "Forcing back to C89 is required but the flags are only known for GCC" "$LINENO" 5
       fi
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
    CFLAGS="$CFLAGS -std=c89"
-
+ ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
 
-# Checks for header files.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
-$as_echo_n "checking for ANSI C header files... " >&6; }
-if ${ac_cv_header_stdc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-int
-main ()
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_header_stdc=yes
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "memchr" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "free" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then :
-  :
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <ctype.h>
-#include <stdlib.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) \
-		   (('a' <= (c) && (c) <= 'i') \
-		     || ('j' <= (c) && (c) <= 'r') \
-		     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-	|| toupper (i) != TOUPPER (i))
-      return 2;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
-$as_echo "$ac_cv_header_stdc" >&6; }
-if test $ac_cv_header_stdc = yes; then
-
-$as_echo "#define STDC_HEADERS 1" >>confdefs.h
-
-fi
-
-
-# Checks for typedefs, structures, and compiler characteristics.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for an ANSI C-conforming const" >&5
-$as_echo_n "checking for an ANSI C-conforming const... " >&6; }
-if ${ac_cv_c_const+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-int
-main ()
-{
-
-#ifndef __cplusplus
-  /* Ultrix mips cc rejects this sort of thing.  */
-  typedef int charset[2];
-  const charset cs = { 0, 0 };
-  /* SunOS 4.1.1 cc rejects this.  */
-  char const *const *pcpcc;
-  char **ppc;
-  /* NEC SVR4.0.2 mips cc rejects this.  */
-  struct point {int x, y;};
-  static struct point const zero = {0,0};
-  /* AIX XL C 1.02.0.0 rejects this.
-     It does not let you subtract one const X* pointer from another in
-     an arm of an if-expression whose if-part is not a constant
-     expression */
-  const char *g = "string";
-  pcpcc = &g + (g ? g-g : 0);
-  /* HPUX 7.0 cc rejects these. */
-  ++pcpcc;
-  ppc = (char**) pcpcc;
-  pcpcc = (char const *const *) ppc;
-  { /* SCO 3.2v4 cc rejects this sort of thing.  */
-    char tx;
-    char *t = &tx;
-    char const *s = 0 ? (char *) 0 : (char const *) 0;
-
-    *t++ = 0;
-    if (s) return 0;
-  }
-  { /* Someone thinks the Sun supposedly-ANSI compiler will reject this.  */
-    int x[] = {25, 17};
-    const int *foo = &x[0];
-    ++foo;
-  }
-  { /* Sun SC1.0 ANSI compiler rejects this -- but not the above. */
-    typedef const int *iptr;
-    iptr p = 0;
-    ++p;
-  }
-  { /* AIX XL C 1.02.0.0 rejects this sort of thing, saying
-       "k.c", line 2.27: 1506-025 (S) Operand must be a modifiable lvalue. */
-    struct s { int j; const int *ap[3]; } bx;
-    struct s *b = &bx; b->j = 5;
-  }
-  { /* ULTRIX-32 V3.1 (Rev 9) vcc rejects this */
-    const int foo = 10;
-    if (!foo) return 0;
-  }
-  return !cs[0] && !zero.x;
-#endif
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_c_const=yes
-else
-  ac_cv_c_const=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_const" >&5
-$as_echo "$ac_cv_c_const" >&6; }
-if test $ac_cv_c_const = no; then
-
-$as_echo "#define const /**/" >>confdefs.h
-
-fi
-
-ac_fn_c_check_type "$LINENO" "size_t" "ac_cv_type_size_t" "$ac_includes_default"
-if test "x$ac_cv_type_size_t" = xyes; then :
-
-else
-
-cat >>confdefs.h <<_ACEOF
-#define size_t unsigned int
-_ACEOF
-
-fi
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether struct tm is in sys/time.h or time.h" >&5
-$as_echo_n "checking whether struct tm is in sys/time.h or time.h... " >&6; }
-if ${ac_cv_struct_tm+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+# Checks for structures and compiler characteristics.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether struct tm is in sys/time.h or time.h" >&5
+printf %s "checking whether struct tm is in sys/time.h or time.h... " >&6; }
+if test ${ac_cv_struct_tm+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 #include <sys/types.h>
 #include <time.h>
 
 int
-main ()
+main (void)
 {
 struct tm tm;
 				     int *p = &tm.tm_sec;
@@ -12890,250 +13814,155 @@
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_struct_tm=time.h
-else
-  ac_cv_struct_tm=sys/time.h
+else case e in #(
+  e) ac_cv_struct_tm=sys/time.h ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_struct_tm" >&5
-$as_echo "$ac_cv_struct_tm" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_struct_tm" >&5
+printf "%s\n" "$ac_cv_struct_tm" >&6; }
 if test $ac_cv_struct_tm = sys/time.h; then
 
-$as_echo "#define TM_IN_SYS_TIME 1" >>confdefs.h
+printf "%s\n" "#define TM_IN_SYS_TIME 1" >>confdefs.h
 
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5
-$as_echo_n "checking for C/C++ restrict keyword... " >&6; }
-if ${ac_cv_c_restrict+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_cv_c_restrict=no
-   # The order here caters to the fact that C++ does not require restrict.
-   for ac_kw in __restrict __restrict__ _Restrict restrict; do
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for C/C++ restrict keyword" >&5
+printf %s "checking for C/C++ restrict keyword... " >&6; }
+if test ${ac_cv_c_restrict+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_cv_c_restrict=no
+   # Put '__restrict__' first, to avoid problems with glibc and non-GCC; see:
+   # https://lists.gnu.org/archive/html/bug-autoconf/2016-02/msg00006.html
+   # Put 'restrict' last, because C++ lacks it.
+   for ac_kw in __restrict__ __restrict _Restrict restrict; do
      cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
-typedef int * int_ptr;
-	int foo (int_ptr $ac_kw ip) {
-	return ip[0];
-       }
+typedef int *int_ptr;
+	   int foo (int_ptr $ac_kw ip) { return ip[0]; }
+	   int bar (int [$ac_kw]); /* Catch GCC bug 14050.  */
+	   int bar (int ip[$ac_kw]) { return ip[0]; }
+
 int
-main ()
+main (void)
 {
 int s[1];
-	int * $ac_kw t = s;
-	t[0] = 0;
-	return foo(t)
+	   int *$ac_kw t = s;
+	   t[0] = 0;
+	   return foo (t) + bar (t);
+
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
+if ac_fn_c_try_compile "$LINENO"
+then :
   ac_cv_c_restrict=$ac_kw
 fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
      test "$ac_cv_c_restrict" != no && break
    done
-
+   ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_restrict" >&5
-$as_echo "$ac_cv_c_restrict" >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_c_restrict" >&5
+printf "%s\n" "$ac_cv_c_restrict" >&6; }
 
  case $ac_cv_c_restrict in
    restrict) ;;
-   no) $as_echo "#define restrict /**/" >>confdefs.h
+   no) printf "%s\n" "#define restrict /**/" >>confdefs.h
  ;;
-   *)  cat >>confdefs.h <<_ACEOF
-#define restrict $ac_cv_c_restrict
-_ACEOF
+   *)  printf "%s\n" "#define restrict $ac_cv_c_restrict" >>confdefs.h
  ;;
  esac
 
 
 # Checks for library functions.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for working strtod" >&5
-$as_echo_n "checking for working strtod... " >&6; }
-if ${ac_cv_func_strtod+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test "$cross_compiling" = yes; then :
-  ac_cv_func_strtod=no
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
 
-$ac_includes_default
-#ifndef strtod
-double strtod ();
-#endif
-int
-main()
-{
-  {
-    /* Some versions of Linux strtod mis-parse strings with leading '+'.  */
-    char *string = " +69";
-    char *term;
-    double value;
-    value = strtod (string, &term);
-    if (value != 69 || term != (string + 4))
-      return 1;
-  }
-
-  {
-    /* Under Solaris 2.4, strtod returns the wrong value for the
-       terminating character under some conditions.  */
-    char *string = "NaN";
-    char *term;
-    strtod (string, &term);
-    if (term != string && *(term - 1) == 0)
-      return 1;
-  }
-  return 0;
-}
-
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-  ac_cv_func_strtod=yes
-else
-  ac_cv_func_strtod=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_func_strtod" >&5
-$as_echo "$ac_cv_func_strtod" >&6; }
-if test $ac_cv_func_strtod = no; then
-  case " $LIBOBJS " in
-  *" strtod.$ac_objext "* ) ;;
-  *) LIBOBJS="$LIBOBJS strtod.$ac_objext"
- ;;
-esac
-
-ac_fn_c_check_func "$LINENO" "pow" "ac_cv_func_pow"
-if test "x$ac_cv_func_pow" = xyes; then :
-
-fi
-
-if test $ac_cv_func_pow = no; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
-$as_echo_n "checking for pow in -lm... " >&6; }
-if ${ac_cv_lib_m_pow+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
-LIBS="-lm  $LIBS"
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-/* Override any GCC internal prototype to avoid an error.
-   Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
-char pow ();
-int
-main ()
-{
-return pow ();
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  ac_cv_lib_m_pow=yes
-else
-  ac_cv_lib_m_pow=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
-$as_echo "$ac_cv_lib_m_pow" >&6; }
-if test "x$ac_cv_lib_m_pow" = xyes; then :
-  POW_LIB=-lm
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cannot find library containing definition of pow" >&5
-$as_echo "$as_me: WARNING: cannot find library containing definition of pow" >&2;}
-fi
-
-fi
-
-fi
-
-for ac_func in pow
+  for ac_func in pow
 do :
   ac_fn_c_check_func "$LINENO" "pow" "ac_cv_func_pow"
-if test "x$ac_cv_func_pow" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_POW 1
-_ACEOF
+if test "x$ac_cv_func_pow" = xyes
+then :
+  printf "%s\n" "#define HAVE_POW 1" >>confdefs.h
 
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
-$as_echo_n "checking for pow in -lm... " >&6; }
-if ${ac_cv_lib_m_pow+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for pow in -lm" >&5
+printf %s "checking for pow in -lm... " >&6; }
+if test ${ac_cv_lib_m_pow+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-lm  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char pow ();
+char pow (void);
 int
-main ()
+main (void)
 {
 return pow ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_m_pow=yes
-else
-  ac_cv_lib_m_pow=no
+else case e in #(
+  e) ac_cv_lib_m_pow=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
-$as_echo "$ac_cv_lib_m_pow" >&6; }
-if test "x$ac_cv_lib_m_pow" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBM 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_pow" >&5
+printf "%s\n" "$ac_cv_lib_m_pow" >&6; }
+if test "x$ac_cv_lib_m_pow" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBM 1" >>confdefs.h
 
   LIBS="-lm $LIBS"
 
-else
-  as_fn_error $? "cannot find pow" "$LINENO" 5
+else case e in #(
+  e) as_fn_error $? "cannot find pow" "$LINENO" 5 ;;
+esac
+fi
+ ;;
+esac
 fi
 
-fi
 done
 
-
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
+# Some later POSIX 1003.1 functions are required for test programs, failure
+# here is soft (the corresponding test program is not built).
 ac_fn_c_check_func "$LINENO" "clock_gettime" "ac_cv_func_clock_gettime"
-if test "x$ac_cv_func_clock_gettime" = xyes; then :
+if test "x$ac_cv_func_clock_gettime" = xyes
+then :
 
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: not building timepng" >&5
-$as_echo "$as_me: WARNING: not building timepng" >&2;}
+else case e in #(
+  e) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: not building timepng" >&5
+printf "%s\n" "$as_me: WARNING: not building timepng" >&2;} ;;
+esac
 fi
 
  if test "$ac_cv_func_clock_gettime" = "yes"; then
@@ -13147,179 +13976,197 @@
 
 
 # Check whether --with-zlib-prefix was given.
-if test "${with_zlib_prefix+set}" = set; then :
+if test ${with_zlib_prefix+y}
+then :
   withval=$with_zlib_prefix; ZPREFIX=${withval}
-else
-  ZPREFIX='z_'
+else case e in #(
+  e) ZPREFIX='z_' ;;
+esac
 fi
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for zlibVersion in -lz" >&5
-$as_echo_n "checking for zlibVersion in -lz... " >&6; }
-if ${ac_cv_lib_z_zlibVersion+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for zlibVersion in -lz" >&5
+printf %s "checking for zlibVersion in -lz... " >&6; }
+if test ${ac_cv_lib_z_zlibVersion+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-lz  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char zlibVersion ();
+char zlibVersion (void);
 int
-main ()
+main (void)
 {
 return zlibVersion ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_z_zlibVersion=yes
-else
-  ac_cv_lib_z_zlibVersion=no
+else case e in #(
+  e) ac_cv_lib_z_zlibVersion=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_z_zlibVersion" >&5
-$as_echo "$ac_cv_lib_z_zlibVersion" >&6; }
-if test "x$ac_cv_lib_z_zlibVersion" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBZ 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_z_zlibVersion" >&5
+printf "%s\n" "$ac_cv_lib_z_zlibVersion" >&6; }
+if test "x$ac_cv_lib_z_zlibVersion" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBZ 1" >>confdefs.h
 
   LIBS="-lz $LIBS"
 
-else
-  as_ac_Lib=`$as_echo "ac_cv_lib_z_${ZPREFIX}zlibVersion" | $as_tr_sh`
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${ZPREFIX}zlibVersion in -lz" >&5
-$as_echo_n "checking for ${ZPREFIX}zlibVersion in -lz... " >&6; }
-if eval \${$as_ac_Lib+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+else case e in #(
+  e) as_ac_Lib=`printf "%s\n" "ac_cv_lib_z_${ZPREFIX}zlibVersion" | sed "$as_sed_sh"`
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for ${ZPREFIX}zlibVersion in -lz" >&5
+printf %s "checking for ${ZPREFIX}zlibVersion in -lz... " >&6; }
+if eval test \${$as_ac_Lib+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-lz  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char ${ZPREFIX}zlibVersion ();
+char ${ZPREFIX}zlibVersion (void);
 int
-main ()
+main (void)
 {
 return ${ZPREFIX}zlibVersion ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   eval "$as_ac_Lib=yes"
-else
-  eval "$as_ac_Lib=no"
+else case e in #(
+  e) eval "$as_ac_Lib=no" ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
 eval ac_res=\$$as_ac_Lib
-	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
-$as_echo "$ac_res" >&6; }
-if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBZ 1
-_ACEOF
+	       { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+printf "%s\n" "$ac_res" >&6; }
+if eval test \"x\$"$as_ac_Lib"\" = x"yes"
+then :
+  printf "%s\n" "#define HAVE_LIBZ 1" >>confdefs.h
 
   LIBS="-lz $LIBS"
 
-else
-  as_fn_error $? "zlib not installed" "$LINENO" 5
+else case e in #(
+  e) as_fn_error $? "zlib not installed" "$LINENO" 5 ;;
+esac
 fi
-
+ ;;
+esac
 fi
 
 
 # The following is for pngvalid, to ensure it catches FP errors even on
 # platforms that don't enable FP exceptions, the function appears in the math
 # library (typically), it's not an error if it is not found.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for feenableexcept in -lm" >&5
-$as_echo_n "checking for feenableexcept in -lm... " >&6; }
-if ${ac_cv_lib_m_feenableexcept+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for feenableexcept in -lm" >&5
+printf %s "checking for feenableexcept in -lm... " >&6; }
+if test ${ac_cv_lib_m_feenableexcept+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) ac_check_lib_save_LIBS=$LIBS
 LIBS="-lm  $LIBS"
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 /* Override any GCC internal prototype to avoid an error.
    Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
+   builtin and then its argument prototype would still apply.
+   The 'extern "C"' is for builds by C++ compilers;
+   although this is not generally supported in C code supporting it here
+   has little cost and some practical benefit (sr 110532).  */
 #ifdef __cplusplus
 extern "C"
 #endif
-char feenableexcept ();
+char feenableexcept (void);
 int
-main ()
+main (void)
 {
 return feenableexcept ();
   ;
   return 0;
 }
 _ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
+if ac_fn_c_try_link "$LINENO"
+then :
   ac_cv_lib_m_feenableexcept=yes
-else
-  ac_cv_lib_m_feenableexcept=no
+else case e in #(
+  e) ac_cv_lib_m_feenableexcept=no ;;
+esac
 fi
-rm -f core conftest.err conftest.$ac_objext \
+rm -f core conftest.err conftest.$ac_objext conftest.beam \
     conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
+LIBS=$ac_check_lib_save_LIBS ;;
+esac
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_feenableexcept" >&5
-$as_echo "$ac_cv_lib_m_feenableexcept" >&6; }
-if test "x$ac_cv_lib_m_feenableexcept" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBM 1
-_ACEOF
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_m_feenableexcept" >&5
+printf "%s\n" "$ac_cv_lib_m_feenableexcept" >&6; }
+if test "x$ac_cv_lib_m_feenableexcept" = xyes
+then :
+  printf "%s\n" "#define HAVE_LIBM 1" >>confdefs.h
 
   LIBS="-lm $LIBS"
 
 fi
 
-for ac_func in feenableexcept
-do :
-  ac_fn_c_check_func "$LINENO" "feenableexcept" "ac_cv_func_feenableexcept"
-if test "x$ac_cv_func_feenableexcept" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_FEENABLEEXCEPT 1
-_ACEOF
+ac_fn_c_check_func "$LINENO" "feenableexcept" "ac_cv_func_feenableexcept"
+if test "x$ac_cv_func_feenableexcept" = xyes
+then :
+  printf "%s\n" "#define HAVE_FEENABLEEXCEPT 1" >>confdefs.h
 
 fi
-done
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if using Solaris linker" >&5
-$as_echo_n "checking if using Solaris linker... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if using Solaris linker" >&5
+printf %s "checking if using Solaris linker... " >&6; }
 SLD=`$LD --version 2>&1 | grep Solaris`
 if test "$SLD"; then
     have_solaris_ld=yes
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
     have_solaris_ld=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 fi
  if test "$have_solaris_ld" = "yes"; then
   HAVE_SOLARIS_LD_TRUE=
@@ -13330,16 +14177,16 @@
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if libraries can be versioned" >&5
-$as_echo_n "checking if libraries can be versioned... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if libraries can be versioned" >&5
+printf %s "checking if libraries can be versioned... " >&6; }
 # Special case for PE/COFF platforms: ld reports
 # support for version-script, but doesn't actually
 # DO anything with it.
 case $host in
 *cygwin* | *mingw32* | *interix* )
     have_ld_version_script=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
 ;;
 * )
 
@@ -13351,14 +14198,14 @@
 
 if test "$GLD"; then
     have_ld_version_script=yes
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; }
 else
     have_ld_version_script=no
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-    { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: *** You have not enabled versioned symbols." >&5
-$as_echo "$as_me: WARNING: *** You have not enabled versioned symbols." >&2;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: *** You have not enabled versioned symbols." >&5
+printf "%s\n" "$as_me: WARNING: *** You have not enabled versioned symbols." >&2;}
 fi
 ;;
 esac
@@ -13373,15 +14220,15 @@
 
 
 if test "$have_ld_version_script" = "yes"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for symbol prefix" >&5
-$as_echo_n "checking for symbol prefix... " >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for symbol prefix" >&5
+printf %s "checking for symbol prefix... " >&6; }
     SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
                   | ${CPP-${CC-gcc} -E} - 2>&1 \
                   | ${EGREP-grep} "^PREFIX=" \
                   | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
 
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $SYMBOL_PREFIX" >&5
-$as_echo "$SYMBOL_PREFIX" >&6; }
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $SYMBOL_PREFIX" >&5
+printf "%s\n" "$SYMBOL_PREFIX" >&6; }
 fi
 
 # Substitutions for .in files
@@ -13394,30 +14241,34 @@
 # Allow the pkg-config directory to be set
 
 # Check whether --with-pkgconfigdir was given.
-if test "${with_pkgconfigdir+set}" = set; then :
+if test ${with_pkgconfigdir+y}
+then :
   withval=$with_pkgconfigdir; pkgconfigdir=${withval}
-else
-  pkgconfigdir='${libdir}/pkgconfig'
+else case e in #(
+  e) pkgconfigdir='${libdir}/pkgconfig' ;;
+esac
 fi
 
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: pkgconfig directory is ${pkgconfigdir}" >&5
-$as_echo "$as_me: pkgconfig directory is ${pkgconfigdir}" >&6;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: pkgconfig directory is ${pkgconfigdir}" >&5
+printf "%s\n" "$as_me: pkgconfig directory is ${pkgconfigdir}" >&6;}
 
 # Make the *-config binary config scripts optional
 
 # Check whether --with-binconfigs was given.
-if test "${with_binconfigs+set}" = set; then :
+if test ${with_binconfigs+y}
+then :
   withval=$with_binconfigs; if test "${withval}" = no; then
       binconfigs=
-      { $as_echo "$as_me:${as_lineno-$LINENO}: libpng-config scripts will not be built" >&5
-$as_echo "$as_me: libpng-config scripts will not be built" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: libpng-config scripts will not be built" >&5
+printf "%s\n" "$as_me: libpng-config scripts will not be built" >&6;}
     else
       binconfigs='${binconfigs}'
     fi
-else
-  binconfigs='${binconfigs}'
+else case e in #(
+  e) binconfigs='${binconfigs}' ;;
+esac
 fi
 
 
@@ -13426,7 +14277,8 @@
 # at the start of the build to rename exported library functions
 
 # Check whether --with-libpng-prefix was given.
-if test "${with_libpng_prefix+set}" = set; then :
+if test ${with_libpng_prefix+y}
+then :
   withval=$with_libpng_prefix; if test "${withval:-no}" != "no"; then
       PNG_PREFIX=${withval}
 
@@ -13446,7 +14298,8 @@
 # always installed, when the following options are turned on corresponding
 # unversioned links are also created (normally as symbolic links):
 # Check whether --enable-unversioned-links was given.
-if test "${enable_unversioned_links+set}" = set; then :
+if test ${enable_unversioned_links+y}
+then :
   enableval=$enable_unversioned_links;
 fi
 
@@ -13463,7 +14316,8 @@
 
 
 # Check whether --enable-unversioned-libpng-pc was given.
-if test "${enable_unversioned_libpng_pc+set}" = set; then :
+if test ${enable_unversioned_libpng_pc+y}
+then :
   enableval=$enable_unversioned_libpng_pc;
 fi
 
@@ -13477,7 +14331,8 @@
 
 
 # Check whether --enable-unversioned-libpng-config was given.
-if test "${enable_unversioned_libpng_config+set}" = set; then :
+if test ${enable_unversioned_libpng_config+y}
+then :
   enableval=$enable_unversioned_libpng_config;
 fi
 
@@ -13490,32 +14345,41 @@
 fi
 
 
-# HOST SPECIFIC OPTIONS
+# HOST-SPECIFIC OPTIONS
 # =====================
 #
 # DEFAULT
 # =======
 #
 # Check whether --enable-hardware-optimizations was given.
-if test "${enable_hardware_optimizations+set}" = set; then :
+if test ${enable_hardware_optimizations+y}
+then :
   enableval=$enable_hardware_optimizations; case "$enableval" in
       no|off)
          # disable hardware optimization on all systems:
          enable_arm_neon=no
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
 
          enable_mips_msa=no
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+
+         enable_mips_mmi=no
+
+printf "%s\n" "#define PNG_MIPS_MMI_OPT 0" >>confdefs.h
 
          enable_powerpc_vsx=no
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
 
          enable_intel_sse=no
 
-$as_echo "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
+
+         enable_loongarch_lsx=no
+
+printf "%s\n" "#define PNG_LOONGARCH_LSX_OPT 0" >>confdefs.h
 
          ;;
       *)
@@ -13524,25 +14388,35 @@
             arm*|aarch64*)
               enable_arm_neon=yes
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
 
               ;;
             mipsel*|mips64el*)
+              enable_mips_mmi=yes
               enable_mips_msa=yes
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MMI_OPT 1" >>confdefs.h
+
+
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
 
               ;;
             i?86|x86_64)
               enable_intel_sse=yes
 
-$as_echo "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
 
               ;;
             powerpc*|ppc64*)
               enable_powerpc_vsx=yes
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
+
+              ;;
+            loongarch*)
+              enable_loongarch_lsx=yes
+
+printf "%s\n" "#define PNG_LOONGARCH_LSX_OPT 1" >>confdefs.h
 
               ;;
          esac
@@ -13557,31 +14431,32 @@
 # ARM NEON (SIMD) support.
 
 # Check whether --enable-arm-neon was given.
-if test "${enable_arm_neon+set}" = set; then :
+if test ${enable_arm_neon+y}
+then :
   enableval=$enable_arm_neon; case "$enableval" in
       no|off)
          # disable the default enabling on __ARM_NEON__ systems:
 
-$as_echo "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_arm_neon=no;;
+         enable_arm_neon=no ;;
       check)
 
-$as_echo "#define PNG_ARM_NEON_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_CHECK_SUPPORTED /**/" >>confdefs.h
 ;;
       api)
 
-$as_echo "#define PNG_ARM_NEON_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_ARM_NEON_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass -mfpu=neon
             to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
+printf "%s\n" "$as_me: WARNING: --enable-arm-neon: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass -mfpu=neon
             to the compiler." >&2;};;
       *)
@@ -13590,14 +14465,14 @@
 fi
 
 
-# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
-# where ARM optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'arm*')
+# Add ARM-specific files to all builds where $host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'arm*')
 
  if test "$enable_arm_neon" != 'no' &&
     case "$host_cpu" in
-      arm*|aarch64*) :;;
-      *)    test "$enable_arm_neon" != '';;
+      arm*|aarch64*) : ;;
+      *)    test "$enable_arm_neon" != '' ;;
     esac; then
   PNG_ARM_NEON_TRUE=
   PNG_ARM_NEON_FALSE='#'
@@ -13608,36 +14483,37 @@
 
 
 # MIPS
-# ===
+# ====
 #
 # MIPS MSA (SIMD) support.
 
 # Check whether --enable-mips-msa was given.
-if test "${enable_mips_msa+set}" = set; then :
+if test ${enable_mips_msa+y}
+then :
   enableval=$enable_mips_msa; case "$enableval" in
       no|off)
          # disable the default enabling on __mips_msa systems:
 
-$as_echo "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no;;
+         enable_mips_msa=no ;;
       check)
 
-$as_echo "#define PNG_MIPS_MSA_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_CHECK_SUPPORTED /**/" >>confdefs.h
 ;;
       api)
 
-$as_echo "#define PNG_MIPS_MSA_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_MIPS_MSA_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-mmsa -mfp64'
             to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
+printf "%s\n" "$as_me: WARNING: --enable-mips-msa: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-mmsa -mfp64'
             to the compiler." >&2;};;
       *)
@@ -13646,13 +14522,13 @@
 fi
 
 
-# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
-# where MIPS optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'mips*')
+# Add MIPS-specific files to all builds where $host_cpu is mips ('mips*') or
+# where MIPS optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'mips*')
 
  if test "$enable_mips_msa" != 'no' &&
     case "$host_cpu" in
-      mipsel*|mips64el*) :;;
+      mipsel*|mips64el*) : ;;
     esac; then
   PNG_MIPS_MSA_TRUE=
   PNG_MIPS_MSA_FALSE='#'
@@ -13662,24 +14538,81 @@
 fi
 
 
+# MIPS
+# ===
+#
+# MIPS MMI (SIMD) support.
+
+# Check whether --enable-mips-mmi was given.
+if test ${enable_mips_mmi+y}
+then :
+  enableval=$enable_mips_mmi; case "$enableval" in
+      no|off)
+         # disable the default enabling on __mips_mmi systems:
+
+printf "%s\n" "#define PNG_MIPS_MMI_OPT 0" >>confdefs.h
+
+         # Prevent inclusion of the assembler files below:
+         enable_mips_mmi=no;;
+      check)
+
+printf "%s\n" "#define PNG_MIPS_MMI_CHECK_SUPPORTED /**/" >>confdefs.h
+;;
+      api)
+
+printf "%s\n" "#define PNG_MIPS_MMI_API_SUPPORTED /**/" >>confdefs.h
+;;
+      yes|on)
+
+printf "%s\n" "#define PNG_MIPS_MMI_OPT 1" >>confdefs.h
+
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-mips-mmi: please specify 'check' or 'api', if
+            you want the optimizations unconditionally pass '-mloongson-mmi -march=loongson3a'
+            to the compiler." >&5
+printf "%s\n" "$as_me: WARNING: --enable-mips-mmi: please specify 'check' or 'api', if
+            you want the optimizations unconditionally pass '-mloongson-mmi -march=loongson3a'
+            to the compiler." >&2;};;
+      *)
+         as_fn_error $? "--enable-mips-mmi=${enable_mips_mmi}: invalid value" "$LINENO" 5
+   esac
+fi
+
+
+# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
+# where MIPS optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'mips*')
+
+ if test "$enable_mips_mmi" != 'no' &&
+    case "$host_cpu" in
+      mipsel*|mips64el*) :;;
+    esac; then
+  PNG_MIPS_MMI_TRUE=
+  PNG_MIPS_MMI_FALSE='#'
+else
+  PNG_MIPS_MMI_TRUE='#'
+  PNG_MIPS_MMI_FALSE=
+fi
+
+
 # INTEL
 # =====
 #
 # INTEL SSE (SIMD) support.
 
 # Check whether --enable-intel-sse was given.
-if test "${enable_intel_sse+set}" = set; then :
+if test ${enable_intel_sse+y}
+then :
   enableval=$enable_intel_sse; case "$enableval" in
       no|off)
          # disable the default enabling:
 
-$as_echo "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 0" >>confdefs.h
 
          # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
+         enable_intel_sse=no ;;
       yes|on)
 
-$as_echo "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
+printf "%s\n" "#define PNG_INTEL_SSE_OPT 1" >>confdefs.h
 ;;
       *)
          as_fn_error $? "--enable-intel-sse=${enable_intel_sse}: invalid value" "$LINENO" 5
@@ -13687,13 +14620,13 @@
 fi
 
 
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
+# Add Intel-specific files to all builds where $host_cpu is Intel ('x86*') or
+# where Intel optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'x86*')
  if test "$enable_intel_sse" != 'no' &&
     case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
+      i?86|x86_64) : ;;
+      *)    test "$enable_intel_sse" != '' ;;
     esac; then
   PNG_INTEL_SSE_TRUE=
   PNG_INTEL_SSE_FALSE='#'
@@ -13704,55 +14637,56 @@
 
 
 # PowerPC
-# ===
+# =======
 #
 # PowerPC VSX (SIMD) support.
 
 # Check whether --enable-powerpc-vsx was given.
-if test "${enable_powerpc_vsx+set}" = set; then :
+if test ${enable_powerpc_vsx+y}
+then :
   enableval=$enable_powerpc_vsx; case "$enableval" in
       no|off)
          # disable the default enabling on __ppc64__ systems:
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 0" >>confdefs.h
 
-         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no;;
+         # Prevent inclusion of the platform-specific files below:
+         enable_powerpc_vsx=no ;;
       check)
 
-$as_echo "#define PNG_POWERPC_VSX_CHECK_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_CHECK_SUPPORTED /**/" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
             for the list of supported OSes." >&5
-$as_echo "$as_me: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
+printf "%s\n" "$as_me: WARNING: --enable-powerpc-vsx Please check contrib/powerpc/README file
             for the list of supported OSes." >&2;};;
       api)
 
-$as_echo "#define PNG_POWERPC_VSX_API_SUPPORTED /**/" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_API_SUPPORTED /**/" >>confdefs.h
 ;;
       yes|on)
 
-$as_echo "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
+printf "%s\n" "#define PNG_POWERPC_VSX_OPT 2" >>confdefs.h
 
-         { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
+         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-maltivec -mvsx'
-            or '-mcpu=power8'to the compiler." >&5
-$as_echo "$as_me: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
+            or '-mcpu=power8' to the compiler." >&5
+printf "%s\n" "$as_me: WARNING: --enable-powerpc-vsx: please specify 'check' or 'api', if
             you want the optimizations unconditionally pass '-maltivec -mvsx'
-            or '-mcpu=power8'to the compiler." >&2;};;
+            or '-mcpu=power8' to the compiler." >&2;};;
       *)
          as_fn_error $? "--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value" "$LINENO" 5
    esac
 fi
 
 
-# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'powerpc*')
+# Add PowerPC-specific files to all builds where $host_cpu is powerpc('powerpc*')
+# or where PowerPC optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'powerpc*')
 
  if test "$enable_powerpc_vsx" != 'no' &&
     case "$host_cpu" in
-      powerpc*|ppc64*) :;;
+      powerpc*|ppc64*) : ;;
     esac; then
   PNG_POWERPC_VSX_TRUE=
   PNG_POWERPC_VSX_FALSE='#'
@@ -13762,9 +14696,91 @@
 fi
 
 
+# LOONGARCH
+# ===
+#
+# LOONGARCH LSX (SIMD) support
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: Extra options for compiler: $PNG_COPTS" >&5
-$as_echo "$as_me: Extra options for compiler: $PNG_COPTS" >&6;}
+if test "$LSX_CFLAGS" = ''; then
+    LSX_CFLAGS="-mlsx"
+fi
+
+compiler_support_loongarch_lsx=no
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether to use loongarch LSX intrinsics" >&5
+printf %s "checking whether to use loongarch LSX intrinsics... " >&6; }
+save_CFLAGS=$CFLAGS
+CFLAGS="$CFLAGS $LSX_CFLAGS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include<lsxintrin.h>
+int main(){
+    __m128i a, b, c;
+    a = __lsx_vadd_w(b, c);
+    return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"
+then :
+  compiler_support_loongarch_lsx=yes
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
+CFLAGS=$save_CFLAGS
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $compiler_support_loongarch_lsx" >&5
+printf "%s\n" "$compiler_support_loongarch_lsx" >&6; }
+
+# Check whether --enable-loongarch-lsx was given.
+if test ${enable_loongarch_lsx+y}
+then :
+  enableval=$enable_loongarch_lsx; case "$enableval" in
+      no|off)
+         # disable the default enabling on __loongarch_simd systems:
+
+printf "%s\n" "#define PNG_LOONGARCH_LSX_OPT 0" >>confdefs.h
+
+         # Prevent inclusion of the assembler files below:
+         enable_loongarch_lsx=no;;
+      yes|on)
+
+printf "%s\n" "#define PNG_LOONGARCH_LSX_OPT 1" >>confdefs.h
+
+         ;;
+      *)
+         as_fn_error $? "--enable-loongarch-lsx=${enable_loongarch_lsx}: invalid value" "$LINENO" 5
+   esac
+fi
+
+
+if test "$enable_loongarch_lsx" != 'no'; then
+   if test $compiler_support_loongarch_lsx = yes; then
+
+printf "%s\n" "#define PNG_LOONGARCH_LSX_OPT 1" >>confdefs.h
+
+   else
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: Compiler does not support loongarch LSX." >&5
+printf "%s\n" "$as_me: WARNING: Compiler does not support loongarch LSX." >&2;}
+   fi
+fi
+
+# Add LOONGARCH specific files to all builds where the host_cpu is loongarch ('loongarch*') or
+# where LOONGARCH optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'loongarch*')
+
+ if test "$enable_loongarch_lsx" != 'no' && test $compiler_support_loongarch_lsx = yes &&
+    case "$host_cpu" in
+      loongarch*) :;;
+      *)    test "$enable_loongarch_lsx" != '';;
+    esac; then
+  PNG_LOONGARCH_LSX_TRUE=
+  PNG_LOONGARCH_LSX_FALSE='#'
+else
+  PNG_LOONGARCH_LSX_TRUE='#'
+  PNG_LOONGARCH_LSX_FALSE=
+fi
+
+
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: Extra options for compiler: $PNG_COPTS" >&5
+printf "%s\n" "$as_me: Extra options for compiler: $PNG_COPTS" >&6;}
 
 # Config files, substituting as above
 ac_config_files="$ac_config_files Makefile libpng.pc:libpng.pc.in"
@@ -13782,8 +14798,8 @@
 # config.status only pays attention to the cache file if you give it
 # the --recheck option to rerun configure.
 #
-# `ac_cv_env_foo' variables (set or unset) will be overridden when
-# loading this file, other *unset* `ac_cv_foo' will be assigned the
+# 'ac_cv_env_foo' variables (set or unset) will be overridden when
+# loading this file, other *unset* 'ac_cv_foo' will be assigned the
 # following values.
 
 _ACEOF
@@ -13799,8 +14815,8 @@
     case $ac_val in #(
     *${as_nl}*)
       case $ac_var in #(
-      *_cv_*) { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
-$as_echo "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
+      *_cv_*) { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: cache variable $ac_var contains a newline" >&5
+printf "%s\n" "$as_me: WARNING: cache variable $ac_var contains a newline" >&2;} ;;
       esac
       case $ac_var in #(
       _ | IFS | as_nl) ;; #(
@@ -13813,14 +14829,14 @@
   (set) 2>&1 |
     case $as_nl`(ac_space=' '; set) 2>&1` in #(
     *${as_nl}ac_space=\ *)
-      # `set' does not quote correctly, so add quotes: double-quote
+      # 'set' does not quote correctly, so add quotes: double-quote
       # substitution turns \\\\ into \\, and sed turns \\ into \.
       sed -n \
 	"s/'/'\\\\''/g;
 	  s/^\\([_$as_cr_alnum]*_cv_[_$as_cr_alnum]*\\)=\\(.*\\)/\\1='\\2'/p"
       ;; #(
     *)
-      # `set' quotes correctly as required by POSIX, so do not add quotes.
+      # 'set' quotes correctly as required by POSIX, so do not add quotes.
       sed -n "/^[_$as_cr_alnum]*_cv_[_$as_cr_alnum]*=/p"
       ;;
     esac |
@@ -13830,15 +14846,15 @@
      /^ac_cv_env_/b end
      t clear
      :clear
-     s/^\([^=]*\)=\(.*[{}].*\)$/test "${\1+set}" = set || &/
+     s/^\([^=]*\)=\(.*[{}].*\)$/test ${\1+y} || &/
      t end
      s/^\([^=]*\)=\(.*\)$/\1=${\1=\2}/
      :end' >>confcache
 if diff "$cache_file" confcache >/dev/null 2>&1; then :; else
   if test -w "$cache_file"; then
     if test "x$cache_file" != "x/dev/null"; then
-      { $as_echo "$as_me:${as_lineno-$LINENO}: updating cache $cache_file" >&5
-$as_echo "$as_me: updating cache $cache_file" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: updating cache $cache_file" >&5
+printf "%s\n" "$as_me: updating cache $cache_file" >&6;}
       if test ! -f "$cache_file" || test -h "$cache_file"; then
 	cat confcache >"$cache_file"
       else
@@ -13852,8 +14868,8 @@
       fi
     fi
   else
-    { $as_echo "$as_me:${as_lineno-$LINENO}: not updating unwritable cache $cache_file" >&5
-$as_echo "$as_me: not updating unwritable cache $cache_file" >&6;}
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: not updating unwritable cache $cache_file" >&5
+printf "%s\n" "$as_me: not updating unwritable cache $cache_file" >&6;}
   fi
 fi
 rm -f confcache
@@ -13870,7 +14886,7 @@
 for ac_i in : $LIBOBJS; do test "x$ac_i" = x: && continue
   # 1. Remove the extension, and $U if already installed.
   ac_script='s/\$U\././;s/\.o$//;s/\.obj$//'
-  ac_i=`$as_echo "$ac_i" | sed "$ac_script"`
+  ac_i=`printf "%s\n" "$ac_i" | sed "$ac_script"`
   # 2. Prepend LIBOBJDIR.  When used with automake>=1.10 LIBOBJDIR
   #    will be set to the directory where LIBOBJS objects are built.
   as_fn_append ac_libobjs " \${LIBOBJDIR}$ac_i\$U.$ac_objext"
@@ -13881,14 +14897,14 @@
 LTLIBOBJS=$ac_ltlibobjs
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking that generated files are newer than configure" >&5
-$as_echo_n "checking that generated files are newer than configure... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking that generated files are newer than configure" >&5
+printf %s "checking that generated files are newer than configure... " >&6; }
    if test -n "$am_sleep_pid"; then
      # Hide warnings about reused PIDs.
      wait $am_sleep_pid 2>/dev/null
    fi
-   { $as_echo "$as_me:${as_lineno-$LINENO}: result: done" >&5
-$as_echo "done" >&6; }
+   { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: done" >&5
+printf "%s\n" "done" >&6; }
  if test -n "$EXEEXT"; then
   am__EXEEXT_TRUE=
   am__EXEEXT_FALSE='#'
@@ -13913,6 +14929,14 @@
   as_fn_error $? "conditional \"am__fastdepCCAS\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${ENABLE_TESTS_TRUE}" && test -z "${ENABLE_TESTS_FALSE}"; then
+  as_fn_error $? "conditional \"ENABLE_TESTS\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
+if test -z "${ENABLE_TOOLS_TRUE}" && test -z "${ENABLE_TOOLS_FALSE}"; then
+  as_fn_error $? "conditional \"ENABLE_TOOLS\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${HAVE_CLOCK_GETTIME_TRUE}" && test -z "${HAVE_CLOCK_GETTIME_FALSE}"; then
   as_fn_error $? "conditional \"HAVE_CLOCK_GETTIME\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
@@ -13949,6 +14973,10 @@
   as_fn_error $? "conditional \"PNG_MIPS_MSA\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${PNG_MIPS_MMI_TRUE}" && test -z "${PNG_MIPS_MMI_FALSE}"; then
+  as_fn_error $? "conditional \"PNG_MIPS_MMI\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${PNG_INTEL_SSE_TRUE}" && test -z "${PNG_INTEL_SSE_FALSE}"; then
   as_fn_error $? "conditional \"PNG_INTEL_SSE\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
@@ -13957,13 +14985,17 @@
   as_fn_error $? "conditional \"PNG_POWERPC_VSX\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${PNG_LOONGARCH_LSX_TRUE}" && test -z "${PNG_LOONGARCH_LSX_FALSE}"; then
+  as_fn_error $? "conditional \"PNG_LOONGARCH_LSX\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 
 : "${CONFIG_STATUS=./config.status}"
 ac_write_fail=0
 ac_clean_files_save=$ac_clean_files
 ac_clean_files="$ac_clean_files $CONFIG_STATUS"
-{ $as_echo "$as_me:${as_lineno-$LINENO}: creating $CONFIG_STATUS" >&5
-$as_echo "$as_me: creating $CONFIG_STATUS" >&6;}
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating $CONFIG_STATUS" >&5
+printf "%s\n" "$as_me: creating $CONFIG_STATUS" >&6;}
 as_write_fail=0
 cat >$CONFIG_STATUS <<_ASEOF || as_write_fail=1
 #! $SHELL
@@ -13986,63 +15018,65 @@
 
 # Be more Bourne compatible
 DUALCASE=1; export DUALCASE # for MKS sh
-if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then :
+if test ${ZSH_VERSION+y} && (emulate sh) >/dev/null 2>&1
+then :
   emulate sh
   NULLCMD=:
   # Pre-4.2 versions of Zsh do word splitting on ${1+"$@"}, which
   # is contrary to our usage.  Disable this feature.
   alias -g '${1+"$@"}'='"$@"'
   setopt NO_GLOB_SUBST
-else
-  case `(set -o) 2>/dev/null` in #(
+else case e in #(
+  e) case `(set -o) 2>/dev/null` in #(
   *posix*) :
     set -o posix ;; #(
   *) :
      ;;
+esac ;;
 esac
 fi
 
 
+
+# Reset variables that may have inherited troublesome values from
+# the environment.
+
+# IFS needs to be set, to space, tab, and newline, in precisely that order.
+# (If _AS_PATH_WALK were called with IFS unset, it would have the
+# side effect of setting IFS to empty, thus disabling word splitting.)
+# Quoting is to prevent editors from complaining about space-tab.
 as_nl='
 '
 export as_nl
-# Printing a long string crashes Solaris 7 /usr/bin/printf.
-as_echo='\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo
-as_echo=$as_echo$as_echo$as_echo$as_echo$as_echo$as_echo
-# Prefer a ksh shell builtin over an external printf program on Solaris,
-# but without wasting forks for bash or zsh.
-if test -z "$BASH_VERSION$ZSH_VERSION" \
-    && (test "X`print -r -- $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='print -r --'
-  as_echo_n='print -rn --'
-elif (test "X`printf %s $as_echo`" = "X$as_echo") 2>/dev/null; then
-  as_echo='printf %s\n'
-  as_echo_n='printf %s'
-else
-  if test "X`(/usr/ucb/echo -n -n $as_echo) 2>/dev/null`" = "X-n $as_echo"; then
-    as_echo_body='eval /usr/ucb/echo -n "$1$as_nl"'
-    as_echo_n='/usr/ucb/echo -n'
-  else
-    as_echo_body='eval expr "X$1" : "X\\(.*\\)"'
-    as_echo_n_body='eval
-      arg=$1;
-      case $arg in #(
-      *"$as_nl"*)
-	expr "X$arg" : "X\\(.*\\)$as_nl";
-	arg=`expr "X$arg" : ".*$as_nl\\(.*\\)"`;;
-      esac;
-      expr "X$arg" : "X\\(.*\\)" | tr -d "$as_nl"
-    '
-    export as_echo_n_body
-    as_echo_n='sh -c $as_echo_n_body as_echo'
-  fi
-  export as_echo_body
-  as_echo='sh -c $as_echo_body as_echo'
-fi
+IFS=" ""	$as_nl"
+
+PS1='$ '
+PS2='> '
+PS4='+ '
+
+# Ensure predictable behavior from utilities with locale-dependent output.
+LC_ALL=C
+export LC_ALL
+LANGUAGE=C
+export LANGUAGE
+
+# We cannot yet rely on "unset" to work, but we need these variables
+# to be unset--not just set to an empty or harmless value--now, to
+# avoid bugs in old shells (e.g. pre-3.0 UWIN ksh).  This construct
+# also avoids known problems related to "unset" and subshell syntax
+# in other old shells (e.g. bash 2.01 and pdksh 5.2.14).
+for as_var in BASH_ENV ENV MAIL MAILPATH CDPATH
+do eval test \${$as_var+y} \
+  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
+done
+
+# Ensure that fds 0, 1, and 2 are open.
+if (exec 3>&0) 2>/dev/null; then :; else exec 0</dev/null; fi
+if (exec 3>&1) 2>/dev/null; then :; else exec 1>/dev/null; fi
+if (exec 3>&2)            ; then :; else exec 2>/dev/null; fi
 
 # The user is always right.
-if test "${PATH_SEPARATOR+set}" != set; then
+if ${PATH_SEPARATOR+false} :; then
   PATH_SEPARATOR=:
   (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 && {
     (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 ||
@@ -14051,13 +15085,6 @@
 fi
 
 
-# IFS
-# We need space, tab and new line, in precisely that order.  Quoting is
-# there to prevent editors from complaining about space-tab.
-# (If _AS_PATH_WALK were called with IFS unset, it would disable word
-# splitting by setting IFS to empty value.)
-IFS=" ""	$as_nl"
-
 # Find who we are.  Look in the path if we contain no directory separator.
 as_myself=
 case $0 in #((
@@ -14066,43 +15093,27 @@
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    test -r "$as_dir/$0" && as_myself=$as_dir/$0 && break
+  case $as_dir in #(((
+    '') as_dir=./ ;;
+    */) ;;
+    *) as_dir=$as_dir/ ;;
+  esac
+    test -r "$as_dir$0" && as_myself=$as_dir$0 && break
   done
 IFS=$as_save_IFS
 
      ;;
 esac
-# We did not find ourselves, most probably we were run as `sh COMMAND'
+# We did not find ourselves, most probably we were run as 'sh COMMAND'
 # in which case we are not to be found in the path.
 if test "x$as_myself" = x; then
   as_myself=$0
 fi
 if test ! -f "$as_myself"; then
-  $as_echo "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
+  printf "%s\n" "$as_myself: error: cannot find myself; rerun with an absolute file name" >&2
   exit 1
 fi
 
-# Unset variables that we do not need and which cause bugs (e.g. in
-# pre-3.0 UWIN ksh).  But do not cause bugs in bash 2.01; the "|| exit 1"
-# suppresses any "Segmentation fault" message there.  '((' could
-# trigger a bug in pdksh 5.2.14.
-for as_var in BASH_ENV ENV MAIL MAILPATH
-do eval test x\${$as_var+set} = xset \
-  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
-done
-PS1='$ '
-PS2='> '
-PS4='+ '
-
-# NLS nuisances.
-LC_ALL=C
-export LC_ALL
-LANGUAGE=C
-export LANGUAGE
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
 
 
 # as_fn_error STATUS ERROR [LINENO LOG_FD]
@@ -14115,9 +15126,9 @@
   as_status=$1; test $as_status -eq 0 && as_status=1
   if test "$4"; then
     as_lineno=${as_lineno-"$3"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
-    $as_echo "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
+    printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: $2" >&$4
   fi
-  $as_echo "$as_me: error: $2" >&2
+  printf "%s\n" "$as_me: error: $2" >&2
   as_fn_exit $as_status
 } # as_fn_error
 
@@ -14148,22 +15159,25 @@
   { eval $1=; unset $1;}
 }
 as_unset=as_fn_unset
+
 # as_fn_append VAR VALUE
 # ----------------------
 # Append the text in VALUE to the end of the definition contained in VAR. Take
 # advantage of any shell optimizations that allow amortized linear growth over
 # repeated appends, instead of the typical quadratic growth present in naive
 # implementations.
-if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null; then :
+if (eval "as_var=1; as_var+=2; test x\$as_var = x12") 2>/dev/null
+then :
   eval 'as_fn_append ()
   {
     eval $1+=\$2
   }'
-else
-  as_fn_append ()
+else case e in #(
+  e) as_fn_append ()
   {
     eval $1=\$$1\$2
-  }
+  } ;;
+esac
 fi # as_fn_append
 
 # as_fn_arith ARG...
@@ -14171,16 +15185,18 @@
 # Perform arithmetic evaluation on the ARGs, and store the result in the
 # global $as_val. Take advantage of shells that can avoid forks. The arguments
 # must be portable across $(()) and expr.
-if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null; then :
+if (eval "test \$(( 1 + 1 )) = 2") 2>/dev/null
+then :
   eval 'as_fn_arith ()
   {
     as_val=$(( $* ))
   }'
-else
-  as_fn_arith ()
+else case e in #(
+  e) as_fn_arith ()
   {
     as_val=`expr "$@" || test $? -eq 1`
-  }
+  } ;;
+esac
 fi # as_fn_arith
 
 
@@ -14207,7 +15223,7 @@
 $as_expr X/"$0" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$0" : 'X\(//\)$' \| \
 	 X"$0" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$0" |
+printf "%s\n" X/"$0" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -14229,6 +15245,10 @@
 as_cr_digits='0123456789'
 as_cr_alnum=$as_cr_Letters$as_cr_digits
 
+
+# Determine whether it's possible to make 'echo' print without a newline.
+# These variables are no longer used directly by Autoconf, but are AC_SUBSTed
+# for compatibility with existing Makefiles.
 ECHO_C= ECHO_N= ECHO_T=
 case `echo -n x` in #(((((
 -n*)
@@ -14242,6 +15262,12 @@
   ECHO_N='-n';;
 esac
 
+# For backward compatibility with old third-party macros, we provide
+# the shell variables $as_echo and $as_echo_n.  New code should use
+# AS_ECHO(["message"]) and AS_ECHO_N(["message"]), respectively.
+as_echo='printf %s\n'
+as_echo_n='printf %s'
+
 rm -f conf$$ conf$$.exe conf$$.file
 if test -d conf$$.dir; then
   rm -f conf$$.dir/conf$$.file
@@ -14253,9 +15279,9 @@
   if ln -s conf$$.file conf$$ 2>/dev/null; then
     as_ln_s='ln -s'
     # ... but there are two gotchas:
-    # 1) On MSYS, both `ln -s file dir' and `ln file dir' fail.
-    # 2) DJGPP < 2.04 has no symlinks; `ln -s' creates a wrapper executable.
-    # In both cases, we have to default to `cp -pR'.
+    # 1) On MSYS, both 'ln -s file dir' and 'ln file dir' fail.
+    # 2) DJGPP < 2.04 has no symlinks; 'ln -s' creates a wrapper executable.
+    # In both cases, we have to default to 'cp -pR'.
     ln -s conf$$.file conf$$.dir 2>/dev/null && test ! -f conf$$.exe ||
       as_ln_s='cp -pR'
   elif ln conf$$.file conf$$ 2>/dev/null; then
@@ -14283,7 +15309,7 @@
     as_dirs=
     while :; do
       case $as_dir in #(
-      *\'*) as_qdir=`$as_echo "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
+      *\'*) as_qdir=`printf "%s\n" "$as_dir" | sed "s/'/'\\\\\\\\''/g"`;; #'(
       *) as_qdir=$as_dir;;
       esac
       as_dirs="'$as_qdir' $as_dirs"
@@ -14292,7 +15318,7 @@
 	 X"$as_dir" : 'X\(//\)[^/]' \| \
 	 X"$as_dir" : 'X\(//\)$' \| \
 	 X"$as_dir" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$as_dir" |
+printf "%s\n" X"$as_dir" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -14336,10 +15362,12 @@
 as_executable_p=as_fn_executable_p
 
 # Sed expression to map a string onto a valid CPP name.
-as_tr_cpp="eval sed 'y%*$as_cr_letters%P$as_cr_LETTERS%;s%[^_$as_cr_alnum]%_%g'"
+as_sed_cpp="y%*$as_cr_letters%P$as_cr_LETTERS%;s%[^_$as_cr_alnum]%_%g"
+as_tr_cpp="eval sed '$as_sed_cpp'" # deprecated
 
 # Sed expression to map a string onto a valid variable name.
-as_tr_sh="eval sed 'y%*+%pp%;s%[^_$as_cr_alnum]%_%g'"
+as_sed_sh="y%*+%pp%;s%[^_$as_cr_alnum]%_%g"
+as_tr_sh="eval sed '$as_sed_sh'" # deprecated
 
 
 exec 6>&1
@@ -14354,8 +15382,8 @@
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by libpng $as_me 1.6.38.git, which was
-generated by GNU Autoconf 2.69.  Invocation command line was
+This file was extended by libpng $as_me 1.6.43.git, which was
+generated by GNU Autoconf 2.72.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
   CONFIG_HEADERS  = $CONFIG_HEADERS
@@ -14387,7 +15415,7 @@
 
 cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 ac_cs_usage="\
-\`$as_me' instantiates files and other configuration actions
+'$as_me' instantiates files and other configuration actions
 from templates according to the current configuration.  Unless the files
 and actions are specified as TAGs, all are instantiated by default.
 
@@ -14417,14 +15445,16 @@
 Report bugs to <png-mng-implement@lists.sourceforge.net>."
 
 _ACEOF
+ac_cs_config=`printf "%s\n" "$ac_configure_args" | sed "$ac_safe_unquote"`
+ac_cs_config_escaped=`printf "%s\n" "$ac_cs_config" | sed "s/^ //; s/'/'\\\\\\\\''/g"`
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
-ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
+ac_cs_config='$ac_cs_config_escaped'
 ac_cs_version="\\
-libpng config.status 1.6.38.git
-configured by $0, generated by GNU Autoconf 2.69,
+libpng config.status 1.6.43.git
+configured by $0, generated by GNU Autoconf 2.72,
   with options \\"\$ac_cs_config\\"
 
-Copyright (C) 2012 Free Software Foundation, Inc.
+Copyright (C) 2023 Free Software Foundation, Inc.
 This config.status script is free software; the Free Software Foundation
 gives unlimited permission to copy, distribute and modify it."
 
@@ -14464,15 +15494,15 @@
   -recheck | --recheck | --rechec | --reche | --rech | --rec | --re | --r)
     ac_cs_recheck=: ;;
   --version | --versio | --versi | --vers | --ver | --ve | --v | -V )
-    $as_echo "$ac_cs_version"; exit ;;
+    printf "%s\n" "$ac_cs_version"; exit ;;
   --config | --confi | --conf | --con | --co | --c )
-    $as_echo "$ac_cs_config"; exit ;;
+    printf "%s\n" "$ac_cs_config"; exit ;;
   --debug | --debu | --deb | --de | --d | -d )
     debug=: ;;
   --file | --fil | --fi | --f )
     $ac_shift
     case $ac_optarg in
-    *\'*) ac_optarg=`$as_echo "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_optarg=`printf "%s\n" "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
     '') as_fn_error $? "missing file argument" ;;
     esac
     as_fn_append CONFIG_FILES " '$ac_optarg'"
@@ -14480,23 +15510,23 @@
   --header | --heade | --head | --hea )
     $ac_shift
     case $ac_optarg in
-    *\'*) ac_optarg=`$as_echo "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
+    *\'*) ac_optarg=`printf "%s\n" "$ac_optarg" | sed "s/'/'\\\\\\\\''/g"` ;;
     esac
     as_fn_append CONFIG_HEADERS " '$ac_optarg'"
     ac_need_defaults=false;;
   --he | --h)
     # Conflict between --help and --header
-    as_fn_error $? "ambiguous option: \`$1'
-Try \`$0 --help' for more information.";;
+    as_fn_error $? "ambiguous option: '$1'
+Try '$0 --help' for more information.";;
   --help | --hel | -h )
-    $as_echo "$ac_cs_usage"; exit ;;
+    printf "%s\n" "$ac_cs_usage"; exit ;;
   -q | -quiet | --quiet | --quie | --qui | --qu | --q \
   | -silent | --silent | --silen | --sile | --sil | --si | --s)
     ac_cs_silent=: ;;
 
   # This is an error.
-  -*) as_fn_error $? "unrecognized option: \`$1'
-Try \`$0 --help' for more information." ;;
+  -*) as_fn_error $? "unrecognized option: '$1'
+Try '$0 --help' for more information." ;;
 
   *) as_fn_append ac_config_targets " $1"
      ac_need_defaults=false ;;
@@ -14517,7 +15547,7 @@
 if \$ac_cs_recheck; then
   set X $SHELL '$0' $ac_configure_args \$ac_configure_extra_args --no-create --no-recursion
   shift
-  \$as_echo "running CONFIG_SHELL=$SHELL \$*" >&6
+  \printf "%s\n" "running CONFIG_SHELL=$SHELL \$*" >&6
   CONFIG_SHELL='$SHELL'
   export CONFIG_SHELL
   exec "\$@"
@@ -14531,7 +15561,7 @@
   sed 'h;s/./-/g;s/^.../## /;s/...$/ ##/;p;x;p;x' <<_ASBOX
 ## Running $as_me. ##
 _ASBOX
-  $as_echo "$ac_log"
+  printf "%s\n" "$ac_log"
 } >&5
 
 _ACEOF
@@ -14586,12 +15616,14 @@
 lt_cv_to_tool_file_cmd='`$ECHO "$lt_cv_to_tool_file_cmd" | $SED "$delay_single_quote_subst"`'
 reload_flag='`$ECHO "$reload_flag" | $SED "$delay_single_quote_subst"`'
 reload_cmds='`$ECHO "$reload_cmds" | $SED "$delay_single_quote_subst"`'
+FILECMD='`$ECHO "$FILECMD" | $SED "$delay_single_quote_subst"`'
 deplibs_check_method='`$ECHO "$deplibs_check_method" | $SED "$delay_single_quote_subst"`'
 file_magic_cmd='`$ECHO "$file_magic_cmd" | $SED "$delay_single_quote_subst"`'
 file_magic_glob='`$ECHO "$file_magic_glob" | $SED "$delay_single_quote_subst"`'
 want_nocaseglob='`$ECHO "$want_nocaseglob" | $SED "$delay_single_quote_subst"`'
 sharedlib_from_linklib_cmd='`$ECHO "$sharedlib_from_linklib_cmd" | $SED "$delay_single_quote_subst"`'
 AR='`$ECHO "$AR" | $SED "$delay_single_quote_subst"`'
+lt_ar_flags='`$ECHO "$lt_ar_flags" | $SED "$delay_single_quote_subst"`'
 AR_FLAGS='`$ECHO "$AR_FLAGS" | $SED "$delay_single_quote_subst"`'
 archiver_list_spec='`$ECHO "$archiver_list_spec" | $SED "$delay_single_quote_subst"`'
 STRIP='`$ECHO "$STRIP" | $SED "$delay_single_quote_subst"`'
@@ -14715,13 +15747,13 @@
 lt_SP2NL \
 lt_NL2SP \
 reload_flag \
+FILECMD \
 deplibs_check_method \
 file_magic_cmd \
 file_magic_glob \
 want_nocaseglob \
 sharedlib_from_linklib_cmd \
 AR \
-AR_FLAGS \
 archiver_list_spec \
 STRIP \
 RANLIB \
@@ -14841,7 +15873,7 @@
     "libpng.pc") CONFIG_FILES="$CONFIG_FILES libpng.pc:libpng.pc.in" ;;
     "libpng-config") CONFIG_FILES="$CONFIG_FILES libpng-config:libpng-config.in" ;;
 
-  *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
+  *) as_fn_error $? "invalid argument: '$ac_config_target'" "$LINENO" 5;;
   esac
 done
 
@@ -14851,9 +15883,9 @@
 # We use the long form for the default assignment because of an extremely
 # bizarre bug on SunOS 4.1.3.
 if $ac_need_defaults; then
-  test "${CONFIG_FILES+set}" = set || CONFIG_FILES=$config_files
-  test "${CONFIG_HEADERS+set}" = set || CONFIG_HEADERS=$config_headers
-  test "${CONFIG_COMMANDS+set}" = set || CONFIG_COMMANDS=$config_commands
+  test ${CONFIG_FILES+y} || CONFIG_FILES=$config_files
+  test ${CONFIG_HEADERS+y} || CONFIG_HEADERS=$config_headers
+  test ${CONFIG_COMMANDS+y} || CONFIG_COMMANDS=$config_commands
 fi
 
 # Have a temporary directory for convenience.  Make it in the build tree
@@ -14861,7 +15893,7 @@
 # creating and moving files from /tmp can sometimes cause problems.
 # Hook for its removal unless debugging.
 # Note that there is a small window in which the directory will not be cleaned:
-# after its creation but before its name has been assigned to `$tmp'.
+# after its creation but before its name has been assigned to '$tmp'.
 $debug ||
 {
   tmp= ac_tmp=
@@ -14885,7 +15917,7 @@
 
 # Set up the scripts for CONFIG_FILES section.
 # No need to generate them if there are no CONFIG_FILES.
-# This happens for instance with `./config.status config.h'.
+# This happens for instance with './config.status config.h'.
 if test -n "$CONFIG_FILES"; then
 
 
@@ -15043,13 +16075,13 @@
 
 # Set up the scripts for CONFIG_HEADERS section.
 # No need to generate them if there are no CONFIG_HEADERS.
-# This happens for instance with `./config.status Makefile'.
+# This happens for instance with './config.status Makefile'.
 if test -n "$CONFIG_HEADERS"; then
 cat >"$ac_tmp/defines.awk" <<\_ACAWK ||
 BEGIN {
 _ACEOF
 
-# Transform confdefs.h into an awk script `defines.awk', embedded as
+# Transform confdefs.h into an awk script 'defines.awk', embedded as
 # here-document in config.status, that substitutes the proper values into
 # config.h.in to produce config.h.
 
@@ -15159,7 +16191,7 @@
   esac
   case $ac_mode$ac_tag in
   :[FHL]*:*);;
-  :L* | :C*:*) as_fn_error $? "invalid tag \`$ac_tag'" "$LINENO" 5;;
+  :L* | :C*:*) as_fn_error $? "invalid tag '$ac_tag'" "$LINENO" 5;;
   :[FH]-) ac_tag=-:-;;
   :[FH]*) ac_tag=$ac_tag:$ac_tag.in;;
   esac
@@ -15181,33 +16213,33 @@
       -) ac_f="$ac_tmp/stdin";;
       *) # Look for the file first in the build tree, then in the source tree
 	 # (if the path is not absolute).  The absolute path cannot be DOS-style,
-	 # because $ac_f cannot contain `:'.
+	 # because $ac_f cannot contain ':'.
 	 test -f "$ac_f" ||
 	   case $ac_f in
 	   [\\/$]*) false;;
 	   *) test -f "$srcdir/$ac_f" && ac_f="$srcdir/$ac_f";;
 	   esac ||
-	   as_fn_error 1 "cannot find input file: \`$ac_f'" "$LINENO" 5;;
+	   as_fn_error 1 "cannot find input file: '$ac_f'" "$LINENO" 5;;
       esac
-      case $ac_f in *\'*) ac_f=`$as_echo "$ac_f" | sed "s/'/'\\\\\\\\''/g"`;; esac
+      case $ac_f in *\'*) ac_f=`printf "%s\n" "$ac_f" | sed "s/'/'\\\\\\\\''/g"`;; esac
       as_fn_append ac_file_inputs " '$ac_f'"
     done
 
-    # Let's still pretend it is `configure' which instantiates (i.e., don't
+    # Let's still pretend it is 'configure' which instantiates (i.e., don't
     # use $as_me), people would be surprised to read:
     #    /* config.h.  Generated by config.status.  */
     configure_input='Generated from '`
-	  $as_echo "$*" | sed 's|^[^:]*/||;s|:[^:]*/|, |g'
+	  printf "%s\n" "$*" | sed 's|^[^:]*/||;s|:[^:]*/|, |g'
 	`' by configure.'
     if test x"$ac_file" != x-; then
       configure_input="$ac_file.  $configure_input"
-      { $as_echo "$as_me:${as_lineno-$LINENO}: creating $ac_file" >&5
-$as_echo "$as_me: creating $ac_file" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: creating $ac_file" >&5
+printf "%s\n" "$as_me: creating $ac_file" >&6;}
     fi
     # Neutralize special characters interpreted by sed in replacement strings.
     case $configure_input in #(
     *\&* | *\|* | *\\* )
-       ac_sed_conf_input=`$as_echo "$configure_input" |
+       ac_sed_conf_input=`printf "%s\n" "$configure_input" |
        sed 's/[\\\\&|]/\\\\&/g'`;; #(
     *) ac_sed_conf_input=$configure_input;;
     esac
@@ -15224,7 +16256,7 @@
 	 X"$ac_file" : 'X\(//\)[^/]' \| \
 	 X"$ac_file" : 'X\(//\)$' \| \
 	 X"$ac_file" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$ac_file" |
+printf "%s\n" X"$ac_file" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15248,9 +16280,9 @@
 case "$ac_dir" in
 .) ac_dir_suffix= ac_top_builddir_sub=. ac_top_build_prefix= ;;
 *)
-  ac_dir_suffix=/`$as_echo "$ac_dir" | sed 's|^\.[\\/]||'`
+  ac_dir_suffix=/`printf "%s\n" "$ac_dir" | sed 's|^\.[\\/]||'`
   # A ".." for each directory in $ac_dir_suffix.
-  ac_top_builddir_sub=`$as_echo "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
+  ac_top_builddir_sub=`printf "%s\n" "$ac_dir_suffix" | sed 's|/[^\\/]*|/..|g;s|/||'`
   case $ac_top_builddir_sub in
   "") ac_top_builddir_sub=. ac_top_build_prefix= ;;
   *)  ac_top_build_prefix=$ac_top_builddir_sub/ ;;
@@ -15312,8 +16344,8 @@
 case `eval "sed -n \"\$ac_sed_dataroot\" $ac_file_inputs"` in
 *datarootdir*) ac_datarootdir_seen=yes;;
 *@datadir@*|*@docdir@*|*@infodir@*|*@localedir@*|*@mandir@*)
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&5
-$as_echo "$as_me: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&5
+printf "%s\n" "$as_me: WARNING: $ac_file_inputs seems to ignore the --datarootdir setting" >&2;}
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
   ac_datarootdir_hack='
@@ -15326,7 +16358,7 @@
 esac
 _ACEOF
 
-# Neutralize VPATH when `$srcdir' = `.'.
+# Neutralize VPATH when '$srcdir' = '.'.
 # Shell code in configure.ac might set extrasub.
 # FIXME: do we really want to maintain this feature?
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
@@ -15357,9 +16389,9 @@
   { ac_out=`sed -n '/\${datarootdir}/p' "$ac_tmp/out"`; test -n "$ac_out"; } &&
   { ac_out=`sed -n '/^[	 ]*datarootdir[	 ]*:*=/p' \
       "$ac_tmp/out"`; test -z "$ac_out"; } &&
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file contains a reference to the variable \`datarootdir'
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: $ac_file contains a reference to the variable 'datarootdir'
 which seems to be undefined.  Please make sure it is defined" >&5
-$as_echo "$as_me: WARNING: $ac_file contains a reference to the variable \`datarootdir'
+printf "%s\n" "$as_me: WARNING: $ac_file contains a reference to the variable 'datarootdir'
 which seems to be undefined.  Please make sure it is defined" >&2;}
 
   rm -f "$ac_tmp/stdin"
@@ -15375,20 +16407,20 @@
   #
   if test x"$ac_file" != x-; then
     {
-      $as_echo "/* $configure_input  */" \
+      printf "%s\n" "/* $configure_input  */" >&1 \
       && eval '$AWK -f "$ac_tmp/defines.awk"' "$ac_file_inputs"
     } >"$ac_tmp/config.h" \
       || as_fn_error $? "could not create $ac_file" "$LINENO" 5
     if diff "$ac_file" "$ac_tmp/config.h" >/dev/null 2>&1; then
-      { $as_echo "$as_me:${as_lineno-$LINENO}: $ac_file is unchanged" >&5
-$as_echo "$as_me: $ac_file is unchanged" >&6;}
+      { printf "%s\n" "$as_me:${as_lineno-$LINENO}: $ac_file is unchanged" >&5
+printf "%s\n" "$as_me: $ac_file is unchanged" >&6;}
     else
       rm -f "$ac_file"
       mv "$ac_tmp/config.h" "$ac_file" \
 	|| as_fn_error $? "could not create $ac_file" "$LINENO" 5
     fi
   else
-    $as_echo "/* $configure_input  */" \
+    printf "%s\n" "/* $configure_input  */" >&1 \
       && eval '$AWK -f "$ac_tmp/defines.awk"' "$ac_file_inputs" \
       || as_fn_error $? "could not create -" "$LINENO" 5
   fi
@@ -15408,7 +16440,7 @@
 	 X"$_am_arg" : 'X\(//\)[^/]' \| \
 	 X"$_am_arg" : 'X\(//\)$' \| \
 	 X"$_am_arg" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$_am_arg" |
+printf "%s\n" X"$_am_arg" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15428,8 +16460,8 @@
 	  s/.*/./; q'`/stamp-h$_am_stamp_count
  ;;
 
-  :C)  { $as_echo "$as_me:${as_lineno-$LINENO}: executing $ac_file commands" >&5
-$as_echo "$as_me: executing $ac_file commands" >&6;}
+  :C)  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: executing $ac_file commands" >&5
+printf "%s\n" "$as_me: executing $ac_file commands" >&6;}
  ;;
   esac
 
@@ -15455,7 +16487,7 @@
   for am_mf
   do
     # Strip MF so we end up with the name of the file.
-    am_mf=`$as_echo "$am_mf" | sed -e 's/:.*$//'`
+    am_mf=`printf "%s\n" "$am_mf" | sed -e 's/:.*$//'`
     # Check whether this is an Automake generated Makefile which includes
     # dependency-tracking related rules and includes.
     # Grep'ing the whole file directly is not great: AIX grep has a line
@@ -15467,7 +16499,7 @@
 	 X"$am_mf" : 'X\(//\)[^/]' \| \
 	 X"$am_mf" : 'X\(//\)$' \| \
 	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$am_mf" |
+printf "%s\n" X"$am_mf" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -15489,7 +16521,7 @@
 $as_expr X/"$am_mf" : '.*/\([^/][^/]*\)/*$' \| \
 	 X"$am_mf" : 'X\(//\)$' \| \
 	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$am_mf" |
+printf "%s\n" X/"$am_mf" |
     sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
@@ -15514,13 +16546,15 @@
    (exit $ac_status); } || am_rc=$?
   done
   if test $am_rc -ne 0; then
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: error: in '$ac_pwd':" >&5
+printf "%s\n" "$as_me: error: in '$ac_pwd':" >&2;}
 as_fn_error $? "Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  Try re-running configure with the
+    for automatic dependency tracking.  If GNU make was not used, consider
+    re-running the configure script with MAKE=\"gmake\" (or whatever is
+    necessary).  You can also try re-running configure with the
     '--disable-dependency-tracking' option to at least be able to build
     the package (albeit without support for automatic dependency tracking).
-See \`config.log' for more details" "$LINENO" 5; }
+See 'config.log' for more details" "$LINENO" 5; }
   fi
   { am_dirpart=; unset am_dirpart;}
   { am_filepart=; unset am_filepart;}
@@ -15673,6 +16707,9 @@
 # convert \$build files to toolchain format.
 to_tool_file_cmd=$lt_cv_to_tool_file_cmd
 
+# A file(cmd) program that detects file types.
+FILECMD=$lt_FILECMD
+
 # Method to check whether dependent libraries are shared objects.
 deplibs_check_method=$lt_deplibs_check_method
 
@@ -15691,8 +16728,11 @@
 # The archiver.
 AR=$lt_AR
 
+# Flags to create an archive (by configure).
+lt_ar_flags=$lt_ar_flags
+
 # Flags to create an archive.
-AR_FLAGS=$lt_AR_FLAGS
+AR_FLAGS=\${ARFLAGS-"\$lt_ar_flags"}
 
 # How to feed a file listing to the archiver.
 archiver_list_spec=$lt_archiver_list_spec
@@ -16060,6 +17100,7 @@
   esac
 
 
+
 ltmain=$ac_aux_dir/ltmain.sh
 
 
@@ -16067,7 +17108,7 @@
   # if finds mixed CR/LF and LF-only lines.  Since sed operates in
   # text mode, it properly converts lines to CR/LF.  This bash problem
   # is reportedly fixed, but why not run on old versions too?
-  sed '$q' "$ltmain" >> "$cfgfile" \
+  $SED '$q' "$ltmain" >> "$cfgfile" \
      || (rm -f "$cfgfile"; exit 1)
 
    mv -f "$cfgfile" "$ofile" ||
@@ -16110,7 +17151,8 @@
   $ac_cs_success || as_fn_exit 1
 fi
 if test -n "$ac_unrecognized_opts" && test "$enable_option_checking" != no; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: unrecognized options: $ac_unrecognized_opts" >&5
-$as_echo "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2;}
+  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: WARNING: unrecognized options: $ac_unrecognized_opts" >&5
+printf "%s\n" "$as_me: WARNING: unrecognized options: $ac_unrecognized_opts" >&2;}
 fi
 
+
diff --git a/configure.ac b/configure.ac
index 17a6a2f..b9162e8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 # configure.ac
 
-# Copyright (c) 2018-2019 Cosmin Truta
+# Copyright (c) 2018-2024 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 
 # This code is released under the libpng license.
@@ -25,8 +25,8 @@
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.6.38.git],[png-mng-implement@lists.sourceforge.net])
-AC_CONFIG_MACRO_DIR([scripts])
+AC_INIT([libpng],[1.6.43.git],[png-mng-implement@lists.sourceforge.net])
+AC_CONFIG_MACRO_DIR([scripts/autoconf])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
 # color-tests requires automake 1.11 or later
@@ -46,10 +46,10 @@
 dnl AM_PREREQ([1.11.2])
 dnl stop configure from automagically running automake
 
-PNGLIB_VERSION=1.6.38.git
+PNGLIB_VERSION=1.6.43.git
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=38
+PNGLIB_RELEASE=43
 
 dnl End of version number stuff
 
@@ -89,9 +89,27 @@
 DFNCPP="$CPP"
 AC_SUBST(DFNCPP)
 
-# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
-# checks the compiler with a program that generates a warning), add the
-# following option to deal with this
+AC_ARG_ENABLE([tests],
+   AS_HELP_STRING([--disable-tests],
+      [do not build the test programs (default is to build)]),
+      [enable_tests="$enableval"],
+      [enable_tests=yes])
+
+AM_CONDITIONAL([ENABLE_TESTS],
+   [test "$enable_tests" != "no"])
+
+AC_ARG_ENABLE([tools],
+   AS_HELP_STRING([--disable-tools],
+      [do not build the auxiliary tools (default is to build)]),
+      [enable_tools="$enableval"],
+      [enable_tools=yes])
+
+AM_CONDITIONAL([ENABLE_TOOLS],
+   [test "$enable_tools" != "no"])
+
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail
+# (it checks the compiler with a program that generates a warning).
+# Add the following option to deal with this:
 AC_ARG_VAR(PNG_COPTS,
    [additional flags for the C compiler, use this for options that would]
    [cause configure itself to fail])
@@ -114,10 +132,10 @@
       CFLAGS="$sav_CFLAGS"
     fi],)
 
-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# This is incompatible with the new default mode, so we test for that and force the 
-# "-std=c89" compiler option:
+# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89.
+# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining
+# _POSIX_SOURCE to 1. This is incompatible with the new default mode, so
+# we test for that and force the "-std=c89" compiler option:
 AC_MSG_CHECKING([if we need to force back C standard to C89])
 AC_COMPILE_IFELSE(
    [AC_LANG_PROGRAM([
@@ -133,22 +151,17 @@
    CFLAGS="$CFLAGS -std=c89"
 ])
 
-# Checks for header files.
-AC_HEADER_STDC
-
-# Checks for typedefs, structures, and compiler characteristics.
-AC_C_CONST
-AC_TYPE_SIZE_T
+# Checks for structures and compiler characteristics.
 AC_STRUCT_TM
 AC_C_RESTRICT
 
 # Checks for library functions.
-AC_FUNC_STRTOD
-AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
+AC_CHECK_FUNCS([pow], ,
+  [AC_CHECK_LIB([m], [pow], , [AC_MSG_ERROR([cannot find pow])])])
 
-# Some later POSIX 1003.1 functions are required for test programs, failure here
-# is soft (the corresponding test program is not built).
-AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
+# Some later POSIX 1003.1 functions are required for test programs, failure
+# here is soft (the corresponding test program is not built).
+AC_CHECK_FUNC([clock_gettime], , [AC_MSG_WARN([not building timepng])])
 AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
 
 AC_ARG_WITH(zlib-prefix,
@@ -156,8 +169,9 @@
       [prefix that may have been used in installed zlib]),
       [ZPREFIX=${withval}],
       [ZPREFIX='z_'])
-AC_CHECK_LIB(z, zlibVersion, ,
-    AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
+AC_CHECK_LIB([z], [zlibVersion], ,
+  [AC_CHECK_LIB([z], [${ZPREFIX}zlibVersion], ,
+     [AC_MSG_ERROR([zlib not installed])])])
 
 # The following is for pngvalid, to ensure it catches FP errors even on
 # platforms that don't enable FP exceptions, the function appears in the math
@@ -296,7 +310,7 @@
 AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
    [test "$enable_unversioned_libpng_config" != "no"])
 
-# HOST SPECIFIC OPTIONS
+# HOST-SPECIFIC OPTIONS
 # =====================
 #
 # DEFAULT
@@ -314,24 +328,33 @@
          enable_mips_msa=no
          AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
            [Disable MIPS_MSA optimizations])
+         enable_mips_mmi=no
+         AC_DEFINE([PNG_MIPS_MMI_OPT], [0],
+           [Disable MIPS_MMI optimizations])
          enable_powerpc_vsx=no
          AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
            [Disable POWERPC VSX optimizations])
          enable_intel_sse=no
          AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
            [Disable INTEL_SSE optimizations])
+         enable_loongarch_lsx=no
+         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [0],
+           [Disable LOONGARCH_LSX optimizations])
          ;;
       *)
          # allow enabling hardware optimization on any system:
          case "$host_cpu" in
             arm*|aarch64*)
               enable_arm_neon=yes
-              AC_DEFINE([PNG_ARM_NEON_OPT], [0],
+              AC_DEFINE([PNG_ARM_NEON_OPT], [2],
                 [Enable ARM_NEON optimizations])
               ;;
             mipsel*|mips64el*)
+              enable_mips_mmi=yes
               enable_mips_msa=yes
-              AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
+              AC_DEFINE([PNG_MIPS_MMI_OPT], [1],
+                [Enable MIPS_MMI optimizations])
+              AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
                 [Enable MIPS_MSA optimizations])
               ;;
             i?86|x86_64)
@@ -344,6 +367,11 @@
               AC_DEFINE([PNG_POWERPC_VSX_OPT], [2],
                 [Enable POWERPC VSX optimizations])
               ;;
+            loongarch*)
+              enable_loongarch_lsx=yes
+              AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1],
+                [Enable LOONGARCH_LSX optimizations])
+              ;;
          esac
          ;;
    esac])
@@ -366,7 +394,7 @@
          AC_DEFINE([PNG_ARM_NEON_OPT], [0],
                    [Disable ARM Neon optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_arm_neon=no;;
+         enable_arm_neon=no ;;
       check)
          AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
                    [Check for ARM Neon support at run-time]);;
@@ -383,19 +411,19 @@
          AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
    esac])
 
-# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
-# where ARM optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'arm*')
+# Add ARM-specific files to all builds where $host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'arm*')
 
 AM_CONDITIONAL([PNG_ARM_NEON],
    [test "$enable_arm_neon" != 'no' &&
     case "$host_cpu" in
-      arm*|aarch64*) :;;
-      *)    test "$enable_arm_neon" != '';;
+      arm*|aarch64*) : ;;
+      *)    test "$enable_arm_neon" != '' ;;
     esac])
 
 # MIPS
-# ===
+# ====
 #
 # MIPS MSA (SIMD) support.
 
@@ -412,7 +440,7 @@
          AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
                    [Disable MIPS MSA optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no;;
+         enable_mips_msa=no ;;
       check)
          AC_DEFINE([PNG_MIPS_MSA_CHECK_SUPPORTED], [],
                    [Check for MIPS MSA support at run-time]);;
@@ -429,12 +457,57 @@
          AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}: invalid value])
    esac])
 
+# Add MIPS-specific files to all builds where $host_cpu is mips ('mips*') or
+# where MIPS optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'mips*')
+
+AM_CONDITIONAL([PNG_MIPS_MSA],
+   [test "$enable_mips_msa" != 'no' &&
+    case "$host_cpu" in
+      mipsel*|mips64el*) : ;;
+    esac])
+
+# MIPS
+# ===
+#
+# MIPS MMI (SIMD) support.
+
+AC_ARG_ENABLE([mips-mmi],
+   AS_HELP_STRING([[[--enable-mips-mmi]]],
+      [Enable MIPS MMI optimizations: =no/off, check, api, yes/on:]
+      [no/off: disable the optimizations; check: use internal checking code]
+      [(deprecated and poorly supported); api: disable by default, enable by]
+      [a call to png_set_option; yes/on: turn on unconditionally.]
+      [If not specified: determined by the compiler.]),
+   [case "$enableval" in
+      no|off)
+         # disable the default enabling on __mips_mmi systems:
+         AC_DEFINE([PNG_MIPS_MMI_OPT], [0],
+                   [Disable MIPS MMI optimizations])
+         # Prevent inclusion of the assembler files below:
+         enable_mips_mmi=no;;
+      check)
+         AC_DEFINE([PNG_MIPS_MMI_CHECK_SUPPORTED], [],
+                   [Check for MIPS MMI support at run-time]);;
+      api)
+         AC_DEFINE([PNG_MIPS_MMI_API_SUPPORTED], [],
+                   [Turn on MIPS MMI optimizations at run-time]);;
+      yes|on)
+         AC_DEFINE([PNG_MIPS_MMI_OPT], [1],
+                   [Enable MIPS MMI optimizations])
+         AC_MSG_WARN([--enable-mips-mmi: please specify 'check' or 'api', if]
+            [you want the optimizations unconditionally pass '-mloongson-mmi -march=loongson3a']
+            [to the compiler.]);;
+      *)
+         AC_MSG_ERROR([--enable-mips-mmi=${enable_mips_mmi}: invalid value])
+   esac])
+
 # Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
 # where MIPS optimizations were explicitly requested (this allows a fallback if a
 # future host CPU does not match 'mips*')
 
-AM_CONDITIONAL([PNG_MIPS_MSA],
-   [test "$enable_mips_msa" != 'no' &&
+AM_CONDITIONAL([PNG_MIPS_MMI],
+   [test "$enable_mips_mmi" != 'no' &&
     case "$host_cpu" in
       mipsel*|mips64el*) :;;
     esac])
@@ -456,7 +529,7 @@
          AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
                    [Disable Intel SSE optimizations])
          # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no;;
+         enable_intel_sse=no ;;
       yes|on)
          AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
                    [Enable Intel SSE optimizations]);;
@@ -464,18 +537,18 @@
          AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
    esac])
 
-# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# or where Intel optimizations were explicitly requested (this allows a
-# fallback if a future host CPU does not match 'x86*')
+# Add Intel-specific files to all builds where $host_cpu is Intel ('x86*') or
+# where Intel optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'x86*')
 AM_CONDITIONAL([PNG_INTEL_SSE],
    [test "$enable_intel_sse" != 'no' &&
     case "$host_cpu" in
-      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '';;
+      i?86|x86_64) : ;;
+      *)    test "$enable_intel_sse" != '' ;;
     esac])
 
 # PowerPC
-# ===
+# =======
 #
 # PowerPC VSX (SIMD) support.
 
@@ -491,8 +564,8 @@
          # disable the default enabling on __ppc64__ systems:
          AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
                    [Disable POWERPC VSX optimizations])
-         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no;;
+         # Prevent inclusion of the platform-specific files below:
+         enable_powerpc_vsx=no ;;
       check)
          AC_DEFINE([PNG_POWERPC_VSX_CHECK_SUPPORTED], [],
                    [Check for POWERPC VSX support at run-time])
@@ -506,21 +579,83 @@
                    [Enable POWERPC VSX optimizations])
          AC_MSG_WARN([--enable-powerpc-vsx: please specify 'check' or 'api', if]
             [you want the optimizations unconditionally pass '-maltivec -mvsx']
-            [or '-mcpu=power8'to the compiler.]);;
+            [or '-mcpu=power8' to the compiler.]);;
       *)
          AC_MSG_ERROR([--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value])
    esac])
 
-# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# future host CPU does not match 'powerpc*')
+# Add PowerPC-specific files to all builds where $host_cpu is powerpc('powerpc*')
+# or where PowerPC optimizations were explicitly requested (this allows a fallback
+# if a future host CPU does not match 'powerpc*')
 
 AM_CONDITIONAL([PNG_POWERPC_VSX],
    [test "$enable_powerpc_vsx" != 'no' &&
     case "$host_cpu" in
-      powerpc*|ppc64*) :;;
+      powerpc*|ppc64*) : ;;
     esac])
 
+# LOONGARCH
+# ===
+#
+# LOONGARCH LSX (SIMD) support
+
+if test "$LSX_CFLAGS" = ''; then
+    LSX_CFLAGS="-mlsx"
+fi
+
+compiler_support_loongarch_lsx=no
+AC_MSG_CHECKING(whether to use loongarch LSX intrinsics)
+save_CFLAGS=$CFLAGS
+CFLAGS="$CFLAGS $LSX_CFLAGS"
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
+#include<lsxintrin.h>
+int main(){
+    __m128i a, b, c;
+    a = __lsx_vadd_w(b, c);
+    return 0;
+}]])],compiler_support_loongarch_lsx=yes)
+CFLAGS=$save_CFLAGS
+AC_MSG_RESULT($compiler_support_loongarch_lsx)
+
+AC_ARG_ENABLE([loongarch-lsx],
+   AS_HELP_STRING([[[--enable-loongarch-lsx]]],
+      [Enable LOONGARCH LSX optimizations: =no/off, yes/on:]
+      [no/off: disable the optimizations;]
+      [yes/on: turn on unconditionally.]
+      [If not specified: determined by the compiler.]),
+   [case "$enableval" in
+      no|off)
+         # disable the default enabling on __loongarch_simd systems:
+         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [0],
+                   [Disable LOONGARCH LSX optimizations])
+         # Prevent inclusion of the assembler files below:
+         enable_loongarch_lsx=no;;
+      yes|on)
+         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1],
+                   [Enable LOONGARCH LSX optimizations])
+         ;;
+      *)
+         AC_MSG_ERROR([--enable-loongarch-lsx=${enable_loongarch_lsx}: invalid value])
+   esac])
+
+if test "$enable_loongarch_lsx" != 'no'; then
+   if test $compiler_support_loongarch_lsx = yes; then
+      AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1], [Enable LOONGARCH LSX optimizations])
+   else
+      AC_MSG_WARN([Compiler does not support loongarch LSX.])
+   fi
+fi
+
+# Add LOONGARCH specific files to all builds where the host_cpu is loongarch ('loongarch*') or
+# where LOONGARCH optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'loongarch*')
+
+AM_CONDITIONAL([PNG_LOONGARCH_LSX],
+   [test "$enable_loongarch_lsx" != 'no' && test $compiler_support_loongarch_lsx = yes &&
+    case "$host_cpu" in
+      loongarch*) :;;
+      *)    test "$enable_loongarch_lsx" != '';;
+    esac])
 
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
 
diff --git a/contrib/.editorconfig b/contrib/.editorconfig
new file mode 100644
index 0000000..bd9b590
--- /dev/null
+++ b/contrib/.editorconfig
@@ -0,0 +1,13 @@
+# https://editorconfig.org
+
+root = false
+
+[*]
+charset = unset
+end_of_line = unset
+indent_size = unset
+indent_style = unset
+insert_final_newline = unset
+max_doc_length = unset
+max_line_length = unset
+trim_trailing_whitespace = unset
diff --git a/contrib/arm-neon/android-ndk.c b/contrib/arm-neon/android-ndk.c
index fb3a489..c72c468 100644
--- a/contrib/arm-neon/android-ndk.c
+++ b/contrib/arm-neon/android-ndk.c
@@ -2,7 +2,6 @@
  *
  * Copyright (c) 2014 Glenn Randers-Pehrson
  * Written by John Bowler, 2014.
- * Last changed in libpng 1.6.10 [March 6, 2014]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -24,6 +23,7 @@
  * has been compiled only, not linked: no version of the library has been found,
  * only the header files exist in the NDK.
  */
+
 #include <cpu-features.h>
 
 static int
diff --git a/contrib/arm-neon/linux-auxv.c b/contrib/arm-neon/linux-auxv.c
index 4d26bd3..c5d7f51 100644
--- a/contrib/arm-neon/linux-auxv.c
+++ b/contrib/arm-neon/linux-auxv.c
@@ -2,7 +2,6 @@
  *
  * Copyright (c) 2014 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.10 [March 6, 2014]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -22,6 +21,7 @@
  * This generic __linux__ implementation requires reading /proc/self/auxv and
  * looking at each element for one that records NEON capabilities.
  */
+
 #include <unistd.h> /* for POSIX 1003.1 */
 #include <errno.h>  /* for EINTR */
 
diff --git a/contrib/arm-neon/linux.c b/contrib/arm-neon/linux.c
index a9bc360..b5429d0 100644
--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@@ -1,6 +1,5 @@
 /* contrib/arm-neon/linux.c
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
  * Copyright (c) 2014, 2017 Glenn Randers-Pehrson
  * Written by John Bowler, 2014, 2017.
  *
@@ -19,6 +18,7 @@
  * This code is strict ANSI-C and is probably moderately portable; it does
  * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
  */
+
 #include <stdio.h>
 
 static int
diff --git a/contrib/conftest/basic.dfa b/contrib/conftest/basic.dfa
new file mode 100644
index 0000000..f9ae5c3
--- /dev/null
+++ b/contrib/conftest/basic.dfa
@@ -0,0 +1,133 @@
+# basic.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2024
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with basic read and write support.  This enables the lowest
+# level libpng read and write APIs - the "row-by-row" ones.
+#
+# Support is enabled only for those transformations that are observed to be
+# required by widely used apps or are in the v3 specification.
+#
+
+everything = off
+
+# The sequential read code is enabled here; the progressive code can be used
+# instead but there is no point enabling both.
+
+option READ on
+option SEQUENTIAL_READ on
+option EASY_ACCESS on
+option SET_USER_LIMITS on
+option INFO_IMAGE on
+option READ_16BIT on
+
+# Errors: these can be disabled but then there won't be any error messages
+# just failures and the error messages are really needed for apps:
+option WARNINGS on
+option ERROR_TEXT on
+option BENIGN_READ_ERRORS on
+
+# Required for many display programs such as web browsers:
+option PROGRESSIVE_READ on
+
+# Switch on the write code - this makes a minimalist encoder but with
+# interlace support turned on; otherwise png_read_png..png_write_png will
+# fail on an interlaced image.
+option WRITE on
+option WRITE_INTERLACING on
+option WRITE_16BIT on
+
+# Usages of the 'fixed' APIs are relatively rare but they do occur
+# one or the other for both the API and the internal math.
+
+#Fixed point:
+option FIXED_POINT on
+
+#Floating point:
+option FLOATING_POINT on
+option FLOATING_ARITHMETIC on
+
+# Basic error handling, IO and user memory support.  The latter allows the
+# application program to provide its own implementations of 'malloc' and 'free'.
+option SETJMP on
+option STDIO on
+option USER_MEM on
+
+# Gamma handling: this needs to be on for the gamma handling
+option READ_GAMMA on
+
+# The supported chunks
+chunk bKGD on
+chunk cHRM on
+chunk eXIf on
+chunk gAMA on
+chunk iCCP on
+chunk iTXt on
+chunk pHYs on
+chunk sBIT on
+chunk sRGB on
+chunk tEXt on
+chunk tIME on
+chunk tRNS on
+chunk zTXt on
+
+# These don't seem to be used anywhere:
+# chunk pCAL
+# chunk sCAL
+# chunk sPLT
+
+# The rest of this is app dependent: none of these options are required for
+# read/write of the full range of PNG files and the normal chunk handling on
+# read.
+option WRITE_CUSTOMIZE_ZTXT_COMPRESSION on
+option WRITE_CUSTOMIZE_COMPRESSION on
+
+option READ_EXPAND on
+option READ_FILLER on
+option READ_GRAY_TO_RGB on
+option READ_INVERT on
+option READ_PACK on
+option READ_RGB_TO_GRAY on
+option READ_SCALE_16_TO_8 on
+option READ_SHIFT on
+option READ_STRIP_16_TO_8 on
+option READ_STRIP_ALPHA on
+option READ_SWAP on
+
+option CONVERT_tIME on
+
+# optipng
+option IO_STATE on
+option STORE_UNKNOWN_CHUNKS on
+option HANDLE_AS_UNKNOWN on
+
+# pngcrush
+option READ_USER_TRANSFORM on
+option WRITE_FLUSH on
+
+# pnmtopng
+chunk hIST on
+
+# cairo
+option WRITE_PACKSWAP on
+option WRITE_USER_TRANSFORM on
+
+# graphicsmagick
+option READ_USER_CHUNKS on
+
+# Qt5.15 qtgui (gentoo package split) Qt6.6 qtbase
+option READ_BGR on
+option WRITE_BGR on
+option READ_SWAP_ALPHA on
+option WRITE_SWAP_ALPHA on
+chunk oFFs on
+
+# ghostscript-gpl
+option WRITE_INVERT_ALPHA on
+option WRITE_INVERT on
diff --git a/contrib/examples/pngtopng.c b/contrib/examples/pngtopng.c
index 904b972..1d55496 100644
--- a/contrib/examples/pngtopng.c
+++ b/contrib/examples/pngtopng.c
@@ -5,8 +5,6 @@
  * related or neighboring rights to this work.  This work is published from:
  * United States.
  *
- * Last changed in libpng 1.6.29 [March 16, 2017]
- *
  * Read a PNG and write it out in a fixed format, using the 'simplified API'
  * that was introduced in libpng-1.6.0.
  *
diff --git a/contrib/libtests/gentests.sh b/contrib/libtests/gentests.sh
index f0f8d23..eba7ce5 100755
--- a/contrib/libtests/gentests.sh
+++ b/contrib/libtests/gentests.sh
@@ -2,8 +2,6 @@
 #
 # Copyright (c) 2013 John Cunningham Bowler
 #
-# Last changed in libpng 1.6.0 [February 14, 2013]
-#
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
diff --git a/contrib/libtests/makepng.c b/contrib/libtests/makepng.c
index 312062b..a866fc1 100644
--- a/contrib/libtests/makepng.c
+++ b/contrib/libtests/makepng.c
@@ -3,8 +3,6 @@
 /* Copyright: */
 #define COPYRIGHT "\251 2013,2015 John Cunningham Bowler"
 /*
- * Last changed in libpng 1.6.20 [November 24, 2015]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -299,25 +297,28 @@
             unsigned int x, y;
             volatile unsigned int ip = 0;
 
-            for (x=0; x<size; ++x) for (y=0; y<size; ++y)
+            for (x=0; x<size; ++x)
             {
-               ip = x + (size * y);
+               for (y=0; y<size; ++y)
+               {
+                  ip = x + (size * y);
 
-               /* size is at most 16, so the scaled value below fits in 16 bits
-                */
-#              define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
-#              define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
-                  (interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
-                  (size*size))
+                  /* size is at most 16, so the scaled value below fits in 16 bits
+                  */
+#                 define interp(pos, c1, c2) ((pos * c1) + ((size-pos) * c2))
+#                 define xyinterp(x, y, c1, c2, c3, c4) (((size * size / 2) +\
+                     (interp(x, c1, c2) * y + (size-y) * interp(x, c3, c4))) /\
+                     (size*size))
 
-               set_color(palette+ip, trans+ip,
-                  /* color:    green, red,blue,white */
-                  xyinterp(x, y,   0, 255,   0, 255),
-                  xyinterp(x, y, 255,   0,   0, 255),
-                  xyinterp(x, y,   0,   0, 255, 255),
-                  /* alpha:        0, 102, 204, 255) */
-                  xyinterp(x, y,   0, 102, 204, 255),
-                  gamma_table);
+                  set_color(palette+ip, trans+ip,
+                     /* color:    green, red,blue,white */
+                     xyinterp(x, y,   0, 255,   0, 255),
+                     xyinterp(x, y, 255,   0,   0, 255),
+                     xyinterp(x, y,   0,   0, 255, 255),
+                     /* alpha:        0, 102, 204, 255) */
+                     xyinterp(x, y,   0, 102, 204, 255),
+                     gamma_table);
+               }
             }
 
             return ip+1;
@@ -396,7 +397,7 @@
       image_size_of_type(color_type, bit_depth, colors, small)-1;
    png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
 
-   if (colors[0] == 0) if (small)
+   if (colors[0] == 0 && small)
    {
       unsigned int pixel_depth = pixel_depth_of_type(color_type, bit_depth);
 
@@ -495,7 +496,7 @@
          case 32:
          case 48:
          case 64:
-            /* The rows are filled by an alogorithm similar to the above, in the
+            /* The rows are filled by an algorithm similar to the above, in the
              * first row pixel bytes are all equal, increasing from 0 by 1 for
              * each pixel.  In the second row the bytes within a pixel are
              * incremented 1,3,5,7,... from the previous row byte.  Using an odd
@@ -858,10 +859,13 @@
       {
          unsigned int i;
 
-         if (real_gamma == 45455) for (i=0; i<256; ++i)
+         if (real_gamma == 45455)
          {
-            gamma_table[i] = (png_byte)i;
-            conv = 1.;
+            for (i=0; i<256; ++i)
+            {
+               gamma_table[i] = (png_byte)i;
+               conv = 1.;
+            }
          }
 
          else
@@ -1430,10 +1434,13 @@
    for (i=0; *param && i<nparams; ++i)
    {
       list[i] = param;
-      while (*++param) if (*param == '\n' || *param == ':')
+      while (*++param)
       {
-         *param++ = 0; /* Terminate last parameter */
-         break;        /* And start a new one. */
+         if (*param == '\n' || *param == ':')
+         {
+            *param++ = 0; /* Terminate last parameter */
+            break;        /* And start a new one. */
+         }
       }
    }
 
@@ -1869,7 +1876,7 @@
          }
    }
 
-   /* small and colors are incomparible (will probably crash if both are used at
+   /* small and colors are incompatible (will probably crash if both are used at
     * the same time!)
     */
    if (small && colors[0] != 0)
diff --git a/contrib/libtests/pngimage.c b/contrib/libtests/pngimage.c
index f130c04..be176b2 100644
--- a/contrib/libtests/pngimage.c
+++ b/contrib/libtests/pngimage.c
@@ -1,9 +1,9 @@
+
 /* pngimage.c
  *
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2015,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.24 [August 4, 2016]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -12,6 +12,7 @@
  * using png_read_png and then write with png_write_png.  Test all possible
  * transforms.
  */
+
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
@@ -317,11 +318,10 @@
 
    t &= -t; /* first set bit */
 
-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
-   {
-      if ((transform_info[i].transform & t) != 0)
-         return transform_info[i].name;
-   }
+   for (i=0; i<TTABLE_SIZE; ++i)
+      if (transform_info[i].name != NULL)
+         if ((transform_info[i].transform & t) != 0)
+            return transform_info[i].name;
 
    return "invalid transform";
 }
@@ -338,13 +338,16 @@
 {
    unsigned int i;
 
-   for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+   for (i=0; i<TTABLE_SIZE; ++i)
    {
-      if (transform_info[i].when & TRANSFORM_R)
-         read_transforms |= transform_info[i].transform;
+      if (transform_info[i].name != NULL)
+      {
+         if (transform_info[i].when & TRANSFORM_R)
+            read_transforms |= transform_info[i].transform;
 
-      if (transform_info[i].when & TRANSFORM_W)
-         write_transforms |= transform_info[i].transform;
+         if (transform_info[i].when & TRANSFORM_W)
+            write_transforms |= transform_info[i].transform;
+      }
    }
 
    /* Reversible transforms are those which are supported on both read and
@@ -962,21 +965,24 @@
       int bd = dp->bit_depth;
       unsigned int i;
 
-      for (i=0; i<TTABLE_SIZE; ++i) if (transform_info[i].name != NULL)
+      for (i=0; i<TTABLE_SIZE; ++i)
       {
-         int transform = transform_info[i].transform;
+         if (transform_info[i].name != NULL)
+         {
+            int transform = transform_info[i].transform;
 
-         if ((transform_info[i].valid_chunks == 0 ||
-               (transform_info[i].valid_chunks & chunks) != 0) &&
-            (transform_info[i].color_mask_required & ct) ==
-               transform_info[i].color_mask_required &&
-            (transform_info[i].color_mask_absent & ct) == 0 &&
-            (transform_info[i].bit_depths & bd) != 0 &&
-            (transform_info[i].when & TRANSFORM_R) != 0)
-            active |= transform;
+            if ((transform_info[i].valid_chunks == 0 ||
+                  (transform_info[i].valid_chunks & chunks) != 0) &&
+               (transform_info[i].color_mask_required & ct) ==
+                  transform_info[i].color_mask_required &&
+               (transform_info[i].color_mask_absent & ct) == 0 &&
+               (transform_info[i].bit_depths & bd) != 0 &&
+               (transform_info[i].when & TRANSFORM_R) != 0)
+               active |= transform;
 
-         else if ((transform_info[i].when & TRANSFORM_R) != 0)
-            inactive |= transform;
+            else if ((transform_info[i].when & TRANSFORM_R) != 0)
+               inactive |= transform;
+         }
       }
 
       /* Some transforms appear multiple times in the table; the 'active' status
@@ -1000,8 +1006,9 @@
    int interlace_method, compression_method, filter_method;
    const char *e = NULL;
 
-   png_get_IHDR(dp->read_pp, dp->read_ip, &width, &height, &bit_depth,
-      &color_type, &interlace_method, &compression_method, &filter_method);
+   if (!png_get_IHDR(dp->read_pp, dp->read_ip, &width, &height, &bit_depth,
+      &color_type, &interlace_method, &compression_method, &filter_method))
+      display_log(dp, LIBPNG_BUG, "png_get_IHDR failed");
 
 #  define C(item) if (item != dp->item) \
       display_log(dp, APP_WARNING, "IHDR " #item "(%lu) changed to %lu",\
@@ -1081,8 +1088,9 @@
                size_t x;
 
                /* Find the first error */
-               for (x=0; x<rowbytes-1; ++x) if (row[x] != orig[x])
-                  break;
+               for (x=0; x<rowbytes-1; ++x)
+                  if (row[x] != orig[x])
+                     break;
 
                display_log(dp, APP_FAIL,
                   "byte(%lu,%lu) changed 0x%.2x -> 0x%.2x",
@@ -1137,6 +1145,7 @@
                display_log(dp, LIBPNG_ERROR, "invalid colour type %d",
                   color_type);
                /*NOTREACHED*/
+               memset(sig_bits, 0, sizeof(sig_bits));
                bpp = 0;
                break;
          }
@@ -1198,7 +1207,7 @@
                sig_bits[0] = (png_byte)b;
                break;
 
-            case 4: /* Relicate twice */
+            case 4: /* Replicate twice */
                /* Value is 1, 2, 3 or 4 */
                b = 0xf & ((0xf << 4) >> sig_bits[0]);
                b |= b << 4;
@@ -1686,8 +1695,9 @@
 
                printf("%s: pngimage ", pass ? "PASS" : "FAIL");
 
-               for (j=1; j<option_end; ++j) if (j != ilog)
-                  printf("%s ", argv[j]);
+               for (j=1; j<option_end; ++j)
+                  if (j != ilog)
+                     printf("%s ", argv[j]);
 
                printf("%s\n", d.filename);
             }
diff --git a/contrib/libtests/pngstest.c b/contrib/libtests/pngstest.c
index a368bf0..973e60f 100644
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -1,7 +1,7 @@
-/*-
- * pngstest.c
+
+/* pngstest.c
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2013-2017 John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -10,8 +10,9 @@
  *
  * Test for the PNG 'simplified' APIs.
  */
+
 #define _ISOC90_SOURCE 1
-#define MALLOC_CHECK_ 2/*glibc facility: turn on debugging*/
+#define MALLOC_CHECK_ 2 /*glibc facility: turn on debugging*/
 
 #include <stddef.h>
 #include <stdlib.h>
@@ -1150,7 +1151,7 @@
  *
  * 2) Remove color by mapping to grayscale.  (Grayscale to color is a no-op.)
  *
- * 3) Convert between 8-bit and 16-bit components.  (Both directtions are
+ * 3) Convert between 8-bit and 16-bit components.  (Both directions are
  *    relevant.)
  *
  * This gives the following base format conversion matrix:
@@ -2701,7 +2702,7 @@
             {
                if ((a->opts & ACCUMULATE) == 0)
                {
-                  char pindex[9];
+                  char pindex[16];
                   sprintf(pindex, "%lu[%lu]", (unsigned long)y,
                      (unsigned long)a->image.colormap_entries);
                   logerror(a, a->file_name, ": bad pixel index: ", pindex);
@@ -2712,12 +2713,12 @@
             else if (y >= b->image.colormap_entries)
             {
                if ((b->opts & ACCUMULATE) == 0)
-                  {
-                  char pindex[9];
+               {
+                  char pindex[16];
                   sprintf(pindex, "%lu[%lu]", (unsigned long)y,
                      (unsigned long)b->image.colormap_entries);
                   logerror(b, b->file_name, ": bad pixel index: ", pindex);
-                  }
+               }
                result = 0;
             }
 
@@ -2820,8 +2821,11 @@
          bchannels = component_loc(bloc, formatb);
 
          /* Hence the btoa array. */
-         for (i=0; i<4; ++i) if (bloc[i] < 4)
-            btoa[bloc[i]] = aloc[i]; /* may be '4' for alpha */
+         for (i=0; i<4; ++i)
+         {
+            if (bloc[i] < 4)
+               btoa[bloc[i]] = aloc[i]; /* may be '4' for alpha */
+         }
 
          if (alpha_added)
             alpha_added = bloc[0]; /* location of alpha channel in image b */
@@ -3209,10 +3213,10 @@
    else if (image->opts & USE_FILE)
    {
 #ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
-      static int counter = 0;
+      static unsigned int counter = 0;
       char name[32];
 
-      sprintf(name, "%s%d.png", tmpf, ++counter);
+      sprintf(name, "%s%u.png", tmpf, ++counter);
 
       if (png_image_write_to_file(&image->image, name, convert_to_8bit,
          image->buffer+16, (png_int_32)image->stride, image->colormap))
diff --git a/contrib/libtests/pngunknown.c b/contrib/libtests/pngunknown.c
index 05bdd83..dfa9d10 100644
--- a/contrib/libtests/pngunknown.c
+++ b/contrib/libtests/pngunknown.c
@@ -1,7 +1,7 @@
 
 /* pngunknown.c - test the read side unknown chunk handling
  *
- * Last changed in libpng 1.6.32 [August 24, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2015,2017 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
@@ -370,7 +370,9 @@
 {
    int i = NINFO;
 
-   while (--i >= 0) if (chunk_info[i].flag == flag) return i;
+   while (--i >= 0)
+      if (chunk_info[i].flag == flag)
+         return i;
 
    fprintf(stderr, "pngunknown: internal error\n");
    exit(4);
@@ -547,27 +549,30 @@
 
       case PNG_HANDLE_CHUNK_AS_DEFAULT:
       case PNG_HANDLE_CHUNK_NEVER:
-         discard = 1/*handled; discard*/;
+         discard = 1; /*handled; discard*/
          break;
 
       case PNG_HANDLE_CHUNK_IF_SAFE:
       case PNG_HANDLE_CHUNK_ALWAYS:
-         discard = 0/*not handled; keep*/;
+         discard = 0; /*not handled; keep*/
          break;
    }
 
    /* Also store information about this chunk in the display, the relevant flag
     * is set if the chunk is to be kept ('not handled'.)
     */
-   if (chunk >= 0) if (!discard) /* stupidity to stop a GCC warning */
+   if (chunk >= 0)
    {
-      png_uint_32 flag = chunk_info[chunk].flag;
+      if (!discard) /* stupidity to stop a GCC warning */
+      {
+         png_uint_32 flag = chunk_info[chunk].flag;
 
-      if (pc->location & PNG_AFTER_IDAT)
-         d->after_IDAT |= flag;
+         if (pc->location & PNG_AFTER_IDAT)
+            d->after_IDAT |= flag;
 
-      else
-         d->before_IDAT |= flag;
+         else
+            d->before_IDAT |= flag;
+      }
    }
 
    /* However if there is no support to store unknown chunks don't ask libpng to
@@ -841,8 +846,9 @@
             {
                png_uint_32 y;
 
-               for (y=0; y<height; ++y) if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
-                  png_read_row(d->png_ptr, NULL, NULL);
+               for (y=0; y<height; ++y)
+                  if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
+                     png_read_row(d->png_ptr, NULL, NULL);
             }
          }
       } /* interlaced */
@@ -1091,15 +1097,15 @@
 
 static const char *standard_tests[] =
 {
- "discard", "default=discard", 0,
- "save", "default=save", 0,
- "if-safe", "default=if-safe", 0,
- "vpAg", "vpAg=if-safe", 0,
- "sTER", "sTER=if-safe", 0,
- "IDAT", "default=discard", "IDAT=save", 0,
- "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
-   "sBIT=save", "sRGB=save", "eXIf=save", 0,
- 0/*end*/
+   "discard", "default=discard", NULL,
+   "save", "default=save", NULL,
+   "if-safe", "default=if-safe", NULL,
+   "vpAg", "vpAg=if-safe", NULL,
+   "sTER", "sTER=if-safe", NULL,
+   "IDAT", "default=discard", "IDAT=save", NULL,
+   "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
+      "sBIT=save", "sRGB=save", "eXIf=save", NULL,
+   NULL /*end*/
 };
 
 static PNG_NORETURN void
@@ -1115,7 +1121,7 @@
 main(int argc, const char **argv)
 {
    FILE *fp;
-   png_uint_32 default_flags[4/*valid,unknown{before,after}*/];
+   png_uint_32 default_flags[4]; /*valid,unknown{before,after}*/
    int strict = 0, default_tests = 0;
    const char *count_argv = "default=save";
    const char *touch_file = NULL;
@@ -1153,8 +1159,9 @@
    /* GCC BUG: if (default_tests && argc != 1) triggers some weird GCC argc
     * optimization which causes warnings with -Wstrict-overflow!
     */
-   else if (default_tests) if (argc != 1)
-      usage(d.program, "extra arguments");
+   else if (default_tests)
+      if (argc != 1)
+         usage(d.program, "extra arguments");
 
    /* The name of the test file is the last argument; remove it. */
    d.file = argv[--argc];
@@ -1216,7 +1223,11 @@
          const char *result;
          int arg_count = 0;
 
-         while (*next) ++next, ++arg_count;
+         while (*next != NULL)
+         {
+            ++next;
+            ++arg_count;
+         }
 
          perform_one_test_safe(fp, arg_count, test, default_flags, &d,
             this_test);
diff --git a/contrib/libtests/pngvalid.c b/contrib/libtests/pngvalid.c
index d800110..3d66154 100644
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
@@ -1,7 +1,7 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2014-2017 John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -22,6 +22,7 @@
 #define _ISOC99_SOURCE 1 /* For floating point */
 #define _GNU_SOURCE 1 /* For the floating point exception extension */
 #define _BSD_SOURCE 1 /* For the floating point exception extension */
+#define _DEFAULT_SOURCE 1 /* For the floating point exception extension */
 
 #include <signal.h>
 #include <stdio.h>
@@ -69,9 +70,12 @@
 #endif
 
 /* pngvalid requires write support and one of the fixed or floating point APIs.
+ * progressive read is also required currently as the progressive read pointer
+ * is used to record the 'display' structure.
  */
-#if defined(PNG_WRITE_SUPPORTED) &&\
-   (defined(PNG_FIXED_POINT_SUPPORTED) || defined(PNG_FLOATING_POINT_SUPPORTED))
+#if defined PNG_WRITE_SUPPORTED &&\
+   (defined PNG_PROGRESSIVE_READ_SUPPORTED) &&\
+   (defined PNG_FIXED_POINT_SUPPORTED || defined PNG_FLOATING_POINT_SUPPORTED)
 
 #if PNG_LIBPNG_VER < 10500
 /* This deliberately lacks the const. */
@@ -5822,8 +5826,9 @@
       for (interlace_type = PNG_INTERLACE_NONE;
            interlace_type < INTERLACE_LAST; ++interlace_type)
       {
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            interlace_type, 0, 0, 0), do_read_interlace, pm->use_update_info);
+         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+            0/*palette*/, interlace_type, 0, 0, 0), do_read_interlace,
+            pm->use_update_info);
 
          if (fail(pm))
             return 0;
@@ -5876,47 +5881,50 @@
    {
       png_uint_32 h, w;
 
-      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])
+      for (h=1; h<=16; h+=hinc[bdlo])
       {
-         /* First test all the 'size' images against the sequential
-          * reader using libpng to deinterlace (where required.)  This
-          * validates the write side of libpng.  There are four possibilities
-          * to validate.
-          */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,
-            pm->use_update_info);
+         for (w=1; w<=16; w+=winc[bdlo])
+         {
+            /* First test all the 'size' images against the sequential
+            * reader using libpng to deinterlace (where required.)  This
+            * validates the write side of libpng.  There are four possibilities
+            * to validate.
+            */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 0), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,
-            pm->use_update_info);
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 1), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-         /* Now validate the interlaced read side - do_interlace true,
-          * in the progressive case this does actually make a difference
-          * to the code used in the non-interlaced case too.
-          */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,
-            pm->use_update_info);
+            /* Now validate the interlaced read side - do_interlace true,
+            * in the progressive case this does actually make a difference
+            * to the code used in the non-interlaced case too.
+            */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_NONE, w, h, 0), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
+            if (fail(pm))
+               return 0;
 
-#     if CAN_WRITE_INTERLACE
-         /* Validate the pngvalid code itself: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 1), 1/*do_interlace*/,
-            pm->use_update_info);
+#        if CAN_WRITE_INTERLACE
+            /* Validate the pngvalid code itself: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 1), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
+            if (fail(pm))
+               return 0;
+#        endif
+         }
       }
    }
 
@@ -5927,45 +5935,48 @@
    {
       png_uint_32 h, w;
 
-      for (h=1; h<=16; h+=hinc[bdlo]) for (w=1; w<=16; w+=winc[bdlo])
+      for (h=1; h<=16; h+=hinc[bdlo])
       {
-#     ifdef PNG_READ_INTERLACING_SUPPORTED
-         /* Test with pngvalid generated interlaced images first; we have
-          * already verify these are ok (unless pngvalid has self-consistent
-          * read/write errors, which is unlikely), so this detects errors in the
-          * read side first:
-          */
-#     if CAN_WRITE_INTERLACE
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,
-            pm->use_update_info);
+         for (w=1; w<=16; w+=winc[bdlo])
+         {
+#        ifdef PNG_READ_INTERLACING_SUPPORTED
+            /* Test with pngvalid generated interlaced images first; we have
+            * already verify these are ok (unless pngvalid has self-consistent
+            * read/write errors, which is unlikely), so this detects errors in
+            * the read side first:
+            */
+#        if CAN_WRITE_INTERLACE
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 1), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
-#     endif /* READ_INTERLACING */
+            if (fail(pm))
+               return 0;
+#        endif
+#        endif /* READ_INTERLACING */
 
-#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
-         /* Test the libpng write side against the pngvalid read side: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
-            pm->use_update_info);
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            /* Test the libpng write side against the pngvalid read side: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
+            if (fail(pm))
+               return 0;
+#        endif
 
-#     ifdef PNG_READ_INTERLACING_SUPPORTED
-#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
-         /* Test both together: */
-         standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
-            PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
-            pm->use_update_info);
+#        ifdef PNG_READ_INTERLACING_SUPPORTED
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            /* Test both together: */
+            standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo),
+               0/*palette*/, PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
+               pm->use_update_info);
 
-         if (fail(pm))
-            return 0;
-#     endif
-#     endif /* READ_INTERLACING */
+            if (fail(pm))
+               return 0;
+#        endif
+#        endif /* READ_INTERLACING */
+         }
       }
    }
 
@@ -6711,7 +6722,7 @@
    unsigned int out, png_byte sample_depth, double err, double limit,
    const char *name, double digitization_error)
 {
-   /* Compare the scaled, digitzed, values of our local calculation (in+-err)
+   /* Compare the scaled, digitized, values of our local calculation (in+-err)
     * with the digitized values libpng produced;  'sample_depth' is the actual
     * digitization depth of the libpng output colors (the bit depth except for
     * palette images where it is always 8.)  The check on 'err' is to detect
@@ -7635,7 +7646,7 @@
 
    else
    {
-      /* The default (built in) coeffcients, as above: */
+      /* The default (built in) coefficients, as above: */
 #     if PNG_LIBPNG_VER < 10700
          data.red_coefficient = 6968 / 32768.;
          data.green_coefficient = 23434 / 32768.;
@@ -9057,7 +9068,7 @@
 static int
 image_transform_test_counter(png_uint_32 counter, unsigned int max)
 {
-   /* Test the list to see if there is any point contining, given a current
+   /* Test the list to see if there is any point continuing, given a current
     * counter and a 'max' value.
     */
    image_transform *next = image_transform_first;
@@ -10001,9 +10012,12 @@
                case ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN:
                case ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED:
 #           endif /* ALPHA_MODE_SUPPORTED */
+#           if (defined PNG_READ_BACKGROUND_SUPPORTED) ||\
+               (defined PNG_READ_ALPHA_MODE_SUPPORTED)
                do_compose = (alpha > 0 && alpha < 1);
                use_input = (alpha != 0);
                break;
+#           endif
 
             default:
                break;
@@ -10649,16 +10663,21 @@
    {
       unsigned int i, j;
 
-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
-         if (i != j)
+      for (i=0; i<pm->ngamma_tests; ++i)
+      {
+         for (j=0; j<pm->ngamma_tests; ++j)
          {
-            gamma_transform_test(pm, colour_type, bit_depth, palette_number,
-               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j], 0/*sBIT*/,
-               pm->use_input_precision, 0 /*do not scale16*/);
+            if (i != j)
+            {
+               gamma_transform_test(pm, colour_type, bit_depth, palette_number,
+                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+                  0/*sBIT*/, pm->use_input_precision, 0/*do not scale16*/);
 
-            if (fail(pm))
-               return;
+               if (fail(pm))
+                  return;
+            }
          }
+      }
    }
 }
 
@@ -10687,14 +10706,17 @@
          {
             unsigned int j;
 
-            for (j=0; j<pm->ngamma_tests; ++j) if (i != j)
+            for (j=0; j<pm->ngamma_tests; ++j)
             {
-               gamma_transform_test(pm, colour_type, bit_depth, npalette,
-                  pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
-                  sbit, pm->use_input_precision_sbit, 0 /*scale16*/);
+               if (i != j)
+               {
+                  gamma_transform_test(pm, colour_type, bit_depth, npalette,
+                     pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+                     sbit, pm->use_input_precision_sbit, 0 /*scale16*/);
 
-               if (fail(pm))
-                  return;
+                  if (fail(pm))
+                     return;
+               }
             }
          }
       }
@@ -10946,14 +10968,17 @@
       unsigned int i, j;
 
       /* Don't skip the i==j case here - it's relevant. */
-      for (i=0; i<pm->ngamma_tests; ++i) for (j=0; j<pm->ngamma_tests; ++j)
+      for (i=0; i<pm->ngamma_tests; ++i)
       {
-         gamma_composition_test(pm, colour_type, bit_depth, palette_number,
-            pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
-            pm->use_input_precision, do_background, expand_16);
+         for (j=0; j<pm->ngamma_tests; ++j)
+         {
+            gamma_composition_test(pm, colour_type, bit_depth, palette_number,
+               pm->interlace_type, 1/pm->gammas[i], pm->gammas[j],
+               pm->use_input_precision, do_background, expand_16);
 
-         if (fail(pm))
-            return;
+            if (fail(pm))
+               return;
+         }
       }
    }
 }
@@ -11056,7 +11081,7 @@
          pm->calculations_use_input_precision = 0;
 
       if (summary)
-         summarize_gamma_errors(pm, 0/*who*/, 1/*low bit depth*/, 1/*indexed*/);
+         summarize_gamma_errors(pm, NULL/*who*/, 1/*low bit depth*/, 1/*indexed*/);
 
       if (fail(pm))
          return;
@@ -11182,8 +11207,10 @@
 {
    int x, y;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
-      return y;
+   for (y=0; y<8; ++y)
+      for (x=0; x<8; ++x)
+         if (adam7[y][x] == pass)
+            return y;
    return 0xf;
 }
 
@@ -11192,8 +11219,10 @@
 {
    int x, y;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
-      return x;
+   for (x=0; x<8; ++x)
+      for (y=0; y<8; ++y)
+         if (adam7[y][x] == pass)
+            return x;
    return 0xf;
 }
 
@@ -11202,18 +11231,24 @@
 {
    int x, y, base=(-1), inc=8;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   for (y=0; y<8; ++y)
    {
-      if (base == (-1))
-         base = y;
-      else if (base == y)
-         {}
-      else if (inc == y-base)
-         base=y;
-      else if (inc == 8)
-         inc = y-base, base=y;
-      else if (inc != y-base)
-         return 0xff; /* error - more than one 'inc' value! */
+      for (x=0; x<8; ++x)
+      {
+         if (adam7[y][x] == pass)
+         {
+            if (base == (-1))
+               base = y;
+            else if (base == y)
+               {}
+            else if (inc == y-base)
+               base=y;
+            else if (inc == 8)
+               inc = y-base, base=y;
+            else if (inc != y-base)
+               return 0xff; /* error - more than one 'inc' value! */
+         }
+      }
    }
 
    if (base == (-1)) return 0xfe; /* error - no row in pass! */
@@ -11236,18 +11271,24 @@
 {
    int x, y, base=(-1), inc=8;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   for (x=0; x<8; ++x)
    {
-      if (base == (-1))
-         base = x;
-      else if (base == x)
-         {}
-      else if (inc == x-base)
-         base=x;
-      else if (inc == 8)
-         inc = x-base, base=x;
-      else if (inc != x-base)
-         return 0xff; /* error - more than one 'inc' value! */
+      for (y=0; y<8; ++y)
+      {
+         if (adam7[y][x] == pass)
+         {
+            if (base == (-1))
+               base = x;
+            else if (base == x)
+               {}
+            else if (inc == x-base)
+               base=x;
+            else if (inc == 8)
+               inc = x-base, base=x;
+            else if (inc != x-base)
+               return 0xff; /* error - more than one 'inc' value! */
+         }
+      }
    }
 
    if (base == (-1)) return 0xfe; /* error - no row in pass! */
@@ -11311,8 +11352,9 @@
    int x;
    y &= 7;
    ++pass;
-   for (x=0; x<8; ++x) if (adam7[y][x] == pass)
-      return 1;
+   for (x=0; x<8; ++x)
+      if (adam7[y][x] == pass)
+         return 1;
 
    return 0;
 }
@@ -11324,8 +11366,9 @@
    int y;
    x &= 7;
    ++pass;
-   for (y=0; y<8; ++y) if (adam7[y][x] == pass)
-      return 1;
+   for (y=0; y<8; ++y)
+      if (adam7[y][x] == pass)
+         return 1;
 
    return 0;
 }
@@ -11339,11 +11382,17 @@
 
    height &= 7;
    ++pass;
-   for (y=0; y<8; ++y) for (x=0; x<8; ++x) if (adam7[y][x] == pass)
+   for (y=0; y<8; ++y)
    {
-      rows += tiles;
-      if (y < height) ++rows;
-      break; /* i.e. break the 'x', column, loop. */
+      for (x=0; x<8; ++x)
+      {
+         if (adam7[y][x] == pass)
+         {
+            rows += tiles;
+            if (y < height) ++rows;
+            break; /* i.e. break the 'x', column, loop. */
+         }
+      }
    }
 
    return rows;
@@ -11358,11 +11407,17 @@
 
    width &= 7;
    ++pass;
-   for (x=0; x<8; ++x) for (y=0; y<8; ++y) if (adam7[y][x] == pass)
+   for (x=0; x<8; ++x)
    {
-      cols += tiles;
-      if (x < width) ++cols;
-      break; /* i.e. break the 'y', row, loop. */
+      for (y=0; y<8; ++y)
+      {
+         if (adam7[y][x] == pass)
+         {
+            cols += tiles;
+            if (x < width) ++cols;
+            break; /* i.e. break the 'y', row, loop. */
+         }
+      }
    }
 
    return cols;
@@ -11719,7 +11774,7 @@
 
    /* The following allows results to pass if they correspond to anything in the
     * transformed range [input-.5,input+.5]; this is is required because of the
-    * way libpng treates the 16_TO_8 flag when building the gamma tables in
+    * way libpng treats the 16_TO_8 flag when building the gamma tables in
     * releases up to 1.6.0.
     *
     * TODO: review this
@@ -11810,21 +11865,21 @@
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
       else if (strncmp(*argv, "--transform-disable=",
          sizeof "--transform-disable") == 0)
-         {
+      {
          pm.test_transform = 1;
          transform_disable(*argv + sizeof "--transform-disable");
-         }
+      }
 
       else if (strncmp(*argv, "--transform-enable=",
          sizeof "--transform-enable") == 0)
-         {
+      {
          pm.test_transform = 1;
          transform_enable(*argv + sizeof "--transform-enable");
-         }
+      }
 #endif /* PNG_READ_TRANSFORMS_SUPPORTED */
 
       else if (strcmp(*argv, "--gamma") == 0)
-         {
+      {
          /* Just do two gamma tests here (2.2 and linear) for speed: */
          pm.ngamma_tests = 2U;
          pm.test_gamma_threshold = 1;
@@ -11833,7 +11888,7 @@
          pm.test_gamma_scale16 = 1;
          pm.test_gamma_background = 1; /* composition */
          pm.test_gamma_alpha_mode = 1;
-         }
+      }
 
       else if (strcmp(*argv, "--nogamma") == 0)
          pm.ngamma_tests = 0;
@@ -11875,7 +11930,14 @@
          pm.test_gamma_alpha_mode = 0;
 
       else if (strcmp(*argv, "--expand16") == 0)
-         pm.test_gamma_expand16 = 1;
+      {
+#        ifdef PNG_READ_EXPAND_16_SUPPORTED
+            pm.test_gamma_expand16 = 1;
+#        else
+            fprintf(stderr, "pngvalid: --expand16: no read support\n");
+            return SKIP;
+#        endif
+      }
 
       else if (strcmp(*argv, "--noexpand16") == 0)
          pm.test_gamma_expand16 = 0;
@@ -11890,10 +11952,15 @@
             pm.test_lbg_gamma_transform = pm.test_lbg_gamma_sbit =
             pm.test_lbg_gamma_composition = 0;
 
-#     ifdef PNG_WRITE_tRNS_SUPPORTED
-         else if (strcmp(*argv, "--tRNS") == 0)
+      else if (strcmp(*argv, "--tRNS") == 0)
+      {
+#        ifdef PNG_WRITE_tRNS_SUPPORTED
             pm.test_tRNS = 1;
-#     endif
+#        else
+            fprintf(stderr, "pngvalid: --tRNS: no write support\n");
+            return SKIP;
+#        endif
+      }
 
       else if (strcmp(*argv, "--notRNS") == 0)
          pm.test_tRNS = 0;
diff --git a/contrib/libtests/readpng.c b/contrib/libtests/readpng.c
index 60a2d46..7528e90 100644
--- a/contrib/libtests/readpng.c
+++ b/contrib/libtests/readpng.c
@@ -1,9 +1,8 @@
+
 /* readpng.c
  *
  * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.1 [March 28, 2013]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
diff --git a/contrib/libtests/tarith.c b/contrib/libtests/tarith.c
index c03f05a..e35b7ab 100644
--- a/contrib/libtests/tarith.c
+++ b/contrib/libtests/tarith.c
@@ -1,10 +1,9 @@
 
 /* tarith.c
  *
+ * Copyright (c) 2021 Cosmin Truta
  * Copyright (c) 2011-2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [February 14, 2013]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -88,6 +87,7 @@
    int    minorarith = 0;
 
    while (--argc > 0)
+   {
       if (strcmp(*++argv, "-a") == 0)
          showall = 1;
       else if (strcmp(*argv, "-e") == 0 && argc > 0)
@@ -105,6 +105,7 @@
          fprintf(stderr, "unknown argument %s\n", *argv);
          return 1;
       }
+   }
 
    do
    {
@@ -130,8 +131,8 @@
        */
       if (buffer[precision+7] != 71)
       {
-         fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n", test,
-            precision, buffer, (unsigned long)strlen(buffer));
+         fprintf(stderr, "%g[%d] -> '%s'[%lu] buffer overflow\n",
+            test, precision, buffer, (unsigned long)strlen(buffer));
          failed = 1;
       }
 
@@ -146,16 +147,16 @@
          if (test >= 0 && strcmp(buffer, "inf") ||
              test <  0 && strcmp(buffer, "-inf"))
          {
-            fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n", test,
-               precision, buffer);
+            fprintf(stderr, "%g[%d] -> '%s' but expected 'inf'\n",
+               test, precision, buffer);
             failed = 1;
          }
       }
       else if (!png_check_fp_number(buffer, precision+10, &state, &index) ||
           buffer[index] != 0)
       {
-         fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n", test,
-         precision, buffer, buffer[index]);
+         fprintf(stderr, "%g[%d] -> '%s' but has bad format ('%c')\n",
+            test, precision, buffer, buffer[index]);
          failed = 1;
       }
       else if (PNG_FP_IS_NEGATIVE(state) && !(test < 0))
@@ -187,7 +188,7 @@
          /* Check the result against the original. */
          double out = atof(buffer);
          double change = fabs((out - test)/test);
-         double allow = .5/pow(10,
+         double allow = .5 / pow(10,
             (precision >= DBL_DIG) ? DBL_DIG-1 : precision-1);
 
          /* NOTE: if you hit this error case are you compiling with gcc
@@ -257,8 +258,9 @@
    }
    while (--count);
 
-   printf("Tested %d finite values, %d non-finite, %d OK (%d failed) %d minor "
-      "arithmetic errors\n", finite, nonfinite, ok, failcount, minorarith);
+   printf("Tested %d finite values, %d non-finite, %d OK (%d failed) "
+      "%d minor arithmetic errors\n",
+      finite, nonfinite, ok, failcount, minorarith);
    printf(" Error with >=%d digit precision %.2f%%\n", DBL_DIG, max_abs);
    printf(" Error with < %d digit precision %.2f%%\n", DBL_DIG, max);
 
@@ -371,8 +373,8 @@
    /* This should never fail (it's a serious bug if it does): */
    if (index != 0 && index != 1)
    {
-      fprintf(stderr, "%s: read beyond end of string (%lu)\n", co->number,
-         (unsigned long)index);
+      fprintf(stderr, "%s: read beyond end of string (%lu)\n",
+         co->number, (unsigned long)index);
       return 0;
    }
 
@@ -503,8 +505,8 @@
       if (number_is_valid != c.number_was_valid)
       {
          fprintf(stderr,
-            "%s: character '%c' [0x%.2x] changed number validity\n", co->number,
-            ch, ch);
+            "%s: character '%c' [0x%.2x] changed number validity\n",
+            co->number, ch, ch);
          return 0;
       }
 
@@ -521,10 +523,13 @@
 {
    int ch;
 
-   if (c.cnumber+4 < sizeof co->number) for (ch=0; ch<256; ++ch)
+   if (c.cnumber+4 < sizeof co->number)
    {
-      if (!check_one_character(co, c, ch))
-         return 0;
+      for (ch=0; ch<256; ++ch)
+      {
+         if (!check_one_character(co, c, ch))
+            return 0;
+      }
    }
 
    return 1;
@@ -539,10 +544,13 @@
 
    if (c.cnumber+4 < sizeof co->number && c.limit >= 0)
    {
-      if (c.limit > 0) for (i=0; tests[i]; ++i)
+      if (c.limit > 0)
       {
-         if (!check_one_character(co, c, tests[i]))
-               return 0;
+         for (i=0; tests[i]; ++i)
+         {
+            if (!check_one_character(co, c, tests[i]))
+                  return 0;
+         }
       }
 
       /* At the end check all the characters. */
@@ -616,10 +624,10 @@
    png_int_32 times, div;
 
    while (--argc > 0)
-      {
-         fprintf(stderr, "unknown argument %s\n", *++argv);
-         return 1;
-      }
+   {
+      fprintf(stderr, "unknown argument %s\n", *++argv);
+      return 1;
+   }
 
    /* Find out about the random number generator. */
    randbuffer = RAND_MAX;
@@ -687,25 +695,25 @@
         ok = 0, ++overflow, fpround = fp/*misleading*/;
 
       if (verbose)
-         fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n", a, times, div,
-            fp, ok ? "ok" : "overflow");
+         fprintf(stderr, "TEST %d * %d / %d -> %lld (%s)\n",
+            a, times, div, fp, ok ? "ok" : "overflow");
 
       ++tested;
       if (png_muldiv(&result, a, times, div) != ok)
       {
          ++error;
          if (ok)
-             fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n", a,
-                times, div, fp);
+             fprintf(stderr, "%d * %d / %d -> overflow (expected %lld)\n",
+                a, times, div, fp);
          else
-             fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n", a,
-                times, div, result, fp);
+             fprintf(stderr, "%d * %d / %d -> %d (expected overflow %lld)\n",
+                a, times, div, result, fp);
       }
       else if (ok && result != fpround)
       {
          ++error;
-         fprintf(stderr, "%d * %d / %d -> %d not %lld\n", a, times, div, result,
-            fp);
+         fprintf(stderr, "%d * %d / %d -> %d not %lld\n",
+            a, times, div, result, fp);
       }
       else
          ++passed;
@@ -721,8 +729,8 @@
    }
    while (--count > 0);
 
-   printf("%d tests including %d overflows, %d passed, %d failed (%d 64-bit "
-      "errors)\n", tested, overflow, passed, error, error64);
+   printf("%d tests including %d overflows, %d passed, %d failed "
+      "(%d 64-bit errors)\n", tested, overflow, passed, error, error64);
    return 0;
 }
 
@@ -821,8 +829,9 @@
          {
             if (error > .68) /* By experiment error is less than .68 */
             {
-               fprintf(stderr, "16-bit log error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_log16bit(i), correct, error);
+               fprintf(stderr,
+                  "16-bit log error: %d: got %u, expected %f error: %f\n",
+                  i, png_log16bit(i), correct, error);
             }
          }
       }
@@ -841,8 +850,9 @@
             maxerr = fabs(error);
          if (fabs(error) > 1883) /* By experiment. */
          {
-            fprintf(stderr, "32-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp(i), correct, error);
+            fprintf(stderr,
+               "32-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp(i), correct, error);
          }
       }
 
@@ -859,8 +869,9 @@
             maxerr = fabs(error);
          if (fabs(error) > .50002) /* By experiment */
          {
-            fprintf(stderr, "8-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp8bit(i), correct, error);
+            fprintf(stderr,
+               "8-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp8bit(i), correct, error);
          }
       }
 
@@ -877,8 +888,9 @@
             maxerr = fabs(error);
          if (fabs(error) > .524) /* By experiment */
          {
-            fprintf(stderr, "16-bit exp error: %d: got %u, expected %f"
-                  " error: %f\n", i, png_exp16bit(i), correct, error);
+            fprintf(stderr,
+               "16-bit exp error: %d: got %u, expected %f error: %f\n",
+               i, png_exp16bit(i), correct, error);
          }
       }
 
@@ -940,7 +952,7 @@
 
 /**************************** VALIDATION TESTS ********************************/
 /* Various validation routines are included herein, they require some
- * definition for png_warning and png_error, seetings of VALIDATION:
+ * definition for png_warning and png_error, settings of VALIDATION:
  *
  * 1: validates the ASCII to floating point conversions
  * 2: validates png_muldiv
diff --git a/contrib/libtests/timepng.c b/contrib/libtests/timepng.c
index 23d8b17..0093a45 100644
--- a/contrib/libtests/timepng.c
+++ b/contrib/libtests/timepng.c
@@ -1,9 +1,8 @@
+
 /* timepng.c
  *
  * Copyright (c) 2013,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.22 [May 26, 2016]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -528,7 +527,7 @@
       }
    }
 
-   else if (nfiles == 0) /* Read from stdin withoout --dissemble */
+   else if (nfiles == 0) /* Read from stdin without --dissemble */
    {
       char filename[FILENAME_MAX+1];
 
diff --git a/contrib/mips-mmi/linux.c b/contrib/mips-mmi/linux.c
new file mode 100644
index 0000000..31525fd
--- /dev/null
+++ b/contrib/mips-mmi/linux.c
@@ -0,0 +1,142 @@
+
+/* contrib/mips-mmi/linux.c
+ *
+ * Copyright (c) 2024 Cosmin Truta
+ * Written by guxiwei, 2023
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/auxv.h>
+
+/*
+ * parse_r var, r - Helper assembler macro for parsing register names.
+ *
+ * This converts the register name in $n form provided in \r to the
+ * corresponding register number, which is assigned to the variable \var. It is
+ * needed to allow explicit encoding of instructions in inline assembly where
+ * registers are chosen by the compiler in $n form, allowing us to avoid using
+ * fixed register numbers.
+ *
+ * It also allows newer instructions (not implemented by the assembler) to be
+ * transparently implemented using assembler macros, instead of needing separate
+ * cases depending on toolchain support.
+ *
+ * Simple usage example:
+ * __asm__ __volatile__("parse_r __rt, %0\n\t"
+ *                      ".insn\n\t"
+ *                      "# di    %0\n\t"
+ *                      ".word   (0x41606000 | (__rt << 16))"
+ *                      : "=r" (status);
+ */
+
+/* Match an individual register number and assign to \var */
+#define _IFC_REG(n)                                \
+        ".ifc        \\r, $" #n "\n\t"             \
+        "\\var        = " #n "\n\t"                \
+        ".endif\n\t"
+
+__asm__(".macro        parse_r var r\n\t"
+        "\\var        = -1\n\t"
+        _IFC_REG(0)  _IFC_REG(1)  _IFC_REG(2)  _IFC_REG(3)
+        _IFC_REG(4)  _IFC_REG(5)  _IFC_REG(6)  _IFC_REG(7)
+        _IFC_REG(8)  _IFC_REG(9)  _IFC_REG(10) _IFC_REG(11)
+        _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15)
+        _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19)
+        _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23)
+        _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27)
+        _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31)
+        ".iflt        \\var\n\t"
+        ".error        \"Unable to parse register name \\r\"\n\t"
+        ".endif\n\t"
+        ".endm");
+
+#define HWCAP_LOONGSON_CPUCFG (1 << 14)
+
+static int cpucfg_available(void)
+{
+    return getauxval(AT_HWCAP) & HWCAP_LOONGSON_CPUCFG;
+}
+
+static int strstart(const char *str, const char *pfx, const char **ptr)
+{
+    while (*pfx && *pfx == *str) {
+        pfx++;
+        str++;
+    }
+    if (!*pfx && ptr)
+        *ptr = str;
+    return !*pfx;
+}
+
+/* Most toolchains have no CPUCFG support yet */
+static uint32_t read_cpucfg(uint32_t reg)
+{
+        uint32_t __res;
+
+        __asm__ __volatile__(
+                "parse_r __res,%0\n\t"
+                "parse_r reg,%1\n\t"
+                ".insn \n\t"
+                ".word (0xc8080118 | (reg << 21) | (__res << 11))\n\t"
+                :"=r"(__res)
+                :"r"(reg)
+                :
+                );
+        return __res;
+}
+
+#define LOONGSON_CFG1 0x1
+
+#define LOONGSON_CFG1_MMI    (1 << 4)
+
+static int cpu_flags_cpucfg(void)
+{
+    int flags = 0;
+    uint32_t cfg1 = read_cpucfg(LOONGSON_CFG1);
+
+    if (cfg1 & LOONGSON_CFG1_MMI)
+        flags = 1;
+
+    return flags;
+}
+
+static int cpu_flags_cpuinfo(void)
+{
+    FILE *f = fopen("/proc/cpuinfo", "r");
+    char buf[200];
+    int flags = 0;
+
+    if (!f)
+        return flags;
+
+    while (fgets(buf, sizeof(buf), f)) {
+        /* Legacy kernel may not export MMI in ASEs implemented */
+        if (strstart(buf, "cpu model", NULL)) {
+            if (strstr(buf, "Loongson-3 "))
+                flags = 1;
+            break;
+        }
+        if (strstart(buf, "ASEs implemented", NULL)) {
+            if (strstr(buf, " loongson-mmi"))
+                flags = 1;
+            break;
+        }
+    }
+    fclose(f);
+    return flags;
+}
+
+static int png_have_mmi()
+{
+    if (cpucfg_available())
+        return cpu_flags_cpucfg();
+    else
+        return cpu_flags_cpuinfo();
+    return 0;
+}
diff --git a/contrib/mips-msa/linux.c b/contrib/mips-msa/linux.c
index 140215c..cae8ca5 100644
--- a/contrib/mips-msa/linux.c
+++ b/contrib/mips-msa/linux.c
@@ -1,64 +1,55 @@
+
 /* contrib/mips-msa/linux.c
  *
+ * Copyright (c) 2020-2023 Cosmin Truta
  * Copyright (c) 2016 Glenn Randers-Pehrson
  * Written by Mandar Sahastrabuddhe, 2016.
- * Last changed in libpng 1.6.25beta03 [August 29, 2016]
+ * Updated by Sui Jingfeng, 2021.
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  *
- * SEE contrib/mips-msa/README before reporting bugs
+ * On Linux, png_have_msa is implemented by reading the pseudo-file
+ * "/proc/self/auxv".
+ *
+ * See contrib/mips-msa/README before reporting bugs.
  *
  * STATUS: SUPPORTED
  * BUG REPORTS: png-mng-implement@sourceforge.net
- *
- * png_have_msa implemented for Linux by reading the widely available
- * pseudo-file /proc/cpuinfo.
- *
- * This code is strict ANSI-C and is probably moderately portable; it does
- * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
  */
 
-#include <stdio.h>
-#include <string.h>
+#include <elf.h>
+#include <fcntl.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 static int
 png_have_msa(png_structp png_ptr)
 {
-   FILE *f = fopen("/proc/cpuinfo", "rb");
+   Elf64_auxv_t aux;
+   int fd;
+   int has_msa = 0;
 
-   char *string = "msa";
-   char word[10];
-
-   if (f != NULL)
+   fd = open("/proc/self/auxv", O_RDONLY);
+   if (fd >= 0)
    {
-      while(!feof(f))
+      while (read(fd, &aux, sizeof(Elf64_auxv_t)) == sizeof(Elf64_auxv_t))
       {
-         int ch = fgetc(f);
-         static int i = 0;
-
-         while(!(ch <= 32))
+         if (aux.a_type == AT_HWCAP)
          {
-            word[i++] = ch;
-            ch = fgetc(f);
+            uint64_t hwcap = aux.a_un.a_val;
+
+            has_msa = (hwcap >> 1) & 1;
+            break;
          }
-
-         int val = strcmp(string, word);
-
-         if (val == 0)
-            return 1;
-
-         i = 0;
-         memset(word, 0, 10);
       }
-
-      fclose(f);
+      close(fd);
    }
 #ifdef PNG_WARNINGS_SUPPORTED
    else
-      png_warning(png_ptr, "/proc/cpuinfo open failed");
+      png_warning(png_ptr, "/proc/self/auxv open failed");
 #endif
-   return 0;
+
+   return has_msa;
 }
diff --git a/contrib/oss-fuzz/README.txt b/contrib/oss-fuzz/README.txt
index 3b3656f..66d5242 100644
--- a/contrib/oss-fuzz/README.txt
+++ b/contrib/oss-fuzz/README.txt
@@ -1,4 +1,3 @@
-Last changed in libpng 1.6.33 [September 28, 2017]
 Copyright (c) 2017 Glenn Randers-Pehrson
 
 This code is released under the libpng license.
diff --git a/contrib/oss-fuzz/build.sh b/contrib/oss-fuzz/build.sh
index f9e1b07..7b8f026 100755
--- a/contrib/oss-fuzz/build.sh
+++ b/contrib/oss-fuzz/build.sh
@@ -1,4 +1,5 @@
 #!/bin/bash -eu
+
 # Copyright 2017-2018 Glenn Randers-Pehrson
 # Copyright 2016 Google Inc.
 #
@@ -14,8 +15,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-# Last changed in libpng 1.6.35 [July 15, 2018]
-#
 # Revisions by Glenn Randers-Pehrson, 2017:
 # 1. Build only the library, not the tools (changed "make -j$(nproc) all" to
 #     "make -j$(nproc) libpng16.la").
diff --git a/contrib/oss-fuzz/libpng_read_fuzzer.cc b/contrib/oss-fuzz/libpng_read_fuzzer.cc
index 7b30550..0190cf7 100644
--- a/contrib/oss-fuzz/libpng_read_fuzzer.cc
+++ b/contrib/oss-fuzz/libpng_read_fuzzer.cc
@@ -5,8 +5,6 @@
 // Use of this source code is governed by a BSD-style license that may
 // be found in the LICENSE file https://cs.chromium.org/chromium/src/LICENSE
 
-// Last changed in libpng 1.6.35 [July 15, 2018]
-
 // The modifications in 2017 by Glenn Randers-Pehrson include
 // 1. addition of a PNG_CLEANUP macro,
 // 2. setting the option to ignore ADLER32 checksums,
@@ -17,6 +15,7 @@
 
 #include <stddef.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 
 #include <vector>
@@ -60,7 +59,7 @@
       png_free(png_ptr, row_ptr);
     if (end_info_ptr)
       png_destroy_read_struct(&png_ptr, &info_ptr, &end_info_ptr);
-    else if (info_ptr) 
+    else if (info_ptr)
       png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
     else
       png_destroy_read_struct(&png_ptr, nullptr, nullptr);
@@ -78,6 +77,22 @@
   buf_state->data += length;
 }
 
+void* limited_malloc(png_structp, png_alloc_size_t size) {
+  // libpng may allocate large amounts of memory that the fuzzer reports as
+  // an error. In order to silence these errors, make libpng fail when trying
+  // to allocate a large amount. This allocator used to be in the Chromium
+  // version of this fuzzer.
+  // This number is chosen to match the default png_user_chunk_malloc_max.
+  if (size > 8000000)
+    return nullptr;
+
+  return malloc(size);
+}
+
+void default_free(png_structp, png_voidp ptr) {
+  return free(ptr);
+}
+
 static const int kPngHeaderSize = 8;
 
 // Entry point for LibFuzzer.
@@ -118,6 +133,9 @@
     return 0;
   }
 
+  // Use a custom allocator that fails for large allocations to avoid OOM.
+  png_set_mem_fn(png_handler.png_ptr, nullptr, limited_malloc, default_free);
+
   png_set_crc_action(png_handler.png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE);
 #ifdef PNG_IGNORE_ADLER32
   png_set_option(png_handler.png_ptr, PNG_IGNORE_ADLER32, PNG_OPTION_ON);
diff --git a/contrib/pngminus/.gitignore b/contrib/pngminus/.gitignore
new file mode 100644
index 0000000..5114c75
--- /dev/null
+++ b/contrib/pngminus/.gitignore
@@ -0,0 +1,11 @@
+# Compiled executables
+png2pnm
+png2pnm.exe
+png2pnm-static*
+pnm2png
+pnm2png.exe
+pnm2png-static*
+
+# Test artifacts
+*.png
+*.p[abgnp]m
diff --git a/contrib/pngminus/CHANGES.txt b/contrib/pngminus/CHANGES.txt
index 4e64e5e..85e590a 100644
--- a/contrib/pngminus/CHANGES.txt
+++ b/contrib/pngminus/CHANGES.txt
@@ -3,7 +3,7 @@
 copyright (C) 1999-2019 by Willem van Schaik <willem at schaik dot com>
 
 version 1.0 - 1999.10.15 - First version.
-        1.1 - 2015.07.29 - Fixed leaks (Glenn Randers-Pehrson)
+        1.1 - 2015.07.29 - Fix memory leaks (Glenn Randers-Pehrson)
         1.2 - 2017.04.22 - Add buffer-size check
         1.3 - 2017.08.24 - Fix potential overflow in buffer-size check
                            (Glenn Randers-Pehrson)
@@ -11,3 +11,4 @@
         1.5 - 2018.08.05 - Fix buffer overflow in tokenizer (Cosmin Truta)
         1.6 - 2018.08.05 - Improve portability and fix style (Cosmin Truta)
         1.7 - 2019.01.22 - Change license to MIT (Willem van Schaik)
+        1.8 - 2024.01.09 - Fix, improve, modernize (Cosmin Truta)
diff --git a/contrib/pngminus/CMakeLists.txt b/contrib/pngminus/CMakeLists.txt
index 1f815a5..d789364 100644
--- a/contrib/pngminus/CMakeLists.txt
+++ b/contrib/pngminus/CMakeLists.txt
@@ -1,24 +1,41 @@
-cmake_minimum_required(VERSION 3.1)
-cmake_policy(VERSION 3.1)
+# Copyright (c) 2018-2024 Cosmin Truta
+#
+# This software is released under the MIT license. For conditions of
+# distribution and use, see the LICENSE file part of this package.
+
+cmake_minimum_required(VERSION 3.5)
 
 project(PNGMINUS C)
 
-option(PNGMINUS_USE_STATIC_LIBRARIES "Use the static library builds" ON)
+option(PNGMINUS_USE_SYSTEM_PNG
+       "Use the libpng build found in the system" OFF)
 
-# libpng
-add_subdirectory(../.. libpng)
-include_directories(${CMAKE_CURRENT_SOURCE_DIR}/../..)
-include_directories(${CMAKE_CURRENT_BINARY_DIR}/libpng)
-if(PNGMINUS_USE_STATIC_LIBRARIES)
-  set(PNGMINUS_PNG_LIBRARY png_static)
-else()
-  set(PNGMINUS_PNG_LIBRARY png)
-endif()
-
-# png2pnm
 add_executable(png2pnm png2pnm.c)
-target_link_libraries(png2pnm ${PNGMINUS_PNG_LIBRARY})
-
-# pnm2png
 add_executable(pnm2png pnm2png.c)
-target_link_libraries(pnm2png ${PNGMINUS_PNG_LIBRARY})
+
+if(PNGMINUS_USE_SYSTEM_PNG)
+    # Use the system libpng.
+    find_package(PNG REQUIRED)
+    target_link_libraries(png2pnm PRIVATE PNG::PNG)
+    target_link_libraries(pnm2png PRIVATE PNG::PNG)
+else()
+    # Build and use the internal libpng.
+    # Configure libpng for static linking, to produce single-file executables.
+    set(PNG_STATIC ON
+        CACHE STRING "Build the internal libpng as a static library" FORCE)
+    set(PNG_SHARED OFF
+        CACHE STRING "Build the internal libpng as a shared library" FORCE)
+    set(PNG_FRAMEWORK OFF
+        CACHE STRING "Build the internal libpng as a framework bundle" FORCE)
+    add_subdirectory(../.. libpng)
+    target_include_directories(png2pnm PRIVATE
+        "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../..>"
+        "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/libpng>"
+    )
+    target_include_directories(pnm2png PRIVATE
+        "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../..>"
+        "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/libpng>"
+    )
+    target_link_libraries(png2pnm PRIVATE png_static)
+    target_link_libraries(pnm2png PRIVATE png_static)
+endif()
diff --git a/contrib/pngminus/LICENSE.txt b/contrib/pngminus/LICENSE.txt
index 00878a9..a8d4137 100644
--- a/contrib/pngminus/LICENSE.txt
+++ b/contrib/pngminus/LICENSE.txt
@@ -16,7 +16,7 @@
 The software is provided "as is", without warranty of any kind, express or
 implied, including but not limited to the warranties of merchantability,
 fitness for a particular purpose and noninfringement. In no event shall the
-authors or copyight holders be liable for any claim, damages or other
+authors or copyright holders be liable for any claim, damages or other
 liability, whether in an action of contract, tort or otherwise, arising from,
 out of or in connection with the software or the use or other dealings in the
 software.
diff --git a/contrib/pngminus/png2pnm.c b/contrib/pngminus/png2pnm.c
index 5fef7ed..f9d5138 100644
--- a/contrib/pngminus/png2pnm.c
+++ b/contrib/pngminus/png2pnm.c
@@ -14,15 +14,10 @@
 #define BOOL unsigned char
 #endif
 #ifndef TRUE
-#define TRUE (BOOL) 1
+#define TRUE ((BOOL) 1)
 #endif
 #ifndef FALSE
-#define FALSE (BOOL) 0
-#endif
-
-/* make png2pnm verbose so we can find problems (needs to be before png.h) */
-#ifndef PNG_DEBUG
-#define PNG_DEBUG 0
+#define FALSE ((BOOL) 0)
 #endif
 
 #include "png.h"
@@ -33,6 +28,9 @@
 void usage ();
 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
               BOOL raw, BOOL alpha);
+BOOL do_png2pnm (png_struct *png_ptr, png_info *info_ptr,
+                 FILE *pnm_file, FILE *alpha_file,
+                 BOOL raw, BOOL alpha);
 
 /*
  *  main
@@ -43,9 +41,12 @@
   FILE *fp_rd = stdin;
   FILE *fp_wr = stdout;
   FILE *fp_al = NULL;
+  const char *fname_wr = NULL;
+  const char *fname_al = NULL;
   BOOL raw = TRUE;
   BOOL alpha = FALSE;
   int argi;
+  int ret;
 
   for (argi = 1; argi < argc; argi++)
   {
@@ -64,6 +65,7 @@
           argi++;
           if ((fp_al = fopen (argv[argi], "wb")) == NULL)
           {
+            fname_al = argv[argi];
             fprintf (stderr, "PNM2PNG\n");
             fprintf (stderr, "Error:  cannot create alpha-channel file %s\n",
                      argv[argi]);
@@ -94,6 +96,7 @@
     }
     else if (fp_wr == stdout)
     {
+      fname_wr = argv[argi];
       if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
       {
         fprintf (stderr, "PNG2PNM\n");
@@ -119,12 +122,7 @@
 #endif
 
   /* call the conversion program itself */
-  if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
-  {
-    fprintf (stderr, "PNG2PNM\n");
-    fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");
-    exit (1);
-  }
+  ret = png2pnm (fp_rd, fp_wr, fp_al, raw, alpha);
 
   /* close input file */
   fclose (fp_rd);
@@ -134,6 +132,17 @@
   if (alpha)
     fclose (fp_al);
 
+  if (!ret)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  unsuccessful conversion of PNG-image\n");
+    if (fname_wr)
+      remove (fname_wr); /* no broken output file shall remain behind */
+    if (fname_al)
+      remove (fname_al); /* ditto */
+    exit (1);
+  }
+
   return 0;
 }
 
@@ -163,35 +172,11 @@
 BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,
               BOOL raw, BOOL alpha)
 {
-  png_struct    *png_ptr = NULL;
-  png_info      *info_ptr = NULL;
-  png_byte      buf[8];
-  png_byte      *png_pixels = NULL;
-  png_byte      **row_pointers = NULL;
-  png_byte      *pix_ptr = NULL;
-  png_uint_32   row_bytes;
+  png_struct    *png_ptr;
+  png_info      *info_ptr;
+  BOOL          ret;
 
-  png_uint_32   width;
-  png_uint_32   height;
-  int           bit_depth;
-  int           channels;
-  int           color_type;
-  int           alpha_present;
-  int           row, col;
-  int           ret;
-  int           i;
-  long          dep_16;
-
-  /* read and check signature in PNG file */
-  ret = fread (buf, 1, 8, png_file);
-  if (ret != 8)
-    return FALSE;
-
-  ret = png_sig_cmp (buf, 0, 8);
-  if (ret != 0)
-    return FALSE;
-
-  /* create png and info structures */
+  /* initialize the libpng context for reading from png_file */
 
   png_ptr = png_create_read_struct (png_get_libpng_ver(NULL),
                                     NULL, NULL, NULL);
@@ -208,31 +193,47 @@
   if (setjmp (png_jmpbuf (png_ptr)))
   {
     png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-    return FALSE;
+    return FALSE; /* generic libpng error */
   }
 
-  /* set up the input control for C streams */
   png_init_io (png_ptr, png_file);
-  png_set_sig_bytes (png_ptr, 8); /* we already read the 8 signature bytes */
 
-  /* read the file information */
-  png_read_info (png_ptr, info_ptr);
+  /* do the actual conversion */
+  ret = do_png2pnm (png_ptr, info_ptr, pnm_file, alpha_file, raw, alpha);
 
-  /* get size and bit-depth of the PNG-image */
-  png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
-                NULL, NULL, NULL);
+  /* clean up the libpng structures and their internally-managed data */
+  png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
 
-  /* set-up the transformations */
+  return ret;
+}
 
-  /* transform paletted images into full-color rgb */
-  if (color_type == PNG_COLOR_TYPE_PALETTE)
-    png_set_expand (png_ptr);
-  /* expand images to bit-depth 8 (only applicable for grayscale images) */
-  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
-    png_set_expand (png_ptr);
-  /* transform transparency maps into full alpha-channel */
-  if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
-    png_set_expand (png_ptr);
+/*
+ *  do_png2pnm - does the conversion in a fully-initialized libpng context
+ */
+
+BOOL do_png2pnm (png_struct *png_ptr, png_info *info_ptr,
+                 FILE *pnm_file, FILE *alpha_file,
+                 BOOL raw, BOOL alpha)
+{
+  png_byte      **row_pointers;
+  png_byte      *pix_ptr;
+  png_uint_32   width;
+  png_uint_32   height;
+  int           bit_depth;
+  int           channels;
+  int           color_type;
+  int           alpha_present;
+  png_uint_32   row, col, i;
+  long          dep_16;
+
+  /* set up the image transformations that are necessary for the PNM format */
+
+  /* set up (if applicable) the expansion of paletted images to full-color rgb,
+   * and the expansion of transparency maps to full alpha-channel */
+  png_set_expand (png_ptr);
+
+  /* set up (if applicable) the expansion of grayscale images to bit-depth 8 */
+  png_set_expand_gray_1_2_4_to_8 (png_ptr);
 
 #ifdef NJET
   /* downgrade 16-bit images to 8-bit */
@@ -242,30 +243,22 @@
   if (color_type == PNG_COLOR_TYPE_GRAY ||
       color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
     png_set_gray_to_rgb (png_ptr);
-  /* only if file has a file gamma, we do a correction */
-  if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
-    png_set_gamma (png_ptr, (double) 2.2, file_gamma);
+  /* if the PNG image has a gAMA chunk then gamma-correct the output image */
+  {
+    double file_gamma;
+    if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
+      png_set_gamma (png_ptr, (double) 2.2, file_gamma);
+  }
 #endif
 
-  /* all transformations have been registered; now update info_ptr data,
-   * get rowbytes and channels, and allocate image memory */
+  /* read the image file, with all of the above image transforms applied */
+  png_read_png (png_ptr, info_ptr, 0, NULL);
 
-  png_read_update_info (png_ptr, info_ptr);
-
-  /* get the new color-type and bit-depth (after expansion/stripping) */
+  /* get the image size, bit-depth and color-type */
   png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
                 NULL, NULL, NULL);
 
-  /* check for 16-bit files */
-  if (bit_depth == 16)
-  {
-    raw = FALSE;
-#if defined(O_BINARY) && (O_BINARY != 0)
-    setmode (fileno (pnm_file), O_BINARY);
-#endif
-  }
-
-  /* calculate new number of channels and store alpha-presence */
+  /* calculate the number of channels and store alpha-presence */
   if (color_type == PNG_COLOR_TYPE_GRAY)
     channels = 1;
   else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -282,47 +275,12 @@
   if (alpha && !alpha_present)
   {
     fprintf (stderr, "PNG2PNM\n");
-    fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");
-    exit (1);
-  }
-
-  /* row_bytes is the width x number of channels x (bit-depth / 8) */
-  row_bytes = png_get_rowbytes (png_ptr, info_ptr);
-
-  if ((row_bytes == 0) ||
-      ((size_t) height > (size_t) (-1) / (size_t) row_bytes))
-  {
-    /* too big */
-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-    return FALSE;
-  }
-  if ((png_pixels = (png_byte *)
-       malloc ((size_t) row_bytes * (size_t) height)) == NULL)
-  {
-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    fprintf (stderr, "Warning:  no alpha channel in PNG file\n");
     return FALSE;
   }
 
-  if ((row_pointers = (png_byte **)
-       malloc ((size_t) height * sizeof (png_byte *))) == NULL)
-  {
-    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-    free (png_pixels);
-    return FALSE;
-  }
-
-  /* set the individual row_pointers to point at the correct offsets */
-  for (i = 0; i < ((int) height); i++)
-    row_pointers[i] = png_pixels + i * row_bytes;
-
-  /* now we can go ahead and just read the whole image */
-  png_read_image (png_ptr, row_pointers);
-
-  /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
-  png_read_end (png_ptr, info_ptr);
-
-  /* clean up after the read, and free any memory allocated - REQUIRED */
-  png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+  /* get address of internally-allocated image data */
+  row_pointers = png_get_rows (png_ptr, info_ptr);
 
   /* write header of PNM file */
 
@@ -353,24 +311,27 @@
   }
 
   /* write data to PNM file */
-  pix_ptr = png_pixels;
 
-  for (row = 0; row < (int) height; row++)
+  for (row = 0; row < height; row++)
   {
-    for (col = 0; col < (int) width; col++)
+    pix_ptr = row_pointers[row];
+    for (col = 0; col < width; col++)
     {
-      for (i = 0; i < (channels - alpha_present); i++)
+      for (i = 0; i < (png_uint_32) (channels - alpha_present); i++)
       {
         if (raw)
         {
           fputc ((int) *pix_ptr++, pnm_file);
+          if (bit_depth == 16)
+            fputc ((int) *pix_ptr++, pnm_file);
         }
         else
         {
           if (bit_depth == 16)
           {
-            dep_16 = (long) *pix_ptr++;
-            fprintf (pnm_file, "%ld ", (dep_16 << 8) + ((long) *pix_ptr++));
+            dep_16 = ((long) *pix_ptr++) << 8;
+            dep_16 += ((long) *pix_ptr++);
+            fprintf (pnm_file, "%ld ", dep_16);
           }
           else
           {
@@ -382,22 +343,27 @@
       {
         if (!alpha)
         {
-          pix_ptr++; /* alpha */
+          /* skip the alpha-channel */
+          pix_ptr++;
           if (bit_depth == 16)
             pix_ptr++;
         }
-        else /* output alpha-channel as pgm file */
+        else
         {
+          /* output the alpha-channel as pgm file */
           if (raw)
           {
             fputc ((int) *pix_ptr++, alpha_file);
+            if (bit_depth == 16)
+              fputc ((int) *pix_ptr++, alpha_file);
           }
           else
           {
             if (bit_depth == 16)
             {
-              dep_16 = (long) *pix_ptr++;
-              fprintf (alpha_file, "%ld ", (dep_16 << 8) + (long) *pix_ptr++);
+              dep_16 = ((long) *pix_ptr++) << 8;
+              dep_16 += ((long) *pix_ptr++);
+              fprintf (alpha_file, "%ld ", dep_16);
             }
             else
             {
@@ -417,11 +383,5 @@
         fprintf (pnm_file, "\n");
   } /* end for row */
 
-  if (row_pointers != NULL)
-    free (row_pointers);
-  if (png_pixels != NULL)
-    free (png_pixels);
-
   return TRUE;
-
 } /* end of source */
diff --git a/contrib/pngminus/pnm2png.c b/contrib/pngminus/pnm2png.c
index a2c2551..052fd32 100644
--- a/contrib/pngminus/pnm2png.c
+++ b/contrib/pngminus/pnm2png.c
@@ -6,6 +6,7 @@
  *  distribution and use, see the LICENSE file part of this package.
  */
 
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <fcntl.h>
@@ -14,15 +15,10 @@
 #define BOOL unsigned char
 #endif
 #ifndef TRUE
-#define TRUE (BOOL) 1
+#define TRUE ((BOOL) 1)
 #endif
 #ifndef FALSE
-#define FALSE (BOOL) 0
-#endif
-
-/* make pnm2png verbose so we can find problems (needs to be before png.h) */
-#ifndef PNG_DEBUG
-#define PNG_DEBUG 0
+#define FALSE ((BOOL) 0)
 #endif
 
 #include "png.h"
@@ -33,9 +29,14 @@
 void usage ();
 BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
               BOOL interlace, BOOL alpha);
-void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size);
-png_uint_32 get_data (FILE *pnm_file, int depth);
-png_uint_32 get_value (FILE *pnm_file, int depth);
+BOOL do_pnm2png (png_struct *png_ptr, png_info *info_ptr,
+                 FILE *pnm_file, FILE *alpha_file,
+                 BOOL interlace, BOOL alpha);
+int fscan_pnm_magic (FILE *pnm_file, char *magic_buf, size_t magic_buf_size);
+int fscan_pnm_token (FILE *pnm_file, char *token_buf, size_t token_buf_size);
+int fscan_pnm_uint_32 (FILE *pnm_file, png_uint_32 *num_ptr);
+png_uint_32 get_pnm_data (FILE *pnm_file, int depth);
+png_uint_32 get_pnm_value (FILE *pnm_file, int depth);
 
 /*
  *  main
@@ -46,9 +47,11 @@
   FILE *fp_rd = stdin;
   FILE *fp_al = NULL;
   FILE *fp_wr = stdout;
+  const char *fname_wr = NULL;
   BOOL interlace = FALSE;
   BOOL alpha = FALSE;
   int argi;
+  int ret;
 
   for (argi = 1; argi < argc; argi++)
   {
@@ -94,6 +97,7 @@
     }
     else if (fp_wr == stdout)
     {
+      fname_wr = argv[argi];
       if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
       {
         fprintf (stderr, "PNM2PNG\n");
@@ -121,12 +125,7 @@
 #endif
 
   /* call the conversion program itself */
-  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
-  {
-    fprintf (stderr, "PNM2PNG\n");
-    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
-    exit (1);
-  }
+  ret = pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha);
 
   /* close input file */
   fclose (fp_rd);
@@ -136,6 +135,15 @@
   if (alpha)
     fclose (fp_al);
 
+  if (!ret)
+  {
+    fprintf (stderr, "PNM2PNG\n");
+    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
+    if (fname_wr)
+      remove (fname_wr); /* no broken output file shall remain behind */
+    exit (1);
+  }
+
   return 0;
 }
 
@@ -163,77 +171,98 @@
 BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file,
               BOOL interlace, BOOL alpha)
 {
-  png_struct    *png_ptr = NULL;
-  png_info      *info_ptr = NULL;
-  png_byte      *png_pixels = NULL;
-  png_byte      **row_pointers = NULL;
-  png_byte      *pix_ptr = NULL;
-  volatile png_uint_32 row_bytes;
+  png_struct    *png_ptr;
+  png_info      *info_ptr;
+  BOOL          ret;
 
-  char          type_token[16];
-  char          width_token[16];
-  char          height_token[16];
-  char          maxval_token[16];
-  volatile int  color_type = 1;
-  unsigned long ul_width = 0, ul_alpha_width = 0;
-  unsigned long ul_height = 0, ul_alpha_height = 0;
-  unsigned long ul_maxval = 0;
-  volatile png_uint_32 width = 0, height = 0;
-  volatile png_uint_32 alpha_width = 0, alpha_height = 0;
-  png_uint_32   maxval;
-  volatile int  bit_depth = 0;
-  int           channels = 0;
-  int           alpha_depth = 0;
-  int           alpha_present = 0;
-  int           row, col;
-  BOOL          raw, alpha_raw = FALSE;
-#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  /* initialize the libpng context for writing to png_file */
+
+  png_ptr = png_create_write_struct (png_get_libpng_ver(NULL),
+                                     NULL, NULL, NULL);
+  if (!png_ptr)
+    return FALSE; /* out of memory */
+
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_write_struct (&png_ptr, NULL);
+    return FALSE; /* out of memory */
+  }
+
+  if (setjmp (png_jmpbuf (png_ptr)))
+  {
+    png_destroy_write_struct (&png_ptr, &info_ptr);
+    return FALSE; /* generic libpng error */
+  }
+
+  png_init_io (png_ptr, png_file);
+
+  /* do the actual conversion */
+  ret = do_pnm2png (png_ptr, info_ptr, pnm_file, alpha_file, interlace, alpha);
+
+  /* clean up the libpng structures and their internally-managed data */
+  png_destroy_write_struct (&png_ptr, &info_ptr);
+
+  return ret;
+}
+
+/*
+ *  do_pnm2png - does the conversion in a fully-initialized libpng context
+ */
+
+BOOL do_pnm2png (png_struct *png_ptr, png_info *info_ptr,
+                 FILE *pnm_file, FILE *alpha_file,
+                 BOOL interlace, BOOL alpha)
+{
+  png_byte      **row_pointers;
+  png_byte      *pix_ptr;
+  int           bit_depth;
+  int           color_type;
+  int           channels;
+  char          magic_token[4];
+  BOOL          raw;
+  png_uint_32   width, height, maxval;
+  png_uint_32   row_bytes;
+  png_uint_32   row, col;
+  png_uint_32   val16, i;
+  png_uint_32   alpha_width = 0, alpha_height = 0;
+  int           alpha_depth = 0, alpha_present = 0;
+  BOOL          alpha_raw = FALSE;
   BOOL          packed_bitmap = FALSE;
-#endif
-  png_uint_32   tmp16;
-  int           i;
 
   /* read header of PNM file */
 
-  get_token (pnm_file, type_token, sizeof (type_token));
-  if (type_token[0] != 'P')
-  {
-    return FALSE;
-  }
-  else if ((type_token[1] == '1') || (type_token[1] == '4'))
-  {
-#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-    raw = (type_token[1] == '4');
-    color_type = PNG_COLOR_TYPE_GRAY;
-    get_token (pnm_file, width_token, sizeof (width_token));
-    sscanf (width_token, "%lu", &ul_width);
-    width = (png_uint_32) ul_width;
-    get_token (pnm_file, height_token, sizeof (height_token));
-    sscanf (height_token, "%lu", &ul_height);
-    height = (png_uint_32) ul_height;
-    bit_depth = 1;
-    packed_bitmap = TRUE;
-#else
-    fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and\n");
-    fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
-    return FALSE;
-#endif
-  }
-  else if ((type_token[1] == '2') || (type_token[1] == '5'))
-  {
-    raw = (type_token[1] == '5');
-    color_type = PNG_COLOR_TYPE_GRAY;
-    get_token (pnm_file, width_token, sizeof (width_token));
-    sscanf (width_token, "%lu", &ul_width);
-    width = (png_uint_32) ul_width;
-    get_token (pnm_file, height_token, sizeof (height_token));
-    sscanf (height_token, "%lu", &ul_height);
-    height = (png_uint_32) ul_height;
-    get_token (pnm_file, maxval_token, sizeof (maxval_token));
-    sscanf (maxval_token, "%lu", &ul_maxval);
-    maxval = (png_uint_32) ul_maxval;
+  if (fscan_pnm_magic (pnm_file, magic_token, sizeof (magic_token)) != 1)
+    return FALSE; /* not a PNM file */
 
-    if (maxval <= 1)
+  if ((magic_token[1] == '1') || (magic_token[1] == '4'))
+  {
+    if ((fscan_pnm_uint_32 (pnm_file, &width) != 1) ||
+        (fscan_pnm_uint_32 (pnm_file, &height) != 1))
+      return FALSE; /* bad PBM file header */
+  } else if ((magic_token[1] == '2') || (magic_token[1] == '5') ||
+             (magic_token[1] == '3') || (magic_token[1] == '6'))
+  {
+    if ((fscan_pnm_uint_32 (pnm_file, &width) != 1) ||
+        (fscan_pnm_uint_32 (pnm_file, &height) != 1) ||
+        (fscan_pnm_uint_32 (pnm_file, &maxval) != 1))
+      return FALSE; /* bad PGM/PPM file header */
+  }
+
+  if ((magic_token[1] == '1') || (magic_token[1] == '4'))
+  {
+    raw = (magic_token[1] == '4');
+    bit_depth = 1;
+    color_type = PNG_COLOR_TYPE_GRAY;
+    packed_bitmap = TRUE;
+  }
+  else if ((magic_token[1] == '2') || (magic_token[1] == '5'))
+  {
+    raw = (magic_token[1] == '5');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    if (maxval == 0)
+      return FALSE;
+    else if (maxval == 1)
       bit_depth = 1;
     else if (maxval <= 3)
       bit_depth = 2;
@@ -246,20 +275,13 @@
     else /* maxval > 65535U */
       return FALSE;
   }
-  else if ((type_token[1] == '3') || (type_token[1] == '6'))
+  else if ((magic_token[1] == '3') || (magic_token[1] == '6'))
   {
-    raw = (type_token[1] == '6');
+    raw = (magic_token[1] == '6');
     color_type = PNG_COLOR_TYPE_RGB;
-    get_token (pnm_file, width_token, sizeof (width_token));
-    sscanf (width_token, "%lu", &ul_width);
-    width = (png_uint_32) ul_width;
-    get_token (pnm_file, height_token, sizeof (height_token));
-    sscanf (height_token, "%lu", &ul_height);
-    height = (png_uint_32) ul_height;
-    get_token (pnm_file, maxval_token, sizeof (maxval_token));
-    sscanf (maxval_token, "%lu", &ul_maxval);
-    maxval = (png_uint_32) ul_maxval;
-    if (maxval <= 1)
+    if (maxval == 0)
+      return FALSE;
+    else if (maxval == 1)
       bit_depth = 1;
     else if (maxval <= 3)
       bit_depth = 2;
@@ -272,6 +294,11 @@
     else /* maxval > 65535U */
       return FALSE;
   }
+  else if (magic_token[1] == '7')
+  {
+    fprintf (stderr, "PNM2PNG can't read PAM (P7) files\n");
+    return FALSE;
+  }
   else
   {
     return FALSE;
@@ -281,51 +308,36 @@
 
   if (alpha)
   {
-    if (color_type == PNG_COLOR_TYPE_GRAY)
-      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
-    if (color_type == PNG_COLOR_TYPE_RGB)
-      color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    if ((fscan_pnm_magic (alpha_file, magic_token, sizeof (magic_token)) != 1)
+        || ((magic_token[1] != '2') && (magic_token[1] != '5')))
+      return FALSE; /* not a PGM file */
 
-    get_token (alpha_file, type_token, sizeof (type_token));
-    if (type_token[0] != 'P')
-    {
+    if ((fscan_pnm_uint_32 (alpha_file, &alpha_width) != 1) ||
+        (fscan_pnm_uint_32 (alpha_file, &alpha_height) != 1) ||
+        (fscan_pnm_uint_32 (alpha_file, &maxval) != 1))
+      return FALSE; /* bad PGM file header */
+
+    if ((alpha_width != width) || (alpha_height != height))
+      return FALSE; /* mismatched PGM dimensions */
+
+    alpha_raw = (magic_token[1] == '5');
+    color_type |= PNG_COLOR_MASK_ALPHA;
+    if (maxval == 0)
       return FALSE;
-    }
-    else if ((type_token[1] == '2') || (type_token[1] == '5'))
-    {
-      alpha_raw = (type_token[1] == '5');
-      get_token (alpha_file, width_token, sizeof (width_token));
-      sscanf (width_token, "%lu", &ul_alpha_width);
-      alpha_width = (png_uint_32) ul_alpha_width;
-      if (alpha_width != width)
-        return FALSE;
-      get_token (alpha_file, height_token, sizeof (height_token));
-      sscanf (height_token, "%lu", &ul_alpha_height);
-      alpha_height = (png_uint_32) ul_alpha_height;
-      if (alpha_height != height)
-        return FALSE;
-      get_token (alpha_file, maxval_token, sizeof (maxval_token));
-      sscanf (maxval_token, "%lu", &ul_maxval);
-      maxval = (png_uint_32) ul_maxval;
-      if (maxval <= 1)
-        alpha_depth = 1;
-      else if (maxval <= 3)
-        alpha_depth = 2;
-      else if (maxval <= 15)
-        alpha_depth = 4;
-      else if (maxval <= 255)
-        alpha_depth = 8;
-      else if (maxval <= 65535U)
-        alpha_depth = 16;
-      else /* maxval > 65535U */
-        return FALSE;
-      if (alpha_depth != bit_depth)
-        return FALSE;
-    }
-    else
-    {
+    else if (maxval == 1)
+      alpha_depth = 1;
+    else if (maxval <= 3)
+      alpha_depth = 2;
+    else if (maxval <= 15)
+      alpha_depth = 4;
+    else if (maxval <= 255)
+      alpha_depth = 8;
+    else if (maxval <= 65535U)
+      alpha_depth = 16;
+    else /* maxval > 65535U */
       return FALSE;
-    }
+    if (alpha_depth != bit_depth)
+      return FALSE;
   } /* end if alpha */
 
   /* calculate the number of channels and store alpha-presence */
@@ -337,21 +349,17 @@
     channels = 3;
   else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
     channels = 4;
-#if 0
   else
-    channels = 0; /* cannot happen */
-#endif
+    return FALSE; /* NOTREACHED */
 
   alpha_present = (channels - 1) % 2;
 
-#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
   if (packed_bitmap)
   {
     /* row data is as many bytes as can fit width x channels x bit_depth */
     row_bytes = (width * channels * bit_depth + 7) / 8;
   }
   else
-#endif
   {
     /* row_bytes is the width x number of channels x (bit-depth / 8) */
     row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
@@ -363,50 +371,59 @@
     /* too big */
     return FALSE;
   }
-  if ((png_pixels = (png_byte *)
-       malloc ((size_t) row_bytes * (size_t) height)) == NULL)
+
+  /* allocate the rows using the same memory layout as libpng, and transfer
+   * their ownership to libpng, with the responsibility to clean everything up;
+   * please note the use of png_calloc instead of png_malloc */
+  row_pointers = (png_byte **)
+                 png_calloc (png_ptr, height * sizeof (png_byte *));
+  png_set_rows (png_ptr, info_ptr, row_pointers);
+  png_data_freer (png_ptr, info_ptr, PNG_DESTROY_WILL_FREE_DATA, PNG_FREE_ALL);
+  for (row = 0; row < height; row++)
   {
-    /* out of memory */
-    return FALSE;
+    /* the individual rows should only be allocated after all the previous
+     * steps completed successfully, because libpng must handle correctly
+     * any image allocation left incomplete after an out-of-memory error */
+    row_pointers[row] = (png_byte *) png_malloc (png_ptr, row_bytes);
   }
 
-  /* read data from PNM file */
-  pix_ptr = png_pixels;
+  /* read the data from PNM file */
 
-  for (row = 0; row < (int) height; row++)
+  for (row = 0; row < height; row++)
   {
-#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+    pix_ptr = row_pointers[row];
     if (packed_bitmap)
     {
-      for (i = 0; i < (int) row_bytes; i++)
+      for (i = 0; i < row_bytes; i++)
       {
         /* png supports this format natively so no conversion is needed */
-        *pix_ptr++ = get_data (pnm_file, 8);
+        *pix_ptr++ = get_pnm_data (pnm_file, 8);
       }
     }
     else
-#endif
     {
-      for (col = 0; col < (int) width; col++)
+      for (col = 0; col < width; col++)
       {
-        for (i = 0; i < (channels - alpha_present); i++)
+        for (i = 0; i < (png_uint_32) (channels - alpha_present); i++)
         {
           if (raw)
           {
-            *pix_ptr++ = get_data (pnm_file, bit_depth);
+            *pix_ptr++ = get_pnm_data (pnm_file, bit_depth);
+            if (bit_depth == 16)
+              *pix_ptr++ = get_pnm_data (pnm_file, bit_depth);
           }
           else
           {
             if (bit_depth <= 8)
             {
-              *pix_ptr++ = get_value (pnm_file, bit_depth);
+              *pix_ptr++ = get_pnm_value (pnm_file, bit_depth);
             }
             else
             {
-              tmp16 = get_value (pnm_file, bit_depth);
-              *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+              val16 = get_pnm_value (pnm_file, bit_depth);
+              *pix_ptr = (png_byte) ((val16 >> 8) & 0xFF);
               pix_ptr++;
-              *pix_ptr = (png_byte) (tmp16 & 0xFF);
+              *pix_ptr = (png_byte) (val16 & 0xFF);
               pix_ptr++;
             }
           }
@@ -416,19 +433,21 @@
         {
           if (alpha_raw)
           {
-            *pix_ptr++ = get_data (alpha_file, alpha_depth);
+            *pix_ptr++ = get_pnm_data (alpha_file, alpha_depth);
+            if (alpha_depth == 16)
+              *pix_ptr++ = get_pnm_data (alpha_file, alpha_depth);
           }
           else
           {
             if (alpha_depth <= 8)
             {
-              *pix_ptr++ = get_value (alpha_file, bit_depth);
+              *pix_ptr++ = get_pnm_value (alpha_file, bit_depth);
             }
             else
             {
-              tmp16 = get_value (alpha_file, bit_depth);
-              *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
-              *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+              val16 = get_pnm_value (alpha_file, bit_depth);
+              *pix_ptr++ = (png_byte) ((val16 >> 8) & 0xFF);
+              *pix_ptr++ = (png_byte) (val16 & 0xFF);
             }
           }
         } /* end if alpha */
@@ -436,63 +455,19 @@
     } /* end for col */
   } /* end for row */
 
-  /* prepare the standard PNG structures */
-  png_ptr = png_create_write_struct (png_get_libpng_ver(NULL),
-                                     NULL, NULL, NULL);
-  if (!png_ptr)
-  {
-    free (png_pixels);
-    return FALSE;
-  }
-  info_ptr = png_create_info_struct (png_ptr);
-  if (!info_ptr)
-  {
-    png_destroy_write_struct (&png_ptr, NULL);
-    free (png_pixels);
-    return FALSE;
-  }
-
-#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-  if (packed_bitmap == TRUE)
-  {
-    png_set_packing (png_ptr);
-    png_set_invert_mono (png_ptr);
-  }
-#endif
-
-  if (setjmp (png_jmpbuf (png_ptr)))
-  {
-    png_destroy_write_struct (&png_ptr, &info_ptr);
-    free (png_pixels);
-    return FALSE;
-  }
-
-  /* initialize the png structure */
-  png_init_io (png_ptr, png_file);
-
   /* we're going to write more or less the same PNG as the input file */
   png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
                 (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
                 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
-  /* write the file header information */
-  png_write_info (png_ptr, info_ptr);
-
-  /* if needed we will allocate memory for an new array of row-pointers */
-  if (row_pointers == NULL)
+  if (packed_bitmap == TRUE)
   {
-    if ((row_pointers = (png_byte **)
-         malloc (height * sizeof (png_byte *))) == NULL)
-    {
-      png_destroy_write_struct (&png_ptr, &info_ptr);
-      free (png_pixels);
-      return FALSE;
-    }
+    png_set_packing (png_ptr);
+    png_set_invert_mono (png_ptr);
   }
 
-  /* set the individual row_pointers to point at the correct offsets */
-  for (i = 0; i < (int) height; i++)
-    row_pointers[i] = png_pixels + i * row_bytes;
+  /* write the file header information */
+  png_write_info (png_ptr, info_ptr);
 
   /* write out the entire image data in one call */
   png_write_image (png_ptr, row_pointers);
@@ -500,22 +475,46 @@
   /* write the additional chunks to the PNG file (not really needed) */
   png_write_end (png_ptr, info_ptr);
 
-  /* clean up after the write, and free any memory allocated */
-  png_destroy_write_struct (&png_ptr, &info_ptr);
-
-  if (row_pointers != NULL)
-    free (row_pointers);
-  if (png_pixels != NULL)
-    free (png_pixels);
-
   return TRUE;
 } /* end of pnm2png */
 
 /*
- * get_token - gets the first string after whitespace
+ * fscan_pnm_magic - like fscan_pnm_token below, but expects the magic string
+ *                   to start immediately, without any comment or whitespace,
+ *                   and to match the regex /^P[1-9]$/
  */
 
-void get_token (FILE *pnm_file, char *token_buf, size_t token_buf_size)
+int fscan_pnm_magic (FILE *pnm_file, char *magic_buf, size_t magic_buf_size)
+{
+  int ret;
+
+  ret = fgetc (pnm_file);
+  if (ret == EOF) return 0;
+  ungetc (ret, pnm_file);
+  if (ret != 'P') return 0;
+
+  /* the string buffer must be at least four bytes long, i.e., the capacity
+   * required for strings of at least three characters long, i.e., the minimum
+   * required for ensuring that our magic string is exactly two characters long
+   */
+  if (magic_buf_size < 4) return -1;
+
+  ret = fscan_pnm_token (pnm_file, magic_buf, magic_buf_size);
+  if (ret < 1) return ret;
+
+  if ((magic_buf[1] < '1') || (magic_buf[1] > '9')) return 0;
+  if (magic_buf[2] != '\0') return 0;
+
+  return 1;
+}
+
+/*
+ * fscan_pnm_token - extracts the first string token after whitespace,
+ *                   and (like fscanf) returns the number of successful
+ *                   extractions, which can be either 0 or 1
+ */
+
+int fscan_pnm_token (FILE *pnm_file, char *token_buf, size_t token_buf_size)
 {
   size_t i = 0;
   int ret;
@@ -543,29 +542,66 @@
   {
     ret = fgetc (pnm_file);
     if (ret == EOF) break;
+    if (ret == '0')
+    {
+      /* avoid storing more than one leading '0' in the token buffer,
+       * to ensure that all valid (in-range) numeric inputs can fit in. */
+      if ((i == 0) && (token_buf[i] == '0')) continue;
+    }
     if (++i == token_buf_size - 1) break;
     token_buf[i] = (char) ret;
   }
   while ((ret != '\n') && (ret != '\r') && (ret != ' '));
 
   token_buf[i] = '\0';
-
-  return;
+  return (i > 0) ? 1 : 0;
 }
 
 /*
- *  get_data - takes first byte and converts into next pixel value,
- *             taking as much bits as defined by bit-depth and
- *             using the bit-depth to fill up a byte (0Ah -> AAh)
+ * fscan_pnm_uint_32 - like fscan_token above, but expects the extracted token
+ *                     to be numeric, and converts it to an unsigned 32-bit int
  */
 
-png_uint_32 get_data (FILE *pnm_file, int depth)
+int fscan_pnm_uint_32 (FILE *pnm_file, png_uint_32 *num_ptr)
+{
+  char token[16];
+  unsigned long token_value;
+  int ret;
+
+  ret = fscan_pnm_token (pnm_file, token, sizeof (token));
+  if (ret < 1) return ret;
+
+  if ((token[0] < '0') && (token[0] > '9'))
+    return 0; /* the token starts with junk, or a +/- sign, which is invalid */
+
+  ret = sscanf (token, "%lu%*c", &token_value);
+  if (ret != 1)
+    return 0; /* the token ends with junk */
+
+  *num_ptr = (png_uint_32) token_value;
+
+#if ULONG_MAX > 0xFFFFFFFFUL
+  /* saturate the converted number, following the fscanf convention */
+  if (token_value > 0xFFFFFFFFUL)
+    *num_ptr = 0xFFFFFFFFUL;
+#endif
+
+  return 1;
+}
+
+/*
+ *  get_pnm_data - takes first byte and converts into next pixel value,
+ *                 taking as many bits as defined by bit-depth and
+ *                 using the bit-depth to fill up a byte (0x0A -> 0xAA)
+ */
+
+png_uint_32 get_pnm_data (FILE *pnm_file, int depth)
 {
   static int bits_left = 0;
   static int old_value = 0;
   static int mask = 0;
-  int i;
   png_uint_32 ret_value;
+  int i;
 
   if (mask == 0)
     for (i = 0; i < depth; i++)
@@ -573,7 +609,11 @@
 
   if (bits_left <= 0)
   {
+    /* FIXME:
+     * signal the premature end of file, instead of pretending to read zeroes
+     */
     old_value = fgetc (pnm_file);
+    if (old_value == EOF) return 0;
     bits_left = 8;
   }
 
@@ -588,25 +628,28 @@
 }
 
 /*
- *  get_value - takes first (numeric) string and converts into number,
- *              using the bit-depth to fill up a byte (0Ah -> AAh)
+ *  get_pnm_value - takes first (numeric) string and converts into number,
+ *                  using the bit-depth to fill up a byte (0x0A -> 0xAA)
  */
 
-png_uint_32 get_value (FILE *pnm_file, int depth)
+png_uint_32 get_pnm_value (FILE *pnm_file, int depth)
 {
   static png_uint_32 mask = 0;
-  char token[16];
-  unsigned long ul_ret_value;
   png_uint_32 ret_value;
-  int i = 0;
+  int i;
 
   if (mask == 0)
     for (i = 0; i < depth; i++)
       mask = (mask << 1) | 0x01;
 
-  get_token (pnm_file, token, sizeof (token));
-  sscanf (token, "%lu", &ul_ret_value);
-  ret_value = (png_uint_32) ul_ret_value;
+  if (fscan_pnm_uint_32 (pnm_file, &ret_value) != 1)
+  {
+    /* FIXME:
+     * signal the invalid numeric tokens or the premature end of file,
+     * instead of pretending to read zeroes
+     */
+    return 0;
+  }
 
   ret_value &= mask;
 
diff --git a/contrib/pngminus/png2pnm.bat b/contrib/pngminus/test_png2pnm.bat
old mode 100755
new mode 100644
similarity index 100%
rename from contrib/pngminus/png2pnm.bat
rename to contrib/pngminus/test_png2pnm.bat
diff --git a/contrib/pngminus/png2pnm.sh b/contrib/pngminus/test_png2pnm.sh
similarity index 100%
rename from contrib/pngminus/png2pnm.sh
rename to contrib/pngminus/test_png2pnm.sh
diff --git a/contrib/pngminus/pngminus.bat b/contrib/pngminus/test_pngminus.bat
similarity index 100%
rename from contrib/pngminus/pngminus.bat
rename to contrib/pngminus/test_pngminus.bat
diff --git a/contrib/pngminus/pngminus.sh b/contrib/pngminus/test_pngminus.sh
similarity index 100%
rename from contrib/pngminus/pngminus.sh
rename to contrib/pngminus/test_pngminus.sh
diff --git a/contrib/pngminus/pnm2png.bat b/contrib/pngminus/test_pnm2png.bat
old mode 100755
new mode 100644
similarity index 100%
rename from contrib/pngminus/pnm2png.bat
rename to contrib/pngminus/test_pnm2png.bat
diff --git a/contrib/pngminus/pnm2png.sh b/contrib/pngminus/test_pnm2png.sh
similarity index 100%
rename from contrib/pngminus/pnm2png.sh
rename to contrib/pngminus/test_pnm2png.sh
diff --git a/contrib/powerpc-vsx/linux.c b/contrib/powerpc-vsx/linux.c
index 32ed9d7..d861b28 100644
--- a/contrib/powerpc-vsx/linux.c
+++ b/contrib/powerpc-vsx/linux.c
@@ -2,7 +2,6 @@
  *
  * Copyright (c) 2017 Glenn Randers-Pehrson
  * Written by Vadim Barkov, 2017.
- * Last changed in libpng 1.6.29 [March 16, 2017]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -12,7 +11,7 @@
  * BUG REPORTS: png-mng-implement@sourceforge.net
  *
  * png_have_vsx implemented for Linux by reading the widely available
- * pseudo-file /proc/cpuinfo. 
+ * pseudo-file /proc/cpuinfo.
  *
  * This code is strict ANSI-C and is probably moderately portable; it does
  * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
diff --git a/contrib/powerpc-vsx/linux_aux.c b/contrib/powerpc-vsx/linux_aux.c
index 7828aca..6ec048e 100644
--- a/contrib/powerpc-vsx/linux_aux.c
+++ b/contrib/powerpc-vsx/linux_aux.c
@@ -2,7 +2,6 @@
  *
  * Copyright (c) 2017 Glenn Randers-Pehrson
  * Written by Vadim Barkov, 2017.
- * Last changed in libpng 1.6.29 [March 16, 2017]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
diff --git a/contrib/testpngs/badpal/regression-palette-8.png b/contrib/testpngs/badpal/regression-palette-8.png
new file mode 100644
index 0000000..dcb88b6
--- /dev/null
+++ b/contrib/testpngs/badpal/regression-palette-8.png
Binary files differ
diff --git a/contrib/testpngs/badpal/small-palette-1.png b/contrib/testpngs/badpal/small-palette-1.png
new file mode 100644
index 0000000..7e9dbfd
--- /dev/null
+++ b/contrib/testpngs/badpal/small-palette-1.png
Binary files differ
diff --git a/contrib/testpngs/badpal/small-palette-2.png b/contrib/testpngs/badpal/small-palette-2.png
new file mode 100644
index 0000000..6629164
--- /dev/null
+++ b/contrib/testpngs/badpal/small-palette-2.png
Binary files differ
diff --git a/contrib/testpngs/badpal/small-palette-4.png b/contrib/testpngs/badpal/small-palette-4.png
new file mode 100644
index 0000000..7401dc7
--- /dev/null
+++ b/contrib/testpngs/badpal/small-palette-4.png
Binary files differ
diff --git a/contrib/testpngs/badpal/small-palette-8.png b/contrib/testpngs/badpal/small-palette-8.png
new file mode 100644
index 0000000..a453387
--- /dev/null
+++ b/contrib/testpngs/badpal/small-palette-8.png
Binary files differ
diff --git a/contrib/testpngs/badpal/test-palette-1.png b/contrib/testpngs/badpal/test-palette-1.png
new file mode 100644
index 0000000..614fd97
--- /dev/null
+++ b/contrib/testpngs/badpal/test-palette-1.png
Binary files differ
diff --git a/contrib/testpngs/badpal/test-palette-2.png b/contrib/testpngs/badpal/test-palette-2.png
new file mode 100644
index 0000000..a7e9964
--- /dev/null
+++ b/contrib/testpngs/badpal/test-palette-2.png
Binary files differ
diff --git a/contrib/testpngs/badpal/test-palette-4.png b/contrib/testpngs/badpal/test-palette-4.png
new file mode 100644
index 0000000..39853bf
--- /dev/null
+++ b/contrib/testpngs/badpal/test-palette-4.png
Binary files differ
diff --git a/contrib/testpngs/badpal/test-palette-8.png b/contrib/testpngs/badpal/test-palette-8.png
new file mode 100644
index 0000000..46d0993
--- /dev/null
+++ b/contrib/testpngs/badpal/test-palette-8.png
Binary files differ
diff --git a/contrib/testpngs/makepngs.sh b/contrib/testpngs/makepngs.sh
index eb1c15f..f0238c3 100755
--- a/contrib/testpngs/makepngs.sh
+++ b/contrib/testpngs/makepngs.sh
@@ -1,12 +1,10 @@
-#!/bin/sh
-#
+#!/usr/bin/env bash
+
 # Make a set of test PNG files, MAKEPNG is the name of the makepng executable
 # built from contrib/libtests/makepng.c
 
 # Copyright (c) 2015 John Cunningham Bowler
 
-# Last changed in libpng 1.6.20 [December 3, 2015]
-
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
diff --git a/contrib/tools/checksum-icc.c b/contrib/tools/checksum-icc.c
index 581e708..83e1f9a 100644
--- a/contrib/tools/checksum-icc.c
+++ b/contrib/tools/checksum-icc.c
@@ -2,8 +2,6 @@
  *
  * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [February 14, 2013]
- *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
@@ -11,8 +9,8 @@
  * Generate crc32 and adler32 checksums of the given input files, used to
  * generate check-codes for use when matching ICC profiles within libpng.
  */
-#include <stdio.h>
 
+#include <stdio.h>
 #include <zlib.h>
 
 static int
diff --git a/contrib/tools/chkfmt b/contrib/tools/chkfmt.sh
similarity index 67%
rename from contrib/tools/chkfmt
rename to contrib/tools/chkfmt.sh
index 95181fd..8810aa7 100755
--- a/contrib/tools/chkfmt
+++ b/contrib/tools/chkfmt.sh
@@ -1,21 +1,28 @@
 #!/bin/sh
 
-# chkfmt
+# chkfmt.sh
 #
-# COPYRIGHT: Written by John Cunningham Bowler, 2010.
+# COPYRIGHT:
+# Written by John Cunningham Bowler, 2010.
+# Revised by Cosmin Truta, 2022.
 # To the extent possible under law, the author has waived all copyright and
-# related or neighboring rights to this work.  This work is published from:
-# United States.
+# related or neighboring rights to this work.  The author published this work
+# from the United States.
 #
-# Check the format of the source files in the current directory - checks for a
-# line length of 80 characters max and no tab characters.
+# Check the format of the source files in the current directory:
+#
+#  * The lines should not exceed a predefined maximum length.
+#  * Tab characters should appear only where necessary (e.g. in makefiles).
 #
 # Optionally arguments are files or directories to check.
 #
-# -v: output the long lines (makes fixing them easier)
-# -e: spawn an editor for each file that needs a change ($EDITOR must be
-#     defined).  When using -e the script MUST be run from an interactive
-#     command line.
+#  -v: output the long lines (makes fixing them easier)
+#  -e: spawn an editor for each file that needs a change ($EDITOR must be
+#      defined).  When using -e the script MUST be run from an interactive
+#      command line.
+
+script_name=`basename "$0"`
+
 verbose=
 edit=
 vers=
@@ -32,14 +39,14 @@
       # Copy the standard streams for the editor
       exec 3>&0 4>&1 5>&2
    else
-      echo "chkfmt -e: EDITOR must be defined" >&2
+      echo "$script_name -e: EDITOR must be defined" >&2
       exit 1
    fi
 }
 
 # Function to edit a single file - if the file isn't changed ask the user
-# whether or not to continue.  This stuff only works if the script is run from
-# the command line (otherwise, don't specify -e or you will be sorry).
+# whether or not to continue.  This stuff only works if the script is run
+# from the command line (otherwise, don't specify -e or you will be sorry).
 doed(){
    cp "$file" "$file".orig
    "$EDITOR" "$file" 0>&3 1>&4 2>&5 3>&- 4>&- 5>&- || exit 1
@@ -53,19 +60,22 @@
    return 0
 }
 
-# In beta versions the version string which appears in files can be a little
-# long and cause spuriously overlong lines.  To avoid this substitute the version
-# string with a 'standard' version a.b.cc before checking for long lines.
+# In beta versions, the version string which appears in files can be a little
+# long and cause spuriously overlong lines.  To avoid this, substitute the
+# version string with a placeholder string "a.b.cc" before checking for long
+# lines.
+# (Starting from libpng version 1.6.36, we switched to a conventional Git
+# workflow, and we are no longer publishing beta versions.)
 if test -r png.h
 then
    vers="`sed -n -e \
    's/^#define PNG_LIBPNG_VER_STRING .\([0-9]\.[0-9]\.[0-9][0-9a-z]*\).$/\1/p' \
    png.h`"
-   echo "chkfmt: checking version $vers"
+   echo "$script_name: checking version $vers"
 fi
 if test -z "$vers"
 then
-   echo "chkfmt: png.h not found, ignoring version number" >&2
+   echo "$script_name: png.h not found, ignoring version number" >&2
 fi
 
 test -n "$1" || set -- .
@@ -89,13 +99,16 @@
          check_tabs=
          line_length=100;;
       *.awk)
-         # Includes literal tabs
+         # Allow literal tabs.
          check_tabs=
-         # The following is arbitrary
+         # Mainframe line printer, anyone?
          line_length=132;;
+      */ci_*.sh)
+         check_tabs=yes
+         line_length=100;;
       *contrib/*/*.[ch])
          check_tabs=yes
-         line_length=96;;
+         line_length=100;;
       *)
          check_tabs=yes
          line_length=80;;
diff --git a/contrib/tools/cvtcolor.c b/contrib/tools/cvtcolor.c
index e6793c7..111dfce 100644
--- a/contrib/tools/cvtcolor.c
+++ b/contrib/tools/cvtcolor.c
@@ -1,7 +1,4 @@
-/*-
- * convert.c
- *
- * Last changed in libpng 1.6.0 [February 14, 2013]
+/* convert.c
  *
  * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
@@ -10,6 +7,7 @@
  *
  * Convert 8-bit sRGB or 16-bit linear values to another format.
  */
+
 #define _ISOC99_SOURCE 1
 
 #include <stdlib.h>
diff --git a/contrib/tools/genpng.c b/contrib/tools/genpng.c
index 0b3f981..c43bea9 100644
--- a/contrib/tools/genpng.c
+++ b/contrib/tools/genpng.c
@@ -1,4 +1,4 @@
-/*- genpng
+/* genpng
  *
  * COPYRIGHT: Written by John Cunningham Bowler, 2015.
  * Revised by Glenn Randers-Pehrson, 2017, to add buffer-size check.
@@ -69,6 +69,7 @@
  * joins are mitres; the outside of the lines are continued to the point of
  * intersection.
  */
+
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
@@ -453,7 +454,7 @@
  * { inside_circle_filled, check_circle_filled },
  * { inside_circle, check_circle }
  *
- * The functions here are analoguous to the square ones; however, they check
+ * The functions here are analogous to the square ones; however, they check
  * the corresponding ellipse as opposed to the rectangle.
  */
 static int
diff --git a/contrib/tools/intgamma.sh b/contrib/tools/intgamma.sh
index 41c5d6d..aaed68a 100755
--- a/contrib/tools/intgamma.sh
+++ b/contrib/tools/intgamma.sh
@@ -1,13 +1,11 @@
 #!/bin/sh
-#
+
 # intgamma.sh
 #
-# Last changed in libpng 1.6.0 [February 14, 2013]
-#
 # COPYRIGHT: Written by John Cunningham Bowler, 2013.
 # To the extent possible under law, the author has waived all copyright and
-# related or neighboring rights to this work.  This work is published from:
-# United States.
+# related or neighboring rights to this work.  The author published this work
+# from the United States.
 #
 # Shell script to generate png.c 8-bit and 16-bit log tables (see the code in
 # png.c for details).
@@ -17,11 +15,11 @@
 # (0..255) value and a similar table for the exponent calculation.
 #
 # "bc" must be on the path when the script is executed, and the math library
-# (-lm) must be available
-#
-# function to print out a list of numbers as integers; the function truncates
-# the integers which must be one-per-line
-function print(){
+# (-lm) must be available.
+
+# Function to print out a list of numbers as integers; the function truncates
+# the integers which must be one-per-line.
+print(){
    awk 'BEGIN{
       str = ""
    }
diff --git a/contrib/tools/makesRGB.c b/contrib/tools/makesRGB.c
index d0c0ca9..5ef3ddf 100644
--- a/contrib/tools/makesRGB.c
+++ b/contrib/tools/makesRGB.c
@@ -1,7 +1,5 @@
 /* makesRGB.c -- build sRGB-to-linear and linear-to-sRGB conversion tables
  *
- * Last changed in libpng 1.6.0 [February 14, 2013]
- *
  * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
@@ -14,6 +12,7 @@
  * approximation to the 8-bit sRGB encoded value.  Calculate the error in these
  * tables and display it.
  */
+
 #define _C99_SOURCE 1
 #include <stdio.h>
 #include <math.h>
diff --git a/contrib/tools/png-fix-itxt.c b/contrib/tools/png-fix-itxt.c
index c7654c1..b8286b9 100644
--- a/contrib/tools/png-fix-itxt.c
+++ b/contrib/tools/png-fix-itxt.c
@@ -1,8 +1,6 @@
-
-/* png-fix-itxt version 1.0.0
+/* png-fix-itxt
  *
  * Copyright 2015 Glenn Randers-Pehrson
- * Last changed in libpng 1.6.18 [July 23, 2015]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -10,7 +8,7 @@
  *
  * Usage:
  *
- *     png-fix-itxt.exe < bad.png > good.png
+ *     png-fix-itxt < bad.png > good.png
  *
  * Fixes a PNG file written with libpng-1.6.0 or 1.6.1 that has one or more
  * uncompressed iTXt chunks.  Assumes that the actual length is greater
diff --git a/contrib/tools/pngcp.c b/contrib/tools/pngcp.c
index 16d4e7f..cf621fa 100644
--- a/contrib/tools/pngcp.c
+++ b/contrib/tools/pngcp.c
@@ -1,8 +1,6 @@
 /* pngcp.c
  *
- * Copyright (c) 2016 John Cunningham Bowler
- *
- * Last changed in libpng 1.6.24 [August 4, 2016]
+ * Copyright (c) 2016,2022,2024 John Cunningham Bowler
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -14,7 +12,12 @@
  *
  * For a more extensive example that uses the transforms see
  * contrib/libtests/pngimage.c in the libpng distribution.
+ *
+ * This code is not intended for installation in a release system; the command
+ * line options are not documented and most of the behavior is intended for
+ * testing libpng performance, both speed and compression.
  */
+
 #include "pnglibconf.h" /* To find how libpng was configured. */
 
 #ifdef PNG_PNGCP_TIMING_SUPPORTED
@@ -85,16 +88,6 @@
 #  define voidcast(type, value) (value)
 #endif /* __cplusplus */
 
-#ifdef __GNUC__
-   /* Many versions of GCC erroneously report that local variables unmodified
-    * within the scope of a setjmp may be clobbered.  This hacks round the
-    * problem (sometimes) without harming other compilers.
-    */
-#  define gv volatile
-#else
-#  define gv
-#endif
-
 /* 'CLOCK_PROCESS_CPUTIME_ID' is one of the clock timers for clock_gettime.  It
  * need not be supported even when clock_gettime is available.  It returns the
  * 'CPU' time the process has consumed.  'CPU' time is assumed to include time
@@ -336,7 +329,7 @@
 #  define VLC(name) VLCIDAT(name) VLCiCCP(name) VLCzTXt(name)
 
 #  ifdef PNG_SW_COMPRESS_png_level
-      /* The libpng compression level isn't searched because it justs sets the
+      /* The libpng compression level isn't searched because it just sets the
        * other things that are searched!
        */
       VLO("compression", compression, 0)
@@ -392,6 +385,7 @@
 {
    jmp_buf          error_return;      /* Where to go to on error */
    unsigned int     errset;            /* error_return is set */
+   int              errlevel;          /* error level from longjmp */
 
    const char      *operation;         /* What is happening */
    const char      *filename;          /* The name of the original file */
@@ -503,10 +497,10 @@
 }
 
 static void
-display_clean_read(struct display *dp)
+display_clean_read(struct display *dp, int freeinfo)
 {
    if (dp->read_pp != NULL)
-      png_destroy_read_struct(&dp->read_pp, NULL, NULL);
+      png_destroy_read_struct(&dp->read_pp, freeinfo ? &dp->ip : NULL, NULL);
 
    if (dp->fp != NULL)
    {
@@ -517,7 +511,7 @@
 }
 
 static void
-display_clean_write(struct display *dp)
+display_clean_write(struct display *dp, int freeinfo)
 {
    if (dp->fp != NULL)
    {
@@ -527,14 +521,14 @@
    }
 
    if (dp->write_pp != NULL)
-      png_destroy_write_struct(&dp->write_pp, dp->tsp > 0 ? NULL : &dp->ip);
+      png_destroy_write_struct(&dp->write_pp, freeinfo ? &dp->ip : NULL);
 }
 
 static void
 display_clean(struct display *dp)
 {
-   display_clean_read(dp);
-   display_clean_write(dp);
+   display_clean_read(dp, 1/*freeinfo*/);
+   display_clean_write(dp, 1/*freeinfo*/);
    dp->output_file = NULL;
 
 #  if PNG_LIBPNG_VER < 10700 && defined PNG_TEXT_SUPPORTED
@@ -631,7 +625,10 @@
    if (level > APP_FAIL || (level > ERRORS && !(dp->options & CONTINUE)))
    {
       if (dp->errset)
+      {
+         dp->errlevel = level;
          longjmp(dp->error_return, level);
+      }
 
       else
          exit(99);
@@ -778,7 +775,7 @@
 set_opt_string(struct display *dp, unsigned int sp)
    /* Add the appropriate option string to dp->curr. */
 {
-   dp->stack[sp].opt_string_end = set_opt_string_(dp, sp, dp->stack[sp].opt, 
+   dp->stack[sp].opt_string_end = set_opt_string_(dp, sp, dp->stack[sp].opt,
       options[dp->stack[sp].opt].values[dp->stack[sp].entry].name);
 }
 
@@ -1745,7 +1742,17 @@
 static void
 read_png(struct display *dp, const char *filename)
 {
-   display_clean_read(dp); /* safety */
+   /* This is an assumption of the code; it may happen if a previous write fails
+    * and there is a bug in the cleanup handling below (look for setjmp).
+    * Passing freeinfo==1 to display_clean_read below avoids a second error
+    * on dp->ip != NULL below.
+    */
+   if (dp->read_pp != NULL)
+   {
+      display_log(dp, APP_FAIL, "unexpected png_read_struct");
+      display_clean_read(dp, 1/*freeinfo*/); /* recovery */
+   }
+
    display_start_read(dp, filename);
 
    dp->read_pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, dp,
@@ -1769,6 +1776,13 @@
          png_set_check_for_invalid_index(dp->read_pp, -1/*off completely*/);
 #  endif /* IGNORE_INDEX */
 
+   if (dp->ip != NULL)
+   {
+      /* UNEXPECTED: some problem in the display_clean function calls! */
+      display_log(dp, APP_FAIL, "read_png: freeing old info struct");
+      png_destroy_info_struct(dp->read_pp, &dp->ip);
+   }
+
    /* The png_read_png API requires us to make the info struct, but it does the
     * call to png_read_info.
     */
@@ -1848,7 +1862,14 @@
    }
 #endif /* FIX_INDEX */
 
-   display_clean_read(dp);
+   /* NOTE: dp->ip is where all the information about the PNG that was just read
+    * is stored.  It can be used to write and write again a single PNG file,
+    * however be aware that prior to libpng 1.7 text chunks could only be
+    * written once; this is a bug which would require a significant code rewrite
+    * to fix, it has been there in several versions of libpng (it was introduced
+    * to fix another bug involving duplicate writes of the text chunks.)
+    */
+   display_clean_read(dp, 0/*freeiinfo*/);
    dp->operation = "none";
 }
 
@@ -1975,7 +1996,21 @@
 static void
 write_png(struct display *dp, const char *destname)
 {
-   display_clean_write(dp); /* safety */
+   /* If this test fails png_write_png would fail *silently* below; this
+    * is not helpful, so catch the problem now and give up:
+    */
+   if (dp->ip == NULL)
+      display_log(dp, INTERNAL_ERROR, "missing png_info");
+
+   /* This is an assumption of the code; it may happen if a previous
+    * write fails and there is a bug in the cleanup handling below.
+    */
+   if (dp->write_pp != NULL)
+   {
+      display_log(dp, APP_FAIL, "unexpected png_write_struct");
+      display_clean_write(dp, 0/*!freeinfo*/);
+   }
+
    display_start_write(dp, destname);
 
    dp->write_pp = png_create_write_struct(PNG_LIBPNG_VER_STRING, dp,
@@ -2073,10 +2108,6 @@
                destname == NULL ? "stdout" : destname, strerror(errno));
    }
 
-   /* Clean it on the way out - if control returns to the caller then the
-    * written_file contains the required data.
-    */
-   display_clean_write(dp);
    dp->operation = "none";
 }
 
@@ -2243,6 +2274,10 @@
       /* Loop to find the best option. */
       do
       {
+         /* Clean before each write_png; this just removes *dp->write_pp which
+          * cannot be reused.
+          */
+         display_clean_write(dp, 0/*!freeinfo*/);
          write_png(dp, tmpname);
 
          /* And compare the sizes (the write function makes sure write_size
@@ -2272,17 +2307,14 @@
       /* Do this for the 'sizes' option so that it reports the correct size. */
       dp->write_size = dp->best_size;
    }
+
+   display_clean_write(dp, 1/*freeinfo*/);
 }
 
 static int
-cppng(struct display *dp, const char *file, const char *gv dest)
-   /* Exists solely to isolate the setjmp clobbers which some versions of GCC
-    * erroneously generate.
-    */
+cppng(struct display *dp, const char *file, const char *dest)
 {
-   int ret = setjmp(dp->error_return);
-
-   if (ret == 0)
+   if (setjmp(dp->error_return) == 0)
    {
       dp->errset = 1;
       cp_one_file(dp, file, dest);
@@ -2294,10 +2326,11 @@
    {
       dp->errset = 0;
 
-      if (ret < ERRORS) /* shouldn't longjmp on warnings */
-         display_log(dp, INTERNAL_ERROR, "unexpected return code %d", ret);
+      if (dp->errlevel < ERRORS) /* shouldn't longjmp on warnings */
+         display_log(dp, INTERNAL_ERROR, "unexpected return code %d",
+               dp->errlevel);
 
-      return ret;
+      return dp->errlevel;
    }
 }
 
diff --git a/contrib/tools/pngfix.c b/contrib/tools/pngfix.c
index 2fa5d13..8d5dc46 100644
--- a/contrib/tools/pngfix.c
+++ b/contrib/tools/pngfix.c
@@ -1,7 +1,6 @@
 /* pngfix.c
  *
- * Last changed in libpng 1.6.31 [July 27, 2017]
- * Copyright (c) 2014-2017 John Cunningham Bowler
+ * Copyright (c) 2014-2017,2024 John Cunningham Bowler
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -10,6 +9,7 @@
  * Tool to check and fix the zlib inflate 'too far back' problem.
  * See the usage message for more information.
  */
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -20,19 +20,6 @@
 
 #define implies(x,y) assert(!(x) || (y))
 
-#ifdef __GNUC__
-   /* This is used to fix the error:
-    *
-    * pngfix.c:
-    * In function 'zlib_advance':
-    * pngfix.c:181:13: error: assuming signed overflow does not
-    *   occur when simplifying conditional to constant [-Werror=strict-overflow]
-    */
-#  define FIX_GCC volatile
-#else
-#  define FIX_GCC
-#endif
-
 #define PROGRAM_NAME "pngfix"
 
 /* Define the following to use this program against your installed libpng,
@@ -146,11 +133,6 @@
 /* Is it safe to copy? */
 #define SAFE_TO_COPY(chunk) (((chunk) & PNG_U32(0,0,0,32)) != 0)
 
-/* Fix ups for builds with limited read support */
-#ifndef PNG_ERROR_TEXT_SUPPORTED
-#  define png_error(a,b) png_err(a)
-#endif
-
 /********************************* UTILITIES **********************************/
 /* UNREACHED is a value to cause an assert to fail. Because of the way the
  * assert macro is written the string "UNREACHED" is produced in the error
@@ -218,7 +200,7 @@
     * in_digits+1 if add is known to be in the range -65535..65535.
     */
 {
-   FIX_GCC int out_digits = 0;
+   int out_digits = 0;
 
    while (out_digits < in_digits)
    {
@@ -263,7 +245,7 @@
 }
 
 static int
-uarb_mult_digit(uarb acc, int a_digits, uarb num, FIX_GCC int n_digits,
+uarb_mult_digit(uarb acc, int a_digits, uarb num, int n_digits,
    png_uint_16 val)
    /* Primitive one-digit multiply - 'val' must be 0..65535. Note that this
     * primitive is a multiply and accumulate - the result of *num * val is added
@@ -336,7 +318,7 @@
     * 1..15
     */
 {
-   FIX_GCC int i = ndigits;
+   int i = ndigits;
    png_uint_16 carry = 0;
 
    assert(right_shift >= 1 && right_shift <= 15);
@@ -351,7 +333,7 @@
       inout[i] = temp;
 
       /* The shift may reduce ndigits */
-      if (i == ndigits-1 && temp == 0)
+      if (i+1 == ndigits && temp == 0)
          ndigits = i;
    }
 
@@ -867,7 +849,7 @@
     * signature (in length,type).
     *
     * When a chunk control structure is instantiated these values are copied
-    * into the structure and can then be overritten with the data for the next
+    * into the structure and can then be overwritten with the data for the next
     * chunk.
     */
    fpos_t         data_pos;      /* Position of first byte of chunk data */
@@ -1005,10 +987,18 @@
 
    if (file->out != NULL)
    {
-      /* NOTE: this is bitwise |, all the following functions must execute and
-       * must succeed.
+      /* On some systems 'fclose' deletes the FILE struct (making it
+       * inaccessbile).  There is no guarantee that fclose returns an error
+       * code from fflush or, indeed, from the FILE error indicator.  There is
+       * also no explicit (or clear) guarantee in the standard that anything
+       * other than a read or write operation sets the error indicator; fflush
+       * is not a read or write operation, so both conditions must be checked
+       * to ensure the close succeeded and in ANSI-C conformant code they must
+       * be checked before the fclose call.
        */
-      if (ferror(file->out) | fflush(file->out) | fclose(file->out))
+      const int err = fflush(file->out) || ferror(file->out);
+
+      if (fclose(file->out) || err)
       {
          perror(file->out_name);
          emit_error(file, READ_ERROR_CODE, "output write error");
@@ -1598,7 +1588,7 @@
    chunk->chunk_length = file->length;
    chunk->chunk_type = file->type;
 
-   /* Compresssed/uncompressed size information (from the zlib control structure
+   /* Compressed/uncompressed size information (from the zlib control structure
     * that is used to check the compressed data in a chunk.)
     */
    chunk->uncompressed_digits = 0;
@@ -2929,7 +2919,7 @@
    }
 
    /* Control reaches this point if the chunk must be skipped.  For chunks other
-    * than IDAT this means that the zlib compressed data is fatally damanged and
+    * than IDAT this means that the zlib compressed data is fatally damaged and
     * the chunk will not be passed to libpng.  For IDAT it means that the end of
     * the IDAT stream has not yet been reached and we must handle the next
     * (IDAT) chunk.  If the LZ data in an IDAT stream cannot be read 'stop' must
@@ -3961,6 +3951,14 @@
       {
          size_t outlen = strlen(*argv);
 
+         if (outlen > FILENAME_MAX)
+         {
+            fprintf(stderr, "%s: output file name too long: %s%s%s\n",
+               prog, prefix, *argv, suffix ? suffix : "");
+            global.status_code |= WRITE_ERROR;
+            continue;
+         }
+
          if (outfile == NULL) /* else this takes precedence */
          {
             /* Consider the prefix/suffix options */
@@ -4046,4 +4044,4 @@
    return 77;
 }
 #endif /* PNG_SETJMP_SUPPORTED */
-
+/* vi: set textwidth=80 shiftwidth=3 softtabstop=-1 expandtab: */
diff --git a/contrib/tools/reindent b/contrib/tools/reindent
deleted file mode 100755
index f4df309..0000000
--- a/contrib/tools/reindent
+++ /dev/null
@@ -1,25 +0,0 @@
-#!/bin/sh
-
-# reindent a libpng C source
-
-# COPYRIGHT: Written by Glenn Randers-Pehrson, 2016.
-# To the extent possible under law, the author has waived all copyright and
-# related or neighboring rights to this work.  This work is published from:
-# United States.
-
-# Usage:
-# reindent inputtabsize outputtabsize inputcontinuestring outputcontinuestring
-#
-# Assumes that continued lines begin with indentation plus one space, and
-# that continued comments begin with indentation plus " *".
-#
-# eg, to change libpng coding style from 3-space indentation with 4-space
-# continuations to 4-space indentation with 2-space continuations:
-#
-#  reindent 3 4 "\t " "  " < example.c > example.c_4_2
-# and to restore the file back to libpng coding style
-#  reindent 4 3 "  " "    " < example.c_4_2 > example.c_3_4
-
-unexpand --first-only --t $1 | \
-   sed -e "/^	*$3[^\*]/{s/$3/$4/}" | \
-   expand -t $2
diff --git a/contrib/tools/sRGB.h b/contrib/tools/sRGB.h
index d1ece51..7f6bdfc 100644
--- a/contrib/tools/sRGB.h
+++ b/contrib/tools/sRGB.h
@@ -1,7 +1,4 @@
-/*-
- * sRGB.h
- *
- * Last changed in libpng 1.6.0 [February 14, 2013]
+/* sRGB.h
  *
  * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
@@ -16,6 +13,7 @@
  * (in fact the source of the numbers is the wikipedia article at
  * https://en.wikipedia.org/wiki/SRGB).
  */
+
 static double
 sRGB_from_linear(double l)
 {
diff --git a/contrib/visupng/VisualPng.c b/contrib/visupng/VisualPng.c
index 6baa3b6..6f7b1df 100644
--- a/contrib/visupng/VisualPng.c
+++ b/contrib/visupng/VisualPng.c
@@ -103,7 +103,7 @@
         return 0;
     }
 
-    /* if filename given on commandline, store it */
+    /* if filename given on command line, store it */
     if ((szCmdLine != NULL) && (*szCmdLine != '\0'))
         if (szCmdLine[0] == '"')
             strncpy (szCmdFileName, szCmdLine + 1, strlen(szCmdLine) - 2);
diff --git a/depcomp b/depcomp
index 65cbf70..715e343 100755
--- a/depcomp
+++ b/depcomp
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1999-2018 Free Software Foundation, Inc.
+# Copyright (C) 1999-2021 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
diff --git a/example.c b/example.c
index 2e2afaa..3465fbb 100644
--- a/example.c
+++ b/example.c
@@ -3,7 +3,7 @@
 
 /* example.c - an example of using libpng
  *
- * Maintained 2018 Cosmin Truta
+ * Maintained 2018-2024 Cosmin Truta
  * Maintained 1998-2016 Glenn Randers-Pehrson
  * Maintained 1996-1997 Andreas Dilger
  * Written 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -125,6 +125,7 @@
                png_image_free(&image);
             else
                free(buffer);
+         }
       }
 
       /* Something went wrong reading or writing the image.  libpng stores a
@@ -258,9 +259,9 @@
       return 0;
 
    /* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
-    * Return nonzero (true) if they match.
+    * Return true if they match.
     */
-   return(!png_sig_cmp(buf, 0, PNG_BYTES_TO_CHECK));
+   return png_sig_cmp(buf, 0, PNG_BYTES_TO_CHECK) == 0;
 }
 
 /* Read a PNG file.  You may want to return an error code if the read
@@ -280,7 +281,7 @@
    FILE *fp;
 
    if ((fp = fopen(file_name, "rb")) == NULL)
-      return (ERROR);
+      return ERROR;
 
 #else no_open_file /* prototype 2 */
 void read_png(FILE *fp, int sig_read) /* File is already open */
@@ -303,7 +304,7 @@
    if (png_ptr == NULL)
    {
       fclose(fp);
-      return (ERROR);
+      return ERROR;
    }
 
    /* Allocate/initialize the memory for image information.  REQUIRED. */
@@ -312,7 +313,7 @@
    {
       fclose(fp);
       png_destroy_read_struct(&png_ptr, NULL, NULL);
-      return (ERROR);
+      return ERROR;
    }
 
    /* Set error handling if you are using the setjmp/longjmp method (this is
@@ -325,7 +326,7 @@
       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
       fclose(fp);
       /* If we get here, we had a problem reading the file. */
-      return (ERROR);
+      return ERROR;
    }
 
    /* One of the following I/O initialization methods is REQUIRED. */
@@ -584,7 +585,7 @@
    fclose(fp);
 
    /* That's it! */
-   return (OK);
+   return OK;
 }
 
 /* Progressively read a file */
@@ -603,18 +604,18 @@
    if (*png_ptr == NULL)
    {
       *info_ptr = NULL;
-      return (ERROR);
+      return ERROR;
    }
    *info_ptr = png_create_info_struct(png_ptr);
    if (*info_ptr == NULL)
    {
       png_destroy_read_struct(png_ptr, info_ptr, NULL);
-      return (ERROR);
+      return ERROR;
    }
    if (setjmp(png_jmpbuf((*png_ptr))))
    {
       png_destroy_read_struct(png_ptr, info_ptr, NULL);
-      return (ERROR);
+      return ERROR;
    }
 
    /* You will need to provide all three function callbacks,
@@ -631,7 +632,7 @@
     */
    png_set_progressive_read_fn(*png_ptr, (void *)stream_data,
        info_callback, row_callback, end_callback);
-   return (OK);
+   return OK;
 }
 
 int
@@ -642,7 +643,7 @@
    {
       /* Free the png_ptr and info_ptr memory on error. */
       png_destroy_read_struct(png_ptr, info_ptr, NULL);
-      return (ERROR);
+      return ERROR;
    }
 
    /* Give chunks of data as they arrive from the data stream
@@ -656,7 +657,7 @@
     * callback, if you aren't already displaying them there.
     */
    png_process_data(*png_ptr, *info_ptr, buffer, length);
-   return (OK);
+   return OK;
 }
 
 info_callback(png_structp png_ptr, png_infop info)
@@ -746,7 +747,7 @@
    /* Open the file */
    fp = fopen(file_name, "wb");
    if (fp == NULL)
-      return (ERROR);
+      return ERROR;
 
    /* Create and initialize the png_struct with the desired error handler
     * functions.  If you want to use the default stderr and longjump method,
@@ -759,7 +760,7 @@
    if (png_ptr == NULL)
    {
       fclose(fp);
-      return (ERROR);
+      return ERROR;
    }
 
    /* Allocate/initialize the image information data.  REQUIRED. */
@@ -768,7 +769,7 @@
    {
       fclose(fp);
       png_destroy_write_struct(&png_ptr,  NULL);
-      return (ERROR);
+      return ERROR;
    }
 
    /* Set up error handling.  REQUIRED if you aren't supplying your own
@@ -779,7 +780,7 @@
       /* If we get here, we had a problem writing the file. */
       fclose(fp);
       png_destroy_write_struct(&png_ptr, &info_ptr);
-      return (ERROR);
+      return ERROR;
    }
 
    /* One of the following I/O initialization functions is REQUIRED. */
@@ -1034,7 +1035,7 @@
    fclose(fp);
 
    /* That's it! */
-   return (OK);
+   return OK;
 }
 
 #endif /* if 0 */
diff --git a/install-sh b/install-sh
index 8175c64..7c56c9c 100755
--- a/install-sh
+++ b/install-sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 # install - install a program, script, or datafile
 
-scriptversion=2018-03-11.20; # UTC
+scriptversion=2023-11-23.18; # UTC
 
 # This originates from X11R5 (mit/util/scripts/install.sh), which was
 # later released in X11R6 (xc/config/util/install.sh) with the
@@ -69,6 +69,11 @@
 # Desired mode of installed file.
 mode=0755
 
+# Create dirs (including intermediate dirs) using mode 755.
+# This is like GNU 'install' as of coreutils 8.32 (2020).
+mkdir_umask=22
+
+backupsuffix=
 chgrpcmd=
 chmodcmd=$chmodprog
 chowncmd=
@@ -99,19 +104,29 @@
      --version  display version info and exit.
 
   -c            (ignored)
-  -C            install only if different (preserve the last data modification time)
+  -C            install only if different (preserve data modification time)
   -d            create directories instead of installing files.
   -g GROUP      $chgrpprog installed files to GROUP.
   -m MODE       $chmodprog installed files to MODE.
   -o USER       $chownprog installed files to USER.
+  -p            pass -p to $cpprog.
   -s            $stripprog installed files.
+  -S SUFFIX     attempt to back up existing files, with suffix SUFFIX.
   -t DIRECTORY  install into DIRECTORY.
   -T            report an error if DSTFILE is a directory.
 
 Environment variables override the default commands:
   CHGRPPROG CHMODPROG CHOWNPROG CMPPROG CPPROG MKDIRPROG MVPROG
   RMPROG STRIPPROG
-"
+
+By default, rm is invoked with -f; when overridden with RMPROG,
+it's up to you to specify -f if you want it.
+
+If -S is not specified, no backups are attempted.
+
+Report bugs to <bug-automake@gnu.org>.
+GNU Automake home page: <https://www.gnu.org/software/automake/>.
+General help using GNU software: <https://www.gnu.org/gethelp/>."
 
 while test $# -ne 0; do
   case $1 in
@@ -137,8 +152,13 @@
     -o) chowncmd="$chownprog $2"
         shift;;
 
+    -p) cpprog="$cpprog -p";;
+
     -s) stripcmd=$stripprog;;
 
+    -S) backupsuffix="$2"
+        shift;;
+
     -t)
         is_target_a_directory=always
         dst_arg=$2
@@ -255,6 +275,10 @@
     dstdir=$dst
     test -d "$dstdir"
     dstdir_status=$?
+    # Don't chown directories that already exist.
+    if test $dstdir_status = 0; then
+      chowncmd=""
+    fi
   else
 
     # Waiting for this to be detected by the "$cpprog $src $dsttmp" command
@@ -301,22 +325,6 @@
   if test $dstdir_status != 0; then
     case $posix_mkdir in
       '')
-        # Create intermediate dirs using mode 755 as modified by the umask.
-        # This is like FreeBSD 'install' as of 1997-10-28.
-        umask=`umask`
-        case $stripcmd.$umask in
-          # Optimize common cases.
-          *[2367][2367]) mkdir_umask=$umask;;
-          .*0[02][02] | .[02][02] | .[02]) mkdir_umask=22;;
-
-          *[0-7])
-            mkdir_umask=`expr $umask + 22 \
-              - $umask % 100 % 40 + $umask % 20 \
-              - $umask % 10 % 4 + $umask % 2
-            `;;
-          *) mkdir_umask=$umask,go-w;;
-        esac
-
         # With -d, create the new directory with the user-specified mode.
         # Otherwise, rely on $mkdir_umask.
         if test -n "$dir_arg"; then
@@ -326,52 +334,49 @@
         fi
 
         posix_mkdir=false
-        case $umask in
-          *[123567][0-7][0-7])
-            # POSIX mkdir -p sets u+wx bits regardless of umask, which
-            # is incompatible with FreeBSD 'install' when (umask & 300) != 0.
-            ;;
-          *)
-            # Note that $RANDOM variable is not portable (e.g. dash);  Use it
-            # here however when possible just to lower collision chance.
-            tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$
+	# The $RANDOM variable is not portable (e.g., dash).  Use it
+	# here however when possible just to lower collision chance.
+	tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$
 
-            trap 'ret=$?; rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir" 2>/dev/null; exit $ret' 0
+	trap '
+	  ret=$?
+	  rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir" 2>/dev/null
+	  exit $ret
+	' 0
 
-            # Because "mkdir -p" follows existing symlinks and we likely work
-            # directly in world-writeable /tmp, make sure that the '$tmpdir'
-            # directory is successfully created first before we actually test
-            # 'mkdir -p' feature.
-            if (umask $mkdir_umask &&
-                $mkdirprog $mkdir_mode "$tmpdir" &&
-                exec $mkdirprog $mkdir_mode -p -- "$tmpdir/a/b") >/dev/null 2>&1
-            then
-              if test -z "$dir_arg" || {
-                   # Check for POSIX incompatibilities with -m.
-                   # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
-                   # other-writable bit of parent directory when it shouldn't.
-                   # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
-                   test_tmpdir="$tmpdir/a"
-                   ls_ld_tmpdir=`ls -ld "$test_tmpdir"`
-                   case $ls_ld_tmpdir in
-                     d????-?r-*) different_mode=700;;
-                     d????-?--*) different_mode=755;;
-                     *) false;;
-                   esac &&
-                   $mkdirprog -m$different_mode -p -- "$test_tmpdir" && {
-                     ls_ld_tmpdir_1=`ls -ld "$test_tmpdir"`
-                     test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
-                   }
-                 }
-              then posix_mkdir=:
-              fi
-              rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir"
-            else
-              # Remove any dirs left behind by ancient mkdir implementations.
-              rmdir ./$mkdir_mode ./-p ./-- "$tmpdir" 2>/dev/null
-            fi
-            trap '' 0;;
-        esac;;
+	# Because "mkdir -p" follows existing symlinks and we likely work
+	# directly in world-writeable /tmp, make sure that the '$tmpdir'
+	# directory is successfully created first before we actually test
+	# 'mkdir -p'.
+	if (umask $mkdir_umask &&
+	    $mkdirprog $mkdir_mode "$tmpdir" &&
+	    exec $mkdirprog $mkdir_mode -p -- "$tmpdir/a/b") >/dev/null 2>&1
+	then
+	  if test -z "$dir_arg" || {
+	       # Check for POSIX incompatibilities with -m.
+	       # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
+	       # other-writable bit of parent directory when it shouldn't.
+	       # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
+	       test_tmpdir="$tmpdir/a"
+	       ls_ld_tmpdir=`ls -ld "$test_tmpdir"`
+	       case $ls_ld_tmpdir in
+		 d????-?r-*) different_mode=700;;
+		 d????-?--*) different_mode=755;;
+		 *) false;;
+	       esac &&
+	       $mkdirprog -m$different_mode -p -- "$test_tmpdir" && {
+		 ls_ld_tmpdir_1=`ls -ld "$test_tmpdir"`
+		 test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
+	       }
+	     }
+	  then posix_mkdir=:
+	  fi
+	  rmdir "$tmpdir/a/b" "$tmpdir/a" "$tmpdir"
+	else
+	  # Remove any dirs left behind by ancient mkdir implementations.
+	  rmdir ./$mkdir_mode ./-p ./-- "$tmpdir" 2>/dev/null
+	fi
+	trap '' 0;;
     esac
 
     if
@@ -382,7 +387,7 @@
     then :
     else
 
-      # The umask is ridiculous, or mkdir does not conform to POSIX,
+      # mkdir does not conform to POSIX,
       # or it failed possibly due to a race condition.  Create the
       # directory the slow way, step by step, checking for races as we go.
 
@@ -411,7 +416,7 @@
           prefixes=
         else
           if $posix_mkdir; then
-            (umask=$mkdir_umask &&
+            (umask $mkdir_umask &&
              $doit_exec $mkdirprog $mkdir_mode -p -- "$dstdir") && break
             # Don't fail if two instances are running concurrently.
             test -d "$prefix" || exit 1
@@ -451,7 +456,18 @@
     trap 'ret=$?; rm -f "$dsttmp" "$rmtmp" && exit $ret' 0
 
     # Copy the file name to the temp name.
-    (umask $cp_umask && $doit_exec $cpprog "$src" "$dsttmp") &&
+    (umask $cp_umask &&
+     { test -z "$stripcmd" || {
+	 # Create $dsttmp read-write so that cp doesn't create it read-only,
+	 # which would cause strip to fail.
+	 if test -z "$doit"; then
+	   : >"$dsttmp" # No need to fork-exec 'touch'.
+	 else
+	   $doit touch "$dsttmp"
+	 fi
+       }
+     } &&
+     $doit_exec $cpprog "$src" "$dsttmp") &&
 
     # and set any options; do chmod last to preserve setuid bits.
     #
@@ -477,6 +493,13 @@
     then
       rm -f "$dsttmp"
     else
+      # If $backupsuffix is set, and the file being installed
+      # already exists, attempt a backup.  Don't worry if it fails,
+      # e.g., if mv doesn't support -f.
+      if test -n "$backupsuffix" && test -f "$dst"; then
+        $doit $mvcmd -f "$dst" "$dst$backupsuffix" 2>/dev/null
+      fi
+
       # Rename the file to the real destination.
       $doit $mvcmd -f "$dsttmp" "$dst" 2>/dev/null ||
 
@@ -491,9 +514,9 @@
         # file should still install successfully.
         {
           test ! -f "$dst" ||
-          $doit $rmcmd -f "$dst" 2>/dev/null ||
+          $doit $rmcmd "$dst" 2>/dev/null ||
           { $doit $mvcmd -f "$dst" "$rmtmp" 2>/dev/null &&
-            { $doit $rmcmd -f "$rmtmp" 2>/dev/null; :; }
+            { $doit $rmcmd "$rmtmp" 2>/dev/null; :; }
           } ||
           { echo "$0: cannot unlink or rename $dst" >&2
             (exit 1); exit 1
diff --git a/intel/filter_sse2_intrinsics.c b/intel/filter_sse2_intrinsics.c
index f52aaa8..d3c0fe9 100644
--- a/intel/filter_sse2_intrinsics.c
+++ b/intel/filter_sse2_intrinsics.c
@@ -259,7 +259,7 @@
       a = d; d = _mm_unpacklo_epi8(load4(row ), zero);
 
       /* (p-a) == (a+b-c - a) == (b-c) */
-   
+
       pa = _mm_sub_epi16(b,c);
 
       /* (p-b) == (a+b-c - b) == (a-c) */
diff --git a/libpng-manual.txt b/libpng-manual.txt
index 5dad92f..eb24ef4 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2024 Cosmin Truta
  Copyright (c) 1998-2018 Glenn Randers-Pehrson
 
  This document is released under the libpng license.
@@ -9,9 +9,9 @@
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.37 - April 2019
+ libpng version 1.6.36, December 2018, through 1.6.42 - January 2024
  Updated and distributed by Cosmin Truta
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2024 Cosmin Truta
 
  libpng versions 0.97, January 1998, through 1.6.35 - July 2018
  Updated and distributed by Glenn Randers-Pehrson
@@ -357,7 +357,7 @@
        return ERROR;
     }
 
-    is_png = !png_sig_cmp(header, 0, number);
+    is_png = (png_sig_cmp(header, 0, number) == 0);
     if (!is_png)
     {
        return NOT_PNG;
@@ -385,8 +385,7 @@
 
     if (!info_ptr)
     {
-       png_destroy_read_struct(&png_ptr,
-           (png_infopp)NULL, (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, NULL, NULL);
        return ERROR;
     }
 
@@ -419,14 +418,13 @@
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           &end_info);
+       png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
        fclose(fp);
        return ERROR;
     }
 
-Pass (png_infopp)NULL instead of &end_info if you didn't create
-an end_info structure.
+Pass NULL instead of &end_info if you didn't create an end_info
+structure.
 
 If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
@@ -496,7 +494,7 @@
 input stream. You must supply the function
 
     read_chunk_callback(png_structp png_ptr,
-         png_unknown_chunkp chunk);
+         png_unknown_chunkp chunk)
     {
        /* The unknown chunk structure contains your
           chunk data, along with similar data for any other
@@ -547,9 +545,9 @@
 You must supply a function
 
     void read_row_callback(png_structp png_ptr,
-       png_uint_32 row, int pass);
+       png_uint_32 row, int pass)
     {
-      /* put your code here */
+       /* put your code here */
     }
 
 (You can give it another name that you like instead of "read_row_callback")
@@ -877,7 +875,7 @@
 color channels). Note that PNG files always contain non-associated color
 channels; png_set_alpha_mode() with one of the modes causes the decoder to
 convert the pixels to an associated form before returning them to your
-application. 
+application.
 
 Since it is not necessary to perform arithmetic on opaque color values so
 long as they are not to be resampled and are in the final color space it is
@@ -1181,21 +1179,21 @@
 row_pointers prior to calling png_read_png() with
 
    if (height > PNG_UINT_32_MAX/(sizeof (png_byte)))
-      png_error (png_ptr,
+      png_error(png_ptr,
           "Image is too tall to process in memory");
 
    if (width > PNG_UINT_32_MAX/pixel_size)
-      png_error (png_ptr,
+      png_error(png_ptr,
           "Image is too wide to process in memory");
 
    row_pointers = png_malloc(png_ptr,
        height*(sizeof (png_bytep)));
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=NULL;  /* security precaution */
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = NULL;  /* security precaution */
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=png_malloc(png_ptr,
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = png_malloc(png_ptr,
           width*pixel_size);
 
    png_set_rows(png_ptr, info_ptr, &row_pointers);
@@ -1205,14 +1203,14 @@
 be sure that your platform is able to allocate such a large buffer:
 
    /* Guard against integer overflow */
-   if (height > PNG_SIZE_MAX/(width*pixel_size)) {
-        png_error(png_ptr,"image_data buffer would be too large");
-   }
+   if (height > PNG_SIZE_MAX/(width*pixel_size))
+      png_error(png_ptr, "image_data buffer would be too large");
 
-   png_bytep buffer=png_malloc(png_ptr,height*width*pixel_size);
+   png_bytep buffer = png_malloc(png_ptr,
+      height*width*pixel_size);
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=buffer+i*width*pixel_size;
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = buffer + i*width*pixel_size;
 
    png_set_rows(png_ptr, info_ptr, &row_pointers);
 
@@ -1465,25 +1463,24 @@
                      non-paletted images (PNG_INFO_tRNS)
 
     png_get_eXIf_1(png_ptr, info_ptr, &num_exif, &exif);
-                     (PNG_INFO_eXIf)
 
     exif           - Exif profile (array of png_byte)
+                     (PNG_INFO_eXIf)
 
     png_get_hIST(png_ptr, info_ptr, &hist);
-                     (PNG_INFO_hIST)
 
     hist           - histogram of palette (array of
-                     png_uint_16)
+                     png_uint_16) (PNG_INFO_hIST)
 
     png_get_tIME(png_ptr, info_ptr, &mod_time);
 
     mod_time       - time image was last modified
-                    (PNG_VALID_tIME)
+                     (PNG_INFO_tIME)
 
     png_get_bKGD(png_ptr, info_ptr, &background);
 
     background     - background color (of type
-                     png_color_16p) (PNG_VALID_bKGD)
+                     png_color_16p) (PNG_INFO_bKGD)
                      valid 16-bit red, green and blue
                      values, regardless of color_type
 
@@ -1743,13 +1740,13 @@
 viewing application that wishes to treat all images in the same way.
 
     if (color_type == PNG_COLOR_TYPE_PALETTE)
-        png_set_palette_to_rgb(png_ptr);
+       png_set_palette_to_rgb(png_ptr);
 
-    if (png_get_valid(png_ptr, info_ptr,
-        PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+       png_set_tRNS_to_alpha(png_ptr);
 
-    if (color_type == PNG_COLOR_TYPE_GRAY &&
-        bit_depth < 8) png_set_expand_gray_1_2_4_to_8(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+       png_set_expand_gray_1_2_4_to_8(png_ptr);
 
 The first two functions are actually aliases for png_set_expand(), added
 in libpng version 1.0.4, with the function names expanded to improve code
@@ -1764,18 +1761,20 @@
 Use this when the output color or gray channels are made linear to avoid fairly
 severe accuracy loss.
 
-   if (bit_depth < 16)
-      png_set_expand_16(png_ptr);
+    if (bit_depth < 16)
+       png_set_expand_16(png_ptr);
 
 PNG can have files with 16 bits per channel.  If you only can handle
 8 bits per channel, this will strip the pixels down to 8-bit.
 
     if (bit_depth == 16)
+    {
 #if PNG_LIBPNG_VER >= 10504
        png_set_scale_16(png_ptr);
 #else
        png_set_strip_16(png_ptr);
 #endif
+    }
 
 (The more accurate "png_set_scale_16()" API became available in libpng version
 1.5.4).
@@ -1792,7 +1791,7 @@
 version with no alpha channel use png_set_background; see below.
 
 As of libpng version 1.5.2, almost all useful expansions are supported, the
-major ommissions are conversion of grayscale to indexed images (which can be
+major omissions are conversion of grayscale to indexed images (which can be
 done trivially in the application) and conversion of indexed to grayscale (which
 can be done by a trivial manipulation of the palette.)
 
@@ -1901,7 +1900,7 @@
 to do that, you can add a true alpha channel with
 
     if (color_type == PNG_COLOR_TYPE_RGB ||
-       color_type == PNG_COLOR_TYPE_GRAY)
+        color_type == PNG_COLOR_TYPE_GRAY)
        png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
 
 where "filler" contains the alpha value to assign to each pixel.
@@ -1926,7 +1925,7 @@
     if (color_type == PNG_COLOR_TYPE_RGB ||
         color_type == PNG_COLOR_TYPE_RGB_ALPHA)
        png_set_rgb_to_gray(png_ptr, error_action,
-          double red_weight, double green_weight);
+          (double)red_weight, (double)green_weight);
 
     error_action = 1: silently do the conversion
 
@@ -1949,8 +1948,8 @@
 simply scaled by 100,000:
 
     png_set_rgb_to_gray(png_ptr, error_action,
-       png_fixed_point red_weight,
-       png_fixed_point green_weight);
+       (png_fixed_point)red_weight,
+       (png_fixed_point)green_weight);
 
 If you have set error_action = 1 or 2, you can
 later check whether the image really was gray, after processing
@@ -2186,9 +2185,8 @@
 a multiple-row buffer:
 
    /* Guard against integer overflow */
-   if (number_of_rows > PNG_SIZE_MAX/(width*pixel_size)) {
-        png_error(png_ptr,"image_data buffer would be too large");
-   }
+   if (number_of_rows > PNG_SIZE_MAX/(width*pixel_size))
+      png_error(png_ptr, "image_data buffer would be too large");
 
 Remember: Before you call png_read_update_info(), the png_get_*()
 functions return the values corresponding to the original PNG image.
@@ -2408,12 +2406,11 @@
 
     if (!end_info)
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
-   png_read_end(png_ptr, end_info);
+    png_read_end(png_ptr, end_info);
 
 If you are not interested, you should still call png_read_end()
 but you can pass NULL, avoiding the need to create an end_info structure.
@@ -2421,7 +2418,7 @@
 skipping over them and perhaps (depending on whether you have called
 png_set_crc_action) checking their CRCs while looking for the IEND chunk.
 
-   png_read_end(png_ptr, (png_infop)NULL);
+   png_read_end(png_ptr, NULL);
 
 If you don't call png_read_end(), then your file pointer will be
 left pointing to the first chunk after the last IDAT, which is probably
@@ -2430,13 +2427,11 @@
 
 When you are done, you can free all memory allocated by libpng like this:
 
-   png_destroy_read_struct(&png_ptr, &info_ptr,
-       &end_info);
+   png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
 
 or, if you didn't create an end_info structure,
 
-   png_destroy_read_struct(&png_ptr, &info_ptr,
-       (png_infopp)NULL);
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
 
 It is also possible to individually free the info_ptr members that
 point to libpng-allocated storage with the following function:
@@ -2556,15 +2551,13 @@
 
     if (!info_ptr)
     {
-       png_destroy_read_struct(&png_ptr,
-          (png_infopp)NULL, (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, NULL, NULL);
        return ERROR;
     }
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-          (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
@@ -2597,8 +2590,7 @@
  {
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
@@ -2763,8 +2755,7 @@
     png_infop info_ptr = png_create_info_struct(png_ptr);
     if (!info_ptr)
     {
-       png_destroy_write_struct(&png_ptr,
-           (png_infopp)NULL);
+       png_destroy_write_struct(&png_ptr, NULL);
        return ERROR;
     }
 
@@ -2790,7 +2781,7 @@
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-    png_destroy_write_struct(&png_ptr, &info_ptr);
+       png_destroy_write_struct(&png_ptr, &info_ptr);
        fclose(fp);
        return ERROR;
     }
@@ -2844,9 +2835,9 @@
 You must supply a function
 
     void write_row_callback(png_structp png_ptr, png_uint_32 row,
-       int pass);
+       int pass)
     {
-      /* put your code here */
+       /* put your code here */
     }
 
 (You can give it another name that you like instead of "write_row_callback")
@@ -3116,8 +3107,8 @@
 
     png_set_eXIf_1(png_ptr, info_ptr, num_exif, exif);
 
-    exif           - Exif profile (array of
-                     png_byte) (PNG_INFO_eXIf)
+    exif           - Exif profile (array of png_byte)
+                     (PNG_INFO_eXIf)
 
     png_set_hIST(png_ptr, info_ptr, hist);
 
@@ -3127,12 +3118,12 @@
     png_set_tIME(png_ptr, info_ptr, mod_time);
 
     mod_time       - time image was last modified
-                     (PNG_VALID_tIME)
+                     (PNG_INFO_tIME)
 
     png_set_bKGD(png_ptr, info_ptr, background);
 
     background     - background color (of type
-                     png_color_16p) (PNG_VALID_bKGD)
+                     png_color_16p) (PNG_INFO_bKGD)
 
     png_set_text(png_ptr, info_ptr, text_ptr, num_text);
 
@@ -4218,7 +4209,7 @@
 own functions as described above.  These functions also provide a void
 pointer that can be retrieved via
 
-    mem_ptr=png_get_mem_ptr(png_ptr);
+    mem_ptr = png_get_mem_ptr(png_ptr);
 
 Your replacement memory functions must have prototypes as follows:
 
@@ -4515,7 +4506,7 @@
 can still use PNG_DEBUG to control your own debugging:
 
    #ifdef PNG_DEBUG
-       fprintf(stderr, ...
+       fprintf(stderr, ...);
    #endif
 
 When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
@@ -4692,7 +4683,7 @@
 The function
     png_check_sig(sig, num)
 was replaced with
-    !png_sig_cmp(sig, 0, num)
+    png_sig_cmp(sig, 0, num) == 0
 It has been deprecated since libpng-0.90.
 
 The function
@@ -4756,8 +4747,8 @@
 png_set_asm_flags(), and png_mmx_supported()
 
 We removed the obsolete png_check_sig(), png_memcpy_check(), and
-png_memset_check() functions.  Instead use !png_sig_cmp(), memcpy(),
-and memset(), respectively.
+png_memset_check() functions.  Instead use png_sig_cmp() == 0,
+memcpy(), and memset(), respectively.
 
 The function png_set_gray_1_2_4_to_8() was removed. It has been
 deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with
@@ -5239,7 +5230,7 @@
 best choice for use in configure scripts for detecting the presence of any
 libpng version since 0.88.  In an autoconf "configure.in" you could use
 
-    AC_CHECK_LIB(png, png_get_io_ptr, ...
+    AC_CHECK_LIB(png, png_get_io_ptr, ...)
 
 XV. Source code repository
 
@@ -5248,12 +5239,12 @@
 going back to version 0.70.  You can access the git repository (read only)
 at
 
-    https://github.com/glennrp/libpng or
+    https://github.com/pnggroup/libpng or
     https://git.code.sf.net/p/libpng/code.git
 
 or you can browse it with a web browser at
 
-    https://github.com/glennrp/libpng or
+    https://github.com/pnggroup/libpng or
     https://sourceforge.net/p/libpng/code/ci/libpng16/tree/
 
 Patches can be sent to png-mng-implement at lists.sourceforge.net or
@@ -5263,7 +5254,7 @@
 
 or as a "pull request" to
 
-    https://github.com/glennrp/libpng/pulls
+    https://github.com/pnggroup/libpng/pulls
 
 We also accept patches built from the tar or zip distributions, and
 simple verbal descriptions of bug fixes, reported either to the
diff --git a/libpng.3 b/libpng.3
index f374235..57d06f2 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "April 14, 2019"
+.TH LIBPNG 3 "January 29, 2024"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.37
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.42
 
 .SH SYNOPSIS
 \fB#include <png.h>\fP
@@ -519,7 +519,7 @@
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2024 Cosmin Truta
  Copyright (c) 1998-2018 Glenn Randers-Pehrson
 
  This document is released under the libpng license.
@@ -528,9 +528,9 @@
 
  Based on:
 
- libpng version 1.6.36, December 2018, through 1.6.37 - April 2019
+ libpng version 1.6.36, December 2018, through 1.6.42 - January 2024
  Updated and distributed by Cosmin Truta
- Copyright (c) 2018-2019 Cosmin Truta
+ Copyright (c) 2018-2024 Cosmin Truta
 
  libpng versions 0.97, January 1998, through 1.6.35 - July 2018
  Updated and distributed by Glenn Randers-Pehrson
@@ -876,7 +876,7 @@
        return ERROR;
     }
 
-    is_png = !png_sig_cmp(header, 0, number);
+    is_png = (png_sig_cmp(header, 0, number) == 0);
     if (!is_png)
     {
        return NOT_PNG;
@@ -904,8 +904,7 @@
 
     if (!info_ptr)
     {
-       png_destroy_read_struct(&png_ptr,
-           (png_infopp)NULL, (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, NULL, NULL);
        return ERROR;
     }
 
@@ -938,14 +937,13 @@
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           &end_info);
+       png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
        fclose(fp);
        return ERROR;
     }
 
-Pass (png_infopp)NULL instead of &end_info if you didn't create
-an end_info structure.
+Pass NULL instead of &end_info if you didn't create an end_info
+structure.
 
 If you would rather avoid the complexity of setjmp/longjmp issues,
 you can compile libpng with PNG_NO_SETJMP, in which case
@@ -1015,7 +1013,7 @@
 input stream. You must supply the function
 
     read_chunk_callback(png_structp png_ptr,
-         png_unknown_chunkp chunk);
+         png_unknown_chunkp chunk)
     {
        /* The unknown chunk structure contains your
           chunk data, along with similar data for any other
@@ -1066,9 +1064,9 @@
 You must supply a function
 
     void read_row_callback(png_structp png_ptr,
-       png_uint_32 row, int pass);
+       png_uint_32 row, int pass)
     {
-      /* put your code here */
+       /* put your code here */
     }
 
 (You can give it another name that you like instead of "read_row_callback")
@@ -1396,7 +1394,7 @@
 color channels). Note that PNG files always contain non-associated color
 channels; png_set_alpha_mode() with one of the modes causes the decoder to
 convert the pixels to an associated form before returning them to your
-application. 
+application.
 
 Since it is not necessary to perform arithmetic on opaque color values so
 long as they are not to be resampled and are in the final color space it is
@@ -1700,21 +1698,21 @@
 row_pointers prior to calling png_read_png() with
 
    if (height > PNG_UINT_32_MAX/(sizeof (png_byte)))
-      png_error (png_ptr,
+      png_error(png_ptr,
           "Image is too tall to process in memory");
 
    if (width > PNG_UINT_32_MAX/pixel_size)
-      png_error (png_ptr,
+      png_error(png_ptr,
           "Image is too wide to process in memory");
 
    row_pointers = png_malloc(png_ptr,
        height*(sizeof (png_bytep)));
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=NULL;  /* security precaution */
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = NULL;  /* security precaution */
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=png_malloc(png_ptr,
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = png_malloc(png_ptr,
           width*pixel_size);
 
    png_set_rows(png_ptr, info_ptr, &row_pointers);
@@ -1724,14 +1722,14 @@
 be sure that your platform is able to allocate such a large buffer:
 
    /* Guard against integer overflow */
-   if (height > PNG_SIZE_MAX/(width*pixel_size)) {
-        png_error(png_ptr,"image_data buffer would be too large");
-   }
+   if (height > PNG_SIZE_MAX/(width*pixel_size))
+      png_error(png_ptr, "image_data buffer would be too large");
 
-   png_bytep buffer=png_malloc(png_ptr,height*width*pixel_size);
+   png_bytep buffer = png_malloc(png_ptr,
+      height*width*pixel_size);
 
-   for (int i=0; i<height, i++)
-      row_pointers[i]=buffer+i*width*pixel_size;
+   for (int i = 0; i < height, i++)
+      row_pointers[i] = buffer + i*width*pixel_size;
 
    png_set_rows(png_ptr, info_ptr, &row_pointers);
 
@@ -1984,25 +1982,24 @@
                      non-paletted images (PNG_INFO_tRNS)
 
     png_get_eXIf_1(png_ptr, info_ptr, &num_exif, &exif);
-                     (PNG_INFO_eXIf)
 
     exif           - Exif profile (array of png_byte)
+                     (PNG_INFO_eXIf)
 
     png_get_hIST(png_ptr, info_ptr, &hist);
-                     (PNG_INFO_hIST)
 
     hist           - histogram of palette (array of
-                     png_uint_16)
+                     png_uint_16) (PNG_INFO_hIST)
 
     png_get_tIME(png_ptr, info_ptr, &mod_time);
 
     mod_time       - time image was last modified
-                    (PNG_VALID_tIME)
+                     (PNG_INFO_tIME)
 
     png_get_bKGD(png_ptr, info_ptr, &background);
 
     background     - background color (of type
-                     png_color_16p) (PNG_VALID_bKGD)
+                     png_color_16p) (PNG_INFO_bKGD)
                      valid 16-bit red, green and blue
                      values, regardless of color_type
 
@@ -2262,13 +2259,13 @@
 viewing application that wishes to treat all images in the same way.
 
     if (color_type == PNG_COLOR_TYPE_PALETTE)
-        png_set_palette_to_rgb(png_ptr);
+       png_set_palette_to_rgb(png_ptr);
 
-    if (png_get_valid(png_ptr, info_ptr,
-        PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+       png_set_tRNS_to_alpha(png_ptr);
 
-    if (color_type == PNG_COLOR_TYPE_GRAY &&
-        bit_depth < 8) png_set_expand_gray_1_2_4_to_8(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+       png_set_expand_gray_1_2_4_to_8(png_ptr);
 
 The first two functions are actually aliases for png_set_expand(), added
 in libpng version 1.0.4, with the function names expanded to improve code
@@ -2283,18 +2280,20 @@
 Use this when the output color or gray channels are made linear to avoid fairly
 severe accuracy loss.
 
-   if (bit_depth < 16)
-      png_set_expand_16(png_ptr);
+    if (bit_depth < 16)
+       png_set_expand_16(png_ptr);
 
 PNG can have files with 16 bits per channel.  If you only can handle
 8 bits per channel, this will strip the pixels down to 8-bit.
 
     if (bit_depth == 16)
+    {
 #if PNG_LIBPNG_VER >= 10504
        png_set_scale_16(png_ptr);
 #else
        png_set_strip_16(png_ptr);
 #endif
+    }
 
 (The more accurate "png_set_scale_16()" API became available in libpng version
 1.5.4).
@@ -2311,7 +2310,7 @@
 version with no alpha channel use png_set_background; see below.
 
 As of libpng version 1.5.2, almost all useful expansions are supported, the
-major ommissions are conversion of grayscale to indexed images (which can be
+major omissions are conversion of grayscale to indexed images (which can be
 done trivially in the application) and conversion of indexed to grayscale (which
 can be done by a trivial manipulation of the palette.)
 
@@ -2420,7 +2419,7 @@
 to do that, you can add a true alpha channel with
 
     if (color_type == PNG_COLOR_TYPE_RGB ||
-       color_type == PNG_COLOR_TYPE_GRAY)
+        color_type == PNG_COLOR_TYPE_GRAY)
        png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
 
 where "filler" contains the alpha value to assign to each pixel.
@@ -2445,7 +2444,7 @@
     if (color_type == PNG_COLOR_TYPE_RGB ||
         color_type == PNG_COLOR_TYPE_RGB_ALPHA)
        png_set_rgb_to_gray(png_ptr, error_action,
-          double red_weight, double green_weight);
+          (double)red_weight, (double)green_weight);
 
     error_action = 1: silently do the conversion
 
@@ -2468,8 +2467,8 @@
 simply scaled by 100,000:
 
     png_set_rgb_to_gray(png_ptr, error_action,
-       png_fixed_point red_weight,
-       png_fixed_point green_weight);
+       (png_fixed_point)red_weight,
+       (png_fixed_point)green_weight);
 
 If you have set error_action = 1 or 2, you can
 later check whether the image really was gray, after processing
@@ -2705,9 +2704,8 @@
 a multiple-row buffer:
 
    /* Guard against integer overflow */
-   if (number_of_rows > PNG_SIZE_MAX/(width*pixel_size)) {
-        png_error(png_ptr,"image_data buffer would be too large");
-   }
+   if (number_of_rows > PNG_SIZE_MAX/(width*pixel_size))
+      png_error(png_ptr, "image_data buffer would be too large");
 
 Remember: Before you call png_read_update_info(), the png_get_*()
 functions return the values corresponding to the original PNG image.
@@ -2927,12 +2925,11 @@
 
     if (!end_info)
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
-   png_read_end(png_ptr, end_info);
+    png_read_end(png_ptr, end_info);
 
 If you are not interested, you should still call png_read_end()
 but you can pass NULL, avoiding the need to create an end_info structure.
@@ -2940,7 +2937,7 @@
 skipping over them and perhaps (depending on whether you have called
 png_set_crc_action) checking their CRCs while looking for the IEND chunk.
 
-   png_read_end(png_ptr, (png_infop)NULL);
+   png_read_end(png_ptr, NULL);
 
 If you don't call png_read_end(), then your file pointer will be
 left pointing to the first chunk after the last IDAT, which is probably
@@ -2949,13 +2946,11 @@
 
 When you are done, you can free all memory allocated by libpng like this:
 
-   png_destroy_read_struct(&png_ptr, &info_ptr,
-       &end_info);
+   png_destroy_read_struct(&png_ptr, &info_ptr, &end_info);
 
 or, if you didn't create an end_info structure,
 
-   png_destroy_read_struct(&png_ptr, &info_ptr,
-       (png_infopp)NULL);
+   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
 
 It is also possible to individually free the info_ptr members that
 point to libpng-allocated storage with the following function:
@@ -3075,15 +3070,13 @@
 
     if (!info_ptr)
     {
-       png_destroy_read_struct(&png_ptr,
-          (png_infopp)NULL, (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, NULL, NULL);
        return ERROR;
     }
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-          (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
@@ -3116,8 +3109,7 @@
  {
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-       png_destroy_read_struct(&png_ptr, &info_ptr,
-           (png_infopp)NULL);
+       png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
        return ERROR;
     }
 
@@ -3282,8 +3274,7 @@
     png_infop info_ptr = png_create_info_struct(png_ptr);
     if (!info_ptr)
     {
-       png_destroy_write_struct(&png_ptr,
-           (png_infopp)NULL);
+       png_destroy_write_struct(&png_ptr, NULL);
        return ERROR;
     }
 
@@ -3309,7 +3300,7 @@
 
     if (setjmp(png_jmpbuf(png_ptr)))
     {
-    png_destroy_write_struct(&png_ptr, &info_ptr);
+       png_destroy_write_struct(&png_ptr, &info_ptr);
        fclose(fp);
        return ERROR;
     }
@@ -3363,9 +3354,9 @@
 You must supply a function
 
     void write_row_callback(png_structp png_ptr, png_uint_32 row,
-       int pass);
+       int pass)
     {
-      /* put your code here */
+       /* put your code here */
     }
 
 (You can give it another name that you like instead of "write_row_callback")
@@ -3635,8 +3626,8 @@
 
     png_set_eXIf_1(png_ptr, info_ptr, num_exif, exif);
 
-    exif           - Exif profile (array of
-                     png_byte) (PNG_INFO_eXIf)
+    exif           - Exif profile (array of png_byte)
+                     (PNG_INFO_eXIf)
 
     png_set_hIST(png_ptr, info_ptr, hist);
 
@@ -3646,12 +3637,12 @@
     png_set_tIME(png_ptr, info_ptr, mod_time);
 
     mod_time       - time image was last modified
-                     (PNG_VALID_tIME)
+                     (PNG_INFO_tIME)
 
     png_set_bKGD(png_ptr, info_ptr, background);
 
     background     - background color (of type
-                     png_color_16p) (PNG_VALID_bKGD)
+                     png_color_16p) (PNG_INFO_bKGD)
 
     png_set_text(png_ptr, info_ptr, text_ptr, num_text);
 
@@ -4737,7 +4728,7 @@
 own functions as described above.  These functions also provide a void
 pointer that can be retrieved via
 
-    mem_ptr=png_get_mem_ptr(png_ptr);
+    mem_ptr = png_get_mem_ptr(png_ptr);
 
 Your replacement memory functions must have prototypes as follows:
 
@@ -5034,7 +5025,7 @@
 can still use PNG_DEBUG to control your own debugging:
 
    #ifdef PNG_DEBUG
-       fprintf(stderr, ...
+       fprintf(stderr, ...);
    #endif
 
 When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
@@ -5211,7 +5202,7 @@
 The function
     png_check_sig(sig, num)
 was replaced with
-    !png_sig_cmp(sig, 0, num)
+    png_sig_cmp(sig, 0, num) == 0
 It has been deprecated since libpng-0.90.
 
 The function
@@ -5275,8 +5266,8 @@
 png_set_asm_flags(), and png_mmx_supported()
 
 We removed the obsolete png_check_sig(), png_memcpy_check(), and
-png_memset_check() functions.  Instead use !png_sig_cmp(), memcpy(),
-and memset(), respectively.
+png_memset_check() functions.  Instead use png_sig_cmp() == 0,
+memcpy(), and memset(), respectively.
 
 The function png_set_gray_1_2_4_to_8() was removed. It has been
 deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with
@@ -5758,7 +5749,7 @@
 best choice for use in configure scripts for detecting the presence of any
 libpng version since 0.88.  In an autoconf "configure.in" you could use
 
-    AC_CHECK_LIB(png, png_get_io_ptr, ...
+    AC_CHECK_LIB(png, png_get_io_ptr, ...)
 
 .SH XV. Source code repository
 
@@ -5767,12 +5758,12 @@
 going back to version 0.70.  You can access the git repository (read only)
 at
 
-    https://github.com/glennrp/libpng or
+    https://github.com/pnggroup/libpng or
     https://git.code.sf.net/p/libpng/code.git
 
 or you can browse it with a web browser at
 
-    https://github.com/glennrp/libpng or
+    https://github.com/pnggroup/libpng or
     https://sourceforge.net/p/libpng/code/ci/libpng16/tree/
 
 Patches can be sent to png-mng-implement at lists.sourceforge.net or
@@ -5782,7 +5773,7 @@
 
 or as a "pull request" to
 
-    https://github.com/glennrp/libpng/pulls
+    https://github.com/pnggroup/libpng/pulls
 
 We also accept patches built from the tar or zip distributions, and
 simple verbal descriptions of bug fixes, reported either to the
@@ -5995,35 +5986,25 @@
 public release number plus "betaNN" or "rcNN".
 
 .SH "SEE ALSO"
-.IR libpngpf(3) ", " png(5)
-.LP
-.IR libpng :
+.BR "png"(5)
 .IP
-https://libpng.sourceforge.io/ (follow the [DOWNLOAD] link)
-http://www.libpng.org/pub/png
-
+The PNG (Portable Network Graphics) format specification.
 .LP
-.IR zlib :
+.B libpng
 .IP
-(generally) at the same location as
-.I libpng
-or at
+http://www.libpng.org/pub/png/libpng.html (canonical home page)
 .br
-https://zlib.net/
-
+https://github.com/pnggroup/libpng (canonical Git repository)
+.br
+https://libpng.sourceforge.io (downloadable archives)
 .LP
-.IR PNG specification: RFC 2083
+.B zlib
 .IP
-(generally) at the same location as
-.I libpng
-or at
+https://zlib.net (canonical home page)
 .br
-https://www.ietf.org/rfc/rfc2083.txt
+https://github.com/madler/zlib (canonical Git repository)
 .br
-or (as a W3C Recommendation) at
-.br
-https://www.w3.org/TR/REC-png.html
-
+A copy of zlib may also be found at the same location as libpng.
 .LP
 In the case of any inconsistency between the PNG specification
 and this library, the specification takes precedence.
@@ -6043,10 +6024,10 @@
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Maintained by Cosmin Truta.
 
-Supported by the PNG development group
+Supported by the PNG development group.
 .br
-png-mng-implement at lists.sourceforge.net (subscription required; visit
-https://lists.sourceforge.net/lists/listinfo/png-mng-implement
-to subscribe).
+png-mng-implement at lists.sourceforge.net. (Subscription is required;
+visit https://lists.sourceforge.net/lists/listinfo/png-mng-implement
+to subscribe.)
 
 .\" end of man page
diff --git a/libpng.pc.in b/libpng.pc.in
index 9708e9a..de127d4 100644
--- a/libpng.pc.in
+++ b/libpng.pc.in
@@ -6,7 +6,7 @@
 Name: libpng
 Description: Loads and saves PNG files
 Version: @PNGLIB_VERSION@
-Requires: zlib
+Requires.private: zlib
 Libs: -L${libdir} -lpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 Libs.private: @LIBS@
 Cflags: -I${includedir}
diff --git a/libpngpf.3 b/libpngpf.3
index 6909c70..a469205 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "April 14, 2019"
+.TH LIBPNGPF 3 "January 29, 2024"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.37
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.42
 (private functions)
 
 .SH SYNOPSIS
diff --git a/loongarch/.editorconfig b/loongarch/.editorconfig
new file mode 100644
index 0000000..b142d82
--- /dev/null
+++ b/loongarch/.editorconfig
@@ -0,0 +1,7 @@
+# https://editorconfig.org
+
+root = false
+
+# FIXME
+[*.[ch]]
+max_line_length = unset
diff --git a/loongarch/filter_lsx_intrinsics.c b/loongarch/filter_lsx_intrinsics.c
new file mode 100644
index 0000000..af6cc76
--- /dev/null
+++ b/loongarch/filter_lsx_intrinsics.c
@@ -0,0 +1,412 @@
+/* filter_lsx_intrinsics.c - LSX optimized filter functions
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ * All rights reserved.
+ * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2016 Glenn Randers-Pehrson
+ * Contributed by Jin Bo (jinbo@loongson.cn)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "../pngpriv.h"
+
+#ifdef PNG_READ_SUPPORTED
+
+#if PNG_LOONGARCH_LSX_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
+
+#include <lsxintrin.h>
+
+#define LSX_LD(psrc) __lsx_vld((psrc), 0)
+
+#define LSX_LD_2(psrc, stride, out0, out1) \
+{                                          \
+   out0 = LSX_LD(psrc);                    \
+   out1 = LSX_LD(psrc + stride);           \
+}
+
+#define LSX_LD_4(psrc, stride, out0, out1, out2, out3) \
+{                                                      \
+   LSX_LD_2(psrc, stride, out0, out1);                 \
+   LSX_LD_2(psrc + stride * 2, stride, out2, out3);    \
+}
+
+#define LSX_ST(in, pdst) __lsx_vst(in, (pdst), 0)
+
+#define LSX_ST_2(in0, in1, pdst, stride) \
+{                                        \
+   LSX_ST(in0, pdst);                    \
+   LSX_ST(in1, pdst + stride);           \
+}
+
+#define LSX_ST_4(in0, in1, in2, in3, pdst, stride) \
+{                                                  \
+   LSX_ST_2(in0, in1, pdst, stride);               \
+   LSX_ST_2(in2, in3, pdst + stride * 2, stride);  \
+}
+
+#define LSX_ADD_B(in0, in1, out0) \
+{                                 \
+   out0 = __lsx_vadd_b(in0, in1); \
+}
+
+#define LSX_ADD_B_2(in0, in1, in2, in3, out0, out1) \
+{                                                   \
+   LSX_ADD_B(in0, in1, out0);                       \
+   LSX_ADD_B(in2, in3, out1);                       \
+}
+
+#define LSX_ADD_B_4(in0, in1, in2, in3, in4, in5,     \
+                    in6, in7, out0, out1, out2, out3) \
+{                                                     \
+   LSX_ADD_B_2(in0, in1, in2, in3, out0, out1);       \
+   LSX_ADD_B_2(in4, in5, in6, in7, out2, out3);       \
+}
+
+#define LSX_ABS_B_3(in0, in1, in2, out0, out1, out2) \
+{                                                    \
+   out0 = __lsx_vadda_h(in0, zero);                  \
+   out1 = __lsx_vadda_h(in1, zero);                  \
+   out2 = __lsx_vadda_h(in2, zero);                  \
+}
+
+#define LSX_ILVL_B(in_h, in_l, out0)  \
+{                                     \
+   out0 = __lsx_vilvl_b(in_h, in_l);  \
+}
+
+#define LSX_ILVL_B_2(in0_h, in0_l, in1_h, in1_l, out0, out1) \
+{                                                            \
+   LSX_ILVL_B(in0_h, in0_l, out0);                           \
+   LSX_ILVL_B(in1_h, in1_l, out1);                           \
+}
+
+#define LSX_HSUB_HU_BU_2(in0, in1, out0, out1) \
+{                                              \
+   out0 = __lsx_vhsubw_hu_bu(in0, in0);        \
+   out1 = __lsx_vhsubw_hu_bu(in1, in1);        \
+}
+
+#define LSX_CMP_PICK_SMALLER(in0, in1, in2, in3, in4, in5, out0) \
+{                                                                \
+   __m128i _cmph, _cmpb, _in0, _in3;                             \
+   _cmph = __lsx_vslt_h(in1, in0);                               \
+   _cmpb = __lsx_vpickev_b(_cmph, _cmph);                        \
+   _in0  = __lsx_vmin_bu(in0,in1);                               \
+   _in3  = __lsx_vbitsel_v(in3, in4, _cmpb);                     \
+   _cmph = __lsx_vslt_h(in2, _in0);                              \
+   _cmpb = __lsx_vpickev_b(_cmph, _cmph);                        \
+   _in3  = __lsx_vbitsel_v(_in3, in5, _cmpb);                    \
+   out0  = __lsx_vadd_b(out0, _in3);                             \
+}
+
+void png_read_filter_row_up_lsx(png_row_infop row_info, png_bytep row,
+                                png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   png_bytep rp = row;
+   png_const_bytep pp = prev_row;
+   __m128i vec_0, vec_1, vec_2, vec_3;
+   __m128i vec_4, vec_5, vec_6, vec_7;
+
+   while (n >= 64)
+   {
+      LSX_LD_4(rp, 16, vec_0, vec_1, vec_2, vec_3);
+      LSX_LD_4(pp, 16, vec_4, vec_5, vec_6, vec_7);
+      pp += 64;
+      LSX_ADD_B_4(vec_0 ,vec_4, vec_1, vec_5, vec_2, vec_6,
+                  vec_3, vec_7, vec_0, vec_1, vec_2, vec_3);
+      LSX_ST_4(vec_0, vec_1, vec_2, vec_3, rp, 16);
+      rp += 64;
+      n -= 64;
+   }
+   if (n & 63)
+   {
+      if (n >= 32)
+      {
+         LSX_LD_2(rp, 16, vec_0, vec_1);
+         LSX_LD_2(pp, 16, vec_2, vec_3);
+         pp += 32;
+         LSX_ADD_B_2(vec_0, vec_2, vec_1, vec_3, vec_0, vec_1);
+         LSX_ST_2(vec_0, vec_1, rp, 16);
+         rp += 32;
+         n -= 32;
+      }
+      if (n & 31)
+      {
+         if (n >= 16)
+         {
+            vec_0 = LSX_LD(rp);
+            vec_1 = LSX_LD(pp);
+            pp += 16;
+            LSX_ADD_B(vec_0, vec_1, vec_0);
+            LSX_ST(vec_0, rp);
+            rp += 16;
+            n -= 16;
+         }
+         if (n >= 8)
+         {
+            vec_0 = __lsx_vldrepl_d(rp, 0);
+            vec_1 = __lsx_vldrepl_d(pp, 0);
+            vec_0 = __lsx_vadd_b(vec_0, vec_1);
+            __lsx_vstelm_d(vec_0, rp, 0, 0);
+            rp += 8;
+            pp += 8;
+            n -= 8;
+         }
+         while (n--)
+         {
+            *rp = *rp + *pp++;
+            rp++;
+         }
+      }
+   }
+}
+
+void png_read_filter_row_sub3_lsx(png_row_infop row_info, png_bytep row,
+                                  png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   png_uint_32 tmp;
+   png_bytep nxt = row;
+   __m128i vec_0, vec_1;
+
+   PNG_UNUSED(prev_row);
+
+   vec_0 = __lsx_vldrepl_w(nxt, 0);
+   nxt += 3;
+   n -= 3;
+
+   while (n >= 3)
+   {
+      vec_1 = __lsx_vldrepl_w(nxt, 0);
+      vec_1 = __lsx_vadd_b(vec_1, vec_0);
+      __lsx_vstelm_h(vec_1, nxt, 0, 0);
+      vec_0 = vec_1;
+      nxt += 2;
+      __lsx_vstelm_b(vec_1, nxt, 0, 2);
+      nxt += 1;
+      n -= 3;
+   }
+
+   row = nxt - 3;
+   while (n--)
+   {
+      *nxt = *nxt + *row++;
+      nxt++;
+   }
+}
+
+void png_read_filter_row_sub4_lsx(png_row_infop row_info, png_bytep row,
+                                  png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   __m128i vec_0, vec_1;
+
+   PNG_UNUSED(prev_row);
+
+   vec_0 = __lsx_vldrepl_w(row, 0);
+   row += 4;
+   n -= 4;
+
+   while (n >= 4)
+   {
+      vec_1 = __lsx_vldrepl_w(row, 0);
+      vec_1 = __lsx_vadd_b(vec_1, vec_0);
+      __lsx_vstelm_w(vec_1, row, 0, 0);
+      vec_0 = vec_1;
+      row += 4;
+      n -= 4;
+   }
+}
+
+void png_read_filter_row_avg3_lsx(png_row_infop row_info, png_bytep row,
+                                  png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   png_bytep nxt = row;
+   png_const_bytep prev_nxt = prev_row;
+   __m128i vec_0, vec_1, vec_2;
+
+   vec_0 = __lsx_vldrepl_w(nxt, 0);
+   vec_1 = __lsx_vldrepl_w(prev_nxt, 0);
+   prev_nxt += 3;
+   vec_1 = __lsx_vsrli_b(vec_1, 1);
+   vec_1 = __lsx_vadd_b(vec_1, vec_0);
+   __lsx_vstelm_h(vec_1, nxt, 0, 0);
+   nxt += 2;
+   __lsx_vstelm_b(vec_1, nxt, 0, 2);
+   nxt += 1;
+   n -= 3;
+
+   while (n >= 3)
+   {
+      vec_2 = vec_1;
+      vec_0 = __lsx_vldrepl_w(nxt, 0);
+      vec_1 = __lsx_vldrepl_w(prev_nxt, 0);
+      prev_nxt += 3;
+
+      vec_1 = __lsx_vavg_bu(vec_1, vec_2);
+      vec_1 = __lsx_vadd_b(vec_1, vec_0);
+
+      __lsx_vstelm_h(vec_1, nxt, 0, 0);
+      nxt += 2;
+      __lsx_vstelm_b(vec_1, nxt, 0, 2);
+      nxt += 1;
+      n -= 3;
+   }
+
+   row = nxt - 3;
+   while (n--)
+   {
+      vec_2 = __lsx_vldrepl_b(row, 0);
+      row++;
+      vec_0 = __lsx_vldrepl_b(nxt, 0);
+      vec_1 = __lsx_vldrepl_b(prev_nxt, 0);
+      prev_nxt++;
+
+      vec_1 = __lsx_vavg_bu(vec_1, vec_2);
+      vec_1 = __lsx_vadd_b(vec_1, vec_0);
+
+      __lsx_vstelm_b(vec_1, nxt, 0, 0);
+      nxt++;
+   }
+}
+
+void png_read_filter_row_avg4_lsx(png_row_infop row_info, png_bytep row,
+                                  png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   __m128i vec_0, vec_1, vec_2;
+
+   vec_0 = __lsx_vldrepl_w(row, 0);
+   vec_1 = __lsx_vldrepl_w(prev_row, 0);
+   prev_row += 4;
+   vec_1 = __lsx_vsrli_b(vec_1, 1);
+   vec_1 = __lsx_vadd_b(vec_1, vec_0);
+   __lsx_vstelm_w(vec_1, row, 0, 0);
+   row += 4;
+   n -= 4;
+
+   while (n >= 4)
+   {
+      vec_2 = vec_1;
+      vec_0 = __lsx_vldrepl_w(row, 0);
+      vec_1 = __lsx_vldrepl_w(prev_row, 0);
+      prev_row += 4;
+
+      vec_1 = __lsx_vavg_bu(vec_1, vec_2);
+      vec_1 = __lsx_vadd_b(vec_1, vec_0);
+
+      __lsx_vstelm_w(vec_1, row, 0, 0);
+      row += 4;
+      n -= 4;
+   }
+}
+
+void png_read_filter_row_paeth3_lsx(png_row_infop row_info,
+                                    png_bytep row,
+                                    png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   png_bytep nxt = row;
+   png_const_bytep prev_nxt = prev_row;
+   __m128i vec_a, vec_b, vec_c, vec_d;
+   __m128i vec_pa, vec_pb, vec_pc;
+   __m128i zero = {0};
+
+   vec_a = __lsx_vldrepl_w(nxt, 0);
+   vec_b = __lsx_vldrepl_w(prev_nxt, 0);
+   prev_nxt += 3;
+   vec_d = __lsx_vadd_b(vec_a, vec_b);
+   __lsx_vstelm_h(vec_d, nxt, 0, 0);
+   nxt += 2;
+   __lsx_vstelm_b(vec_d, nxt, 0, 2);
+   nxt += 1;
+   n -= 3;
+
+   while (n >= 3)
+   {
+      vec_a = vec_d;
+      vec_c = vec_b;
+      vec_b = __lsx_vldrepl_w(prev_nxt, 0);
+      prev_nxt += 3;
+      vec_d = __lsx_vldrepl_w(nxt, 0);
+
+      LSX_ILVL_B_2(vec_b, vec_c, vec_a, vec_c, vec_pa, vec_pb);
+      LSX_HSUB_HU_BU_2(vec_pa, vec_pb, vec_pa, vec_pb);
+      vec_pc = __lsx_vadd_h(vec_pa, vec_pb);
+      LSX_ABS_B_3(vec_pa, vec_pb, vec_pc, vec_pa, vec_pb, vec_pc);
+      LSX_CMP_PICK_SMALLER(vec_pa, vec_pb, vec_pc, vec_a, vec_b, vec_c, vec_d);
+
+      __lsx_vstelm_h(vec_d, nxt, 0, 0);
+      nxt += 2;
+      __lsx_vstelm_b(vec_d, nxt, 0, 2);
+      nxt += 1;
+      n -= 3;
+   }
+
+   prev_row = prev_nxt - 3;
+   row = nxt - 3;
+   while (n--)
+   {
+      vec_a = __lsx_vldrepl_b(row, 0);
+      row++;
+      vec_b = __lsx_vldrepl_b(prev_nxt, 0);
+      prev_nxt++;
+      vec_c = __lsx_vldrepl_b(prev_row, 0);
+      prev_row++;
+      vec_d = __lsx_vldrepl_b(nxt, 0);
+
+      LSX_ILVL_B_2(vec_b, vec_c, vec_a, vec_c, vec_pa, vec_pb);
+      LSX_HSUB_HU_BU_2(vec_pa, vec_pb, vec_pa, vec_pb);
+      vec_pc = __lsx_vadd_h(vec_pa, vec_pb);
+      LSX_ABS_B_3(vec_pa, vec_pb, vec_pc, vec_pa, vec_pb, vec_pc);
+      LSX_CMP_PICK_SMALLER(vec_pa, vec_pb, vec_pc, vec_a, vec_b, vec_c, vec_d);
+
+      __lsx_vstelm_b(vec_d, nxt, 0, 0);
+      nxt++;
+   }
+}
+
+void png_read_filter_row_paeth4_lsx(png_row_infop row_info,
+                                    png_bytep row,
+                                    png_const_bytep prev_row)
+{
+   size_t n = row_info->rowbytes;
+   __m128i vec_a, vec_b, vec_c, vec_d;
+   __m128i vec_pa, vec_pb, vec_pc;
+   __m128i zero = {0};
+
+   vec_a = __lsx_vldrepl_w(row, 0);
+   vec_b = __lsx_vldrepl_w(prev_row, 0);
+   prev_row += 4;
+   vec_d = __lsx_vadd_b(vec_a, vec_b);
+   __lsx_vstelm_w(vec_d, row, 0, 0);
+   row += 4;
+   n -= 4;
+
+   while (n >= 4)
+   {
+      vec_a = vec_d;
+      vec_c = vec_b;
+      vec_b = __lsx_vldrepl_w(prev_row, 0);
+      prev_row += 4;
+      vec_d = __lsx_vldrepl_w(row, 0);
+
+      LSX_ILVL_B_2(vec_b, vec_c, vec_a, vec_c, vec_pa, vec_pb);
+      LSX_HSUB_HU_BU_2(vec_pa, vec_pb, vec_pa, vec_pb);
+      vec_pc = __lsx_vadd_h(vec_pa, vec_pb);
+      LSX_ABS_B_3(vec_pa, vec_pb, vec_pc, vec_pa, vec_pb, vec_pc);
+      LSX_CMP_PICK_SMALLER(vec_pa, vec_pb, vec_pc, vec_a, vec_b, vec_c, vec_d);
+
+      __lsx_vstelm_w(vec_d, row, 0, 0);
+      row += 4;
+      n -= 4;
+   }
+}
+
+#endif /* PNG_LOONGARCH_LSX_IMPLEMENTATION == 1 (intrinsics) */
+#endif /* PNG_READ_SUPPORTED */
diff --git a/loongarch/loongarch_lsx_init.c b/loongarch/loongarch_lsx_init.c
new file mode 100644
index 0000000..2c80fe8
--- /dev/null
+++ b/loongarch/loongarch_lsx_init.c
@@ -0,0 +1,65 @@
+/* loongarch_lsx_init.c - LSX optimized filter functions
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ * All rights reserved.
+ * Contributed by Jin Bo <jinbo@loongson.cn>
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "../pngpriv.h"
+
+#ifdef PNG_READ_SUPPORTED
+#if PNG_LOONGARCH_LSX_IMPLEMENTATION == 1
+
+#include <sys/auxv.h>
+
+#define LA_HWCAP_LSX    (1<<4)
+static int png_has_lsx(void)
+{
+    int flags = 0;
+    int flag  = (int)getauxval(AT_HWCAP);
+
+    if (flag & LA_HWCAP_LSX)
+        return 1;
+
+    return 0;
+}
+
+void
+png_init_filter_functions_lsx(png_structp pp, unsigned int bpp)
+{
+   /* IMPORTANT: any new external functions used here must be declared using
+    * PNG_INTERNAL_FUNCTION in ../pngpriv.h.  This is required so that the
+    * 'prefix' option to configure works:
+    *
+    *    ./configure --with-libpng-prefix=foobar_
+    *
+    * Verify you have got this right by running the above command, doing a build
+    * and examining pngprefix.h; it must contain a #define for every external
+    * function you add.  (Notice that this happens automatically for the
+    * initialization function.)
+    */
+
+   if (png_has_lsx())
+   {
+      pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_lsx;
+      if (bpp == 3)
+      {
+         pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth3_lsx;
+      }
+      else if (bpp == 4)
+      {
+         pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_lsx;
+         pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_lsx;
+      }
+   }
+}
+
+#endif /* PNG_LOONGARCH_LSX_IMPLEMENTATION == 1 */
+#endif /* PNG_READ_SUPPORTED */
diff --git a/ltmain.sh b/ltmain.sh
index 0f0a2da..2a50d7f 100755
--- a/ltmain.sh
+++ b/ltmain.sh
@@ -1,12 +1,12 @@
-#! /bin/sh
+#! /usr/bin/env sh
 ## DO NOT EDIT - This file generated from ./build-aux/ltmain.in
-##               by inline-source v2014-01-03.01
+##               by inline-source v2019-02-19.15
 
-# libtool (GNU libtool) 2.4.6
+# libtool (GNU libtool) 2.4.7
 # Provide generalized library-building support services.
 # Written by Gordon Matzigkeit <gord@gnu.ai.mit.edu>, 1996
 
-# Copyright (C) 1996-2015 Free Software Foundation, Inc.
+# Copyright (C) 1996-2019, 2021-2022 Free Software Foundation, Inc.
 # This is free software; see the source for copying conditions.  There is NO
 # warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
@@ -31,8 +31,8 @@
 
 PROGRAM=libtool
 PACKAGE=libtool
-VERSION=2.4.6
-package_revision=2.4.6
+VERSION=2.4.7
+package_revision=2.4.7
 
 
 ## ------ ##
@@ -64,34 +64,25 @@
 # libraries, which are installed to $pkgauxdir.
 
 # Set a version string for this script.
-scriptversion=2015-01-20.17; # UTC
+scriptversion=2019-02-19.15; # UTC
 
 # General shell script boiler plate, and helper functions.
 # Written by Gary V. Vaughan, 2004
 
-# Copyright (C) 2004-2015 Free Software Foundation, Inc.
-# This is free software; see the source for copying conditions.  There is NO
-# warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# This is free software.  There is NO warranty; not even for
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Copyright (C) 2004-2019, 2021 Bootstrap Authors
+#
+# This file is dual licensed under the terms of the MIT license
+# <https://opensource.org/license/MIT>, and GPL version 2 or later
+# <http://www.gnu.org/licenses/gpl-2.0.html>.  You must apply one of
+# these licenses when using or redistributing this software or any of
+# the files within it.  See the URLs above, or the file `LICENSE`
+# included in the Bootstrap distribution for the full license texts.
 
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3 of the License, or
-# (at your option) any later version.
-
-# As a special exception to the GNU General Public License, if you distribute
-# this file as part of a program or library that is built using GNU Libtool,
-# you may include this file under the same distribution terms that you use
-# for the rest of that program.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNES FOR A PARTICULAR PURPOSE. See the GNU
-# General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program. If not, see <http://www.gnu.org/licenses/>.
-
-# Please report bugs or propose patches to gary@gnu.org.
+# Please report bugs or propose patches to:
+# <https://github.com/gnulib-modules/bootstrap/issues>
 
 
 ## ------ ##
@@ -139,9 +130,12 @@
 	  _G_safe_locale=\"$_G_var=C; \$_G_safe_locale\"
 	fi"
 done
-
-# CDPATH.
-(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
+# These NLS vars are set unconditionally (bootstrap issue #24).  Unset those
+# in case the environment reset is needed later and the $save_* variant is not
+# defined (see the code above).
+LC_ALL=C
+LANGUAGE=C
+export LANGUAGE LC_ALL
 
 # Make sure IFS has a sensible default
 sp=' '
@@ -159,6 +153,26 @@
 fi
 
 
+# func_unset VAR
+# --------------
+# Portably unset VAR.
+# In some shells, an 'unset VAR' statement leaves a non-zero return
+# status if VAR is already unset, which might be problematic if the
+# statement is used at the end of a function (thus poisoning its return
+# value) or when 'set -e' is active (causing even a spurious abort of
+# the script in this case).
+func_unset ()
+{
+    { eval $1=; (eval unset $1) >/dev/null 2>&1 && eval unset $1 || : ; }
+}
+
+
+# Make sure CDPATH doesn't cause `cd` commands to output the target dir.
+func_unset CDPATH
+
+# Make sure ${,E,F}GREP behave sanely.
+func_unset GREP_OPTIONS
+
 
 ## ------------------------- ##
 ## Locate command utilities. ##
@@ -259,7 +273,7 @@
     rm -f conftest.in conftest.tmp conftest.nl conftest.out
   }
 
-  func_path_progs "sed gsed" func_check_prog_sed $PATH:/usr/xpg4/bin
+  func_path_progs "sed gsed" func_check_prog_sed "$PATH:/usr/xpg4/bin"
   rm -f conftest.sed
   SED=$func_path_progs_result
 }
@@ -295,7 +309,7 @@
     rm -f conftest.in conftest.tmp conftest.nl conftest.out
   }
 
-  func_path_progs "grep ggrep" func_check_prog_grep $PATH:/usr/xpg4/bin
+  func_path_progs "grep ggrep" func_check_prog_grep "$PATH:/usr/xpg4/bin"
   GREP=$func_path_progs_result
 }
 
@@ -360,6 +374,35 @@
   s/\\([^$_G_bs]\\)$_G_bs2$_G_dollar/\\1$_G_bs2$_G_bs$_G_dollar/g
   s/\n//g"
 
+# require_check_ifs_backslash
+# ---------------------------
+# Check if we can use backslash as IFS='\' separator, and set
+# $check_ifs_backshlash_broken to ':' or 'false'.
+require_check_ifs_backslash=func_require_check_ifs_backslash
+func_require_check_ifs_backslash ()
+{
+  _G_save_IFS=$IFS
+  IFS='\'
+  _G_check_ifs_backshlash='a\\b'
+  for _G_i in $_G_check_ifs_backshlash
+  do
+  case $_G_i in
+  a)
+    check_ifs_backshlash_broken=false
+    ;;
+  '')
+    break
+    ;;
+  *)
+    check_ifs_backshlash_broken=:
+    break
+    ;;
+  esac
+  done
+  IFS=$_G_save_IFS
+  require_check_ifs_backslash=:
+}
+
 
 ## ----------------- ##
 ## Global variables. ##
@@ -580,16 +623,16 @@
   {
     $debug_cmd
 
-    func_quote_for_eval "$2"
-    eval "$1+=\\ \$func_quote_for_eval_result"
+    func_quote_arg pretty "$2"
+    eval "$1+=\\ \$func_quote_arg_result"
   }'
 else
   func_append_quoted ()
   {
     $debug_cmd
 
-    func_quote_for_eval "$2"
-    eval "$1=\$$1\\ \$func_quote_for_eval_result"
+    func_quote_arg pretty "$2"
+    eval "$1=\$$1\\ \$func_quote_arg_result"
   }
 fi
 
@@ -1091,85 +1134,203 @@
 }
 
 
-# func_quote_for_eval ARG...
-# --------------------------
-# Aesthetically quote ARGs to be evaled later.
-# This function returns two values:
-#   i) func_quote_for_eval_result
-#      double-quoted, suitable for a subsequent eval
-#  ii) func_quote_for_eval_unquoted_result
-#      has all characters that are still active within double
-#      quotes backslashified.
-func_quote_for_eval ()
+# func_quote_portable EVAL ARG
+# ----------------------------
+# Internal function to portably implement func_quote_arg.  Note that we still
+# keep attention to performance here so we as much as possible try to avoid
+# calling sed binary (so far O(N) complexity as long as func_append is O(1)).
+func_quote_portable ()
 {
     $debug_cmd
 
-    func_quote_for_eval_unquoted_result=
-    func_quote_for_eval_result=
-    while test 0 -lt $#; do
-      case $1 in
+    $require_check_ifs_backslash
+
+    func_quote_portable_result=$2
+
+    # one-time-loop (easy break)
+    while true
+    do
+      if $1; then
+        func_quote_portable_result=`$ECHO "$2" | $SED \
+          -e "$sed_double_quote_subst" -e "$sed_double_backslash"`
+        break
+      fi
+
+      # Quote for eval.
+      case $func_quote_portable_result in
         *[\\\`\"\$]*)
-	  _G_unquoted_arg=`printf '%s\n' "$1" |$SED "$sed_quote_subst"` ;;
-        *)
-          _G_unquoted_arg=$1 ;;
-      esac
-      if test -n "$func_quote_for_eval_unquoted_result"; then
-	func_append func_quote_for_eval_unquoted_result " $_G_unquoted_arg"
-      else
-        func_append func_quote_for_eval_unquoted_result "$_G_unquoted_arg"
-      fi
+          # Fallback to sed for $func_check_bs_ifs_broken=:, or when the string
+          # contains the shell wildcard characters.
+          case $check_ifs_backshlash_broken$func_quote_portable_result in
+            :*|*[\[\*\?]*)
+              func_quote_portable_result=`$ECHO "$func_quote_portable_result" \
+                  | $SED "$sed_quote_subst"`
+              break
+              ;;
+          esac
 
-      case $_G_unquoted_arg in
-        # Double-quote args containing shell metacharacters to delay
-        # word splitting, command substitution and variable expansion
-        # for a subsequent eval.
-        # Many Bourne shells cannot handle close brackets correctly
-        # in scan sets, so we specify it separately.
-        *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
-          _G_quoted_arg=\"$_G_unquoted_arg\"
+          func_quote_portable_old_IFS=$IFS
+          for _G_char in '\' '`' '"' '$'
+          do
+            # STATE($1) PREV($2) SEPARATOR($3)
+            set start "" ""
+            func_quote_portable_result=dummy"$_G_char$func_quote_portable_result$_G_char"dummy
+            IFS=$_G_char
+            for _G_part in $func_quote_portable_result
+            do
+              case $1 in
+              quote)
+                func_append func_quote_portable_result "$3$2"
+                set quote "$_G_part" "\\$_G_char"
+                ;;
+              start)
+                set first "" ""
+                func_quote_portable_result=
+                ;;
+              first)
+                set quote "$_G_part" ""
+                ;;
+              esac
+            done
+          done
+          IFS=$func_quote_portable_old_IFS
           ;;
-        *)
-          _G_quoted_arg=$_G_unquoted_arg
-	  ;;
+        *) ;;
       esac
-
-      if test -n "$func_quote_for_eval_result"; then
-	func_append func_quote_for_eval_result " $_G_quoted_arg"
-      else
-        func_append func_quote_for_eval_result "$_G_quoted_arg"
-      fi
-      shift
+      break
     done
+
+    func_quote_portable_unquoted_result=$func_quote_portable_result
+    case $func_quote_portable_result in
+      # double-quote args containing shell metacharacters to delay
+      # word splitting, command substitution and variable expansion
+      # for a subsequent eval.
+      # many bourne shells cannot handle close brackets correctly
+      # in scan sets, so we specify it separately.
+      *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
+        func_quote_portable_result=\"$func_quote_portable_result\"
+        ;;
+    esac
 }
 
 
-# func_quote_for_expand ARG
-# -------------------------
-# Aesthetically quote ARG to be evaled later; same as above,
-# but do not quote variable references.
-func_quote_for_expand ()
+# func_quotefast_eval ARG
+# -----------------------
+# Quote one ARG (internal).  This is equivalent to 'func_quote_arg eval ARG',
+# but optimized for speed.  Result is stored in $func_quotefast_eval.
+if test xyes = `(x=; printf -v x %q yes; echo x"$x") 2>/dev/null`; then
+  printf -v _GL_test_printf_tilde %q '~'
+  if test '\~' = "$_GL_test_printf_tilde"; then
+    func_quotefast_eval ()
+    {
+      printf -v func_quotefast_eval_result %q "$1"
+    }
+  else
+    # Broken older Bash implementations.  Make those faster too if possible.
+    func_quotefast_eval ()
+    {
+      case $1 in
+        '~'*)
+          func_quote_portable false "$1"
+          func_quotefast_eval_result=$func_quote_portable_result
+          ;;
+        *)
+          printf -v func_quotefast_eval_result %q "$1"
+          ;;
+      esac
+    }
+  fi
+else
+  func_quotefast_eval ()
+  {
+    func_quote_portable false "$1"
+    func_quotefast_eval_result=$func_quote_portable_result
+  }
+fi
+
+
+# func_quote_arg MODEs ARG
+# ------------------------
+# Quote one ARG to be evaled later.  MODEs argument may contain zero or more
+# specifiers listed below separated by ',' character.  This function returns two
+# values:
+#   i) func_quote_arg_result
+#      double-quoted (when needed), suitable for a subsequent eval
+#  ii) func_quote_arg_unquoted_result
+#      has all characters that are still active within double
+#      quotes backslashified.  Available only if 'unquoted' is specified.
+#
+# Available modes:
+# ----------------
+# 'eval' (default)
+#       - escape shell special characters
+# 'expand'
+#       - the same as 'eval';  but do not quote variable references
+# 'pretty'
+#       - request aesthetic output, i.e. '"a b"' instead of 'a\ b'.  This might
+#         be used later in func_quote to get output like: 'echo "a b"' instead
+#         of 'echo a\ b'.  This is slower than default on some shells.
+# 'unquoted'
+#       - produce also $func_quote_arg_unquoted_result which does not contain
+#         wrapping double-quotes.
+#
+# Examples for 'func_quote_arg pretty,unquoted string':
+#
+#   string      | *_result              | *_unquoted_result
+#   ------------+-----------------------+-------------------
+#   "           | \"                    | \"
+#   a b         | "a b"                 | a b
+#   "a b"       | "\"a b\""             | \"a b\"
+#   *           | "*"                   | *
+#   z="${x-$y}" | "z=\"\${x-\$y}\""     | z=\"\${x-\$y}\"
+#
+# Examples for 'func_quote_arg pretty,unquoted,expand string':
+#
+#   string        |   *_result          |  *_unquoted_result
+#   --------------+---------------------+--------------------
+#   z="${x-$y}"   | "z=\"${x-$y}\""     | z=\"${x-$y}\"
+func_quote_arg ()
 {
-    $debug_cmd
-
-    case $1 in
-      *[\\\`\"]*)
-	_G_arg=`$ECHO "$1" | $SED \
-	    -e "$sed_double_quote_subst" -e "$sed_double_backslash"` ;;
-      *)
-        _G_arg=$1 ;;
-    esac
-
-    case $_G_arg in
-      # Double-quote args containing shell metacharacters to delay
-      # word splitting and command substitution for a subsequent eval.
-      # Many Bourne shells cannot handle close brackets correctly
-      # in scan sets, so we specify it separately.
-      *[\[\~\#\^\&\*\(\)\{\}\|\;\<\>\?\'\ \	]*|*]*|"")
-        _G_arg=\"$_G_arg\"
+    _G_quote_expand=false
+    case ,$1, in
+      *,expand,*)
+        _G_quote_expand=:
         ;;
     esac
 
-    func_quote_for_expand_result=$_G_arg
+    case ,$1, in
+      *,pretty,*|*,expand,*|*,unquoted,*)
+        func_quote_portable $_G_quote_expand "$2"
+        func_quote_arg_result=$func_quote_portable_result
+        func_quote_arg_unquoted_result=$func_quote_portable_unquoted_result
+        ;;
+      *)
+        # Faster quote-for-eval for some shells.
+        func_quotefast_eval "$2"
+        func_quote_arg_result=$func_quotefast_eval_result
+        ;;
+    esac
+}
+
+
+# func_quote MODEs ARGs...
+# ------------------------
+# Quote all ARGs to be evaled later and join them into single command.  See
+# func_quote_arg's description for more info.
+func_quote ()
+{
+    $debug_cmd
+    _G_func_quote_mode=$1 ; shift
+    func_quote_result=
+    while test 0 -lt $#; do
+      func_quote_arg "$_G_func_quote_mode" "$1"
+      if test -n "$func_quote_result"; then
+        func_append func_quote_result " $func_quote_arg_result"
+      else
+        func_append func_quote_result "$func_quote_arg_result"
+      fi
+      shift
+    done
 }
 
 
@@ -1215,8 +1376,8 @@
     _G_cmd=$1
     _G_fail_exp=${2-':'}
 
-    func_quote_for_expand "$_G_cmd"
-    eval "func_notquiet $func_quote_for_expand_result"
+    func_quote_arg pretty,expand "$_G_cmd"
+    eval "func_notquiet $func_quote_arg_result"
 
     $opt_dry_run || {
       eval "$_G_cmd"
@@ -1241,8 +1402,8 @@
     _G_fail_exp=${2-':'}
 
     $opt_quiet || {
-      func_quote_for_expand "$_G_cmd"
-      eval "func_echo $func_quote_for_expand_result"
+      func_quote_arg expand,pretty "$_G_cmd"
+      eval "func_echo $func_quote_arg_result"
     }
 
     $opt_dry_run || {
@@ -1369,30 +1530,26 @@
 # End:
 #! /bin/sh
 
-# Set a version string for this script.
-scriptversion=2014-01-07.03; # UTC
-
 # A portable, pluggable option parser for Bourne shell.
 # Written by Gary V. Vaughan, 2010
 
-# Copyright (C) 2010-2015 Free Software Foundation, Inc.
-# This is free software; see the source for copying conditions.  There is NO
-# warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# This is free software.  There is NO warranty; not even for
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Copyright (C) 2010-2019, 2021 Bootstrap Authors
+#
+# This file is dual licensed under the terms of the MIT license
+# <https://opensource.org/license/MIT>, and GPL version 2 or later
+# <http://www.gnu.org/licenses/gpl-2.0.html>.  You must apply one of
+# these licenses when using or redistributing this software or any of
+# the files within it.  See the URLs above, or the file `LICENSE`
+# included in the Bootstrap distribution for the full license texts.
 
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
+# Please report bugs or propose patches to:
+# <https://github.com/gnulib-modules/bootstrap/issues>
 
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-# Please report bugs or propose patches to gary@gnu.org.
+# Set a version string for this script.
+scriptversion=2019-02-19.15; # UTC
 
 
 ## ------ ##
@@ -1415,7 +1572,7 @@
 #
 # In order for the '--version' option to work, you will need to have a
 # suitably formatted comment like the one at the top of this file
-# starting with '# Written by ' and ending with '# warranty; '.
+# starting with '# Written by ' and ending with '# Copyright'.
 #
 # For '-h' and '--help' to work, you will also need a one line
 # description of your script's purpose in a comment directly above the
@@ -1427,7 +1584,7 @@
 # to display verbose messages only when your user has specified
 # '--verbose'.
 #
-# After sourcing this file, you can plug processing for additional
+# After sourcing this file, you can plug in processing for additional
 # options by amending the variables from the 'Configuration' section
 # below, and following the instructions in the 'Option parsing'
 # section further down.
@@ -1476,8 +1633,8 @@
 ## ------------------------- ##
 
 # This section contains functions for adding, removing, and running hooks
-# to the main code.  A hook is just a named list of of function, that can
-# be run in order later on.
+# in the main code.  A hook is just a list of function names that can be
+# run in order later on.
 
 # func_hookable FUNC_NAME
 # -----------------------
@@ -1510,7 +1667,8 @@
 
 # func_remove_hook FUNC_NAME HOOK_FUNC
 # ------------------------------------
-# Remove HOOK_FUNC from the list of functions called by FUNC_NAME.
+# Remove HOOK_FUNC from the list of hook functions to be called by
+# FUNC_NAME.
 func_remove_hook ()
 {
     $debug_cmd
@@ -1519,10 +1677,28 @@
 }
 
 
+# func_propagate_result FUNC_NAME_A FUNC_NAME_B
+# ---------------------------------------------
+# If the *_result variable of FUNC_NAME_A _is set_, assign its value to
+# *_result variable of FUNC_NAME_B.
+func_propagate_result ()
+{
+    $debug_cmd
+
+    func_propagate_result_result=:
+    if eval "test \"\${${1}_result+set}\" = set"
+    then
+      eval "${2}_result=\$${1}_result"
+    else
+      func_propagate_result_result=false
+    fi
+}
+
+
 # func_run_hooks FUNC_NAME [ARG]...
 # ---------------------------------
 # Run all hook functions registered to FUNC_NAME.
-# It is assumed that the list of hook functions contains nothing more
+# It's assumed that the list of hook functions contains nothing more
 # than a whitespace-delimited list of legal shell function names, and
 # no effort is wasted trying to catch shell meta-characters or preserve
 # whitespace.
@@ -1532,22 +1708,19 @@
 
     case " $hookable_fns " in
       *" $1 "*) ;;
-      *) func_fatal_error "'$1' does not support hook funcions.n" ;;
+      *) func_fatal_error "'$1' does not support hook functions." ;;
     esac
 
     eval _G_hook_fns=\$$1_hooks; shift
 
     for _G_hook in $_G_hook_fns; do
-      eval $_G_hook '"$@"'
-
-      # store returned options list back into positional
-      # parameters for next 'cmd' execution.
-      eval _G_hook_result=\$${_G_hook}_result
-      eval set dummy "$_G_hook_result"; shift
+      func_unset "${_G_hook}_result"
+      eval $_G_hook '${1+"$@"}'
+      func_propagate_result $_G_hook func_run_hooks
+      if $func_propagate_result_result; then
+        eval set dummy "$func_run_hooks_result"; shift
+      fi
     done
-
-    func_quote_for_eval ${1+"$@"}
-    func_run_hooks_result=$func_quote_for_eval_result
 }
 
 
@@ -1557,10 +1730,18 @@
 ## --------------- ##
 
 # In order to add your own option parsing hooks, you must accept the
-# full positional parameter list in your hook function, remove any
-# options that you action, and then pass back the remaining unprocessed
-# options in '<hooked_function_name>_result', escaped suitably for
-# 'eval'.  Like this:
+# full positional parameter list from your hook function.  You may remove
+# or edit any options that you action, and then pass back the remaining
+# unprocessed options in '<hooked_function_name>_result', escaped
+# suitably for 'eval'.
+#
+# The '<hooked_function_name>_result' variable is automatically unset
+# before your hook gets called; for best performance, only set the
+# *_result variable when necessary (i.e. don't call the 'func_quote'
+# function unnecessarily because it can be an expensive operation on some
+# machines).
+#
+# Like this:
 #
 #    my_options_prep ()
 #    {
@@ -1570,9 +1751,8 @@
 #        usage_message=$usage_message'
 #      -s, --silent       don'\''t print informational messages
 #    '
-#
-#        func_quote_for_eval ${1+"$@"}
-#        my_options_prep_result=$func_quote_for_eval_result
+#        # No change in '$@' (ignored completely by this hook).  Leave
+#        # my_options_prep_result variable intact.
 #    }
 #    func_add_hook func_options_prep my_options_prep
 #
@@ -1581,25 +1761,36 @@
 #    {
 #        $debug_cmd
 #
-#        # Note that for efficiency, we parse as many options as we can
+#        args_changed=false
+#
+#        # Note that, for efficiency, we parse as many options as we can
 #        # recognise in a loop before passing the remainder back to the
 #        # caller on the first unrecognised argument we encounter.
 #        while test $# -gt 0; do
 #          opt=$1; shift
 #          case $opt in
-#            --silent|-s) opt_silent=: ;;
+#            --silent|-s) opt_silent=:
+#                         args_changed=:
+#                         ;;
 #            # Separate non-argument short options:
 #            -s*)         func_split_short_opt "$_G_opt"
 #                         set dummy "$func_split_short_opt_name" \
 #                             "-$func_split_short_opt_arg" ${1+"$@"}
 #                         shift
+#                         args_changed=:
 #                         ;;
-#            *)            set dummy "$_G_opt" "$*"; shift; break ;;
+#            *)           # Make sure the first unrecognised option "$_G_opt"
+#                         # is added back to "$@" in case we need it later,
+#                         # if $args_changed was set to 'true'.
+#                         set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
 #          esac
 #        done
 #
-#        func_quote_for_eval ${1+"$@"}
-#        my_silent_option_result=$func_quote_for_eval_result
+#        # Only call 'func_quote' here if we processed at least one argument.
+#        if $args_changed; then
+#          func_quote eval ${1+"$@"}
+#          my_silent_option_result=$func_quote_result
+#        fi
 #    }
 #    func_add_hook func_parse_options my_silent_option
 #
@@ -1610,17 +1801,26 @@
 #
 #        $opt_silent && $opt_verbose && func_fatal_help "\
 #    '--silent' and '--verbose' options are mutually exclusive."
-#
-#        func_quote_for_eval ${1+"$@"}
-#        my_option_validation_result=$func_quote_for_eval_result
 #    }
 #    func_add_hook func_validate_options my_option_validation
 #
-# You'll alse need to manually amend $usage_message to reflect the extra
+# You'll also need to manually amend $usage_message to reflect the extra
 # options you parse.  It's preferable to append if you can, so that
 # multiple option parsing hooks can be added safely.
 
 
+# func_options_finish [ARG]...
+# ----------------------------
+# Finishing the option parse loop (call 'func_options' hooks ATM).
+func_options_finish ()
+{
+    $debug_cmd
+
+    func_run_hooks func_options ${1+"$@"}
+    func_propagate_result func_run_hooks func_options_finish
+}
+
+
 # func_options [ARG]...
 # ---------------------
 # All the functions called inside func_options are hookable. See the
@@ -1630,17 +1830,27 @@
 {
     $debug_cmd
 
-    func_options_prep ${1+"$@"}
-    eval func_parse_options \
-        ${func_options_prep_result+"$func_options_prep_result"}
-    eval func_validate_options \
-        ${func_parse_options_result+"$func_parse_options_result"}
+    _G_options_quoted=false
 
-    eval func_run_hooks func_options \
-        ${func_validate_options_result+"$func_validate_options_result"}
+    for my_func in options_prep parse_options validate_options options_finish
+    do
+      func_unset func_${my_func}_result
+      func_unset func_run_hooks_result
+      eval func_$my_func '${1+"$@"}'
+      func_propagate_result func_$my_func func_options
+      if $func_propagate_result_result; then
+        eval set dummy "$func_options_result"; shift
+        _G_options_quoted=:
+      fi
+    done
 
-    # save modified positional parameters for caller
-    func_options_result=$func_run_hooks_result
+    $_G_options_quoted || {
+      # As we (func_options) are top-level options-parser function and
+      # nobody quoted "$@" for us yet, we need to do it explicitly for
+      # caller.
+      func_quote eval ${1+"$@"}
+      func_options_result=$func_quote_result
+    }
 }
 
 
@@ -1649,9 +1859,8 @@
 # All initialisations required before starting the option parse loop.
 # Note that when calling hook functions, we pass through the list of
 # positional parameters.  If a hook function modifies that list, and
-# needs to propogate that back to rest of this script, then the complete
-# modified list must be put in 'func_run_hooks_result' before
-# returning.
+# needs to propagate that back to rest of this script, then the complete
+# modified list must be put in 'func_run_hooks_result' before returning.
 func_hookable func_options_prep
 func_options_prep ()
 {
@@ -1662,9 +1871,7 @@
     opt_warning_types=
 
     func_run_hooks func_options_prep ${1+"$@"}
-
-    # save modified positional parameters for caller
-    func_options_prep_result=$func_run_hooks_result
+    func_propagate_result func_run_hooks func_options_prep
 }
 
 
@@ -1676,25 +1883,32 @@
 {
     $debug_cmd
 
-    func_parse_options_result=
-
+    _G_parse_options_requote=false
     # this just eases exit handling
     while test $# -gt 0; do
       # Defer to hook functions for initial option parsing, so they
       # get priority in the event of reusing an option name.
       func_run_hooks func_parse_options ${1+"$@"}
-
-      # Adjust func_parse_options positional parameters to match
-      eval set dummy "$func_run_hooks_result"; shift
+      func_propagate_result func_run_hooks func_parse_options
+      if $func_propagate_result_result; then
+        eval set dummy "$func_parse_options_result"; shift
+        # Even though we may have changed "$@", we passed the "$@" array
+        # down into the hook and it quoted it for us (because we are in
+        # this if-branch).  No need to quote it again.
+        _G_parse_options_requote=false
+      fi
 
       # Break out of the loop if we already parsed every option.
       test $# -gt 0 || break
 
+      # We expect that one of the options parsed in this function matches
+      # and thus we remove _G_opt from "$@" and need to re-quote.
+      _G_match_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
         --debug|-x)   debug_cmd='set -x'
-                      func_echo "enabling shell trace mode"
+                      func_echo "enabling shell trace mode" >&2
                       $debug_cmd
                       ;;
 
@@ -1704,7 +1918,10 @@
 		      ;;
 
         --warnings|--warning|-W)
-                      test $# = 0 && func_missing_arg $_G_opt && break
+                      if test $# = 0 && func_missing_arg $_G_opt; then
+                        _G_parse_options_requote=:
+                        break
+                      fi
                       case " $warning_categories $1" in
                         *" $1 "*)
                           # trailing space prevents matching last $1 above
@@ -1757,15 +1974,24 @@
                       shift
                       ;;
 
-        --)           break ;;
+        --)           _G_parse_options_requote=: ; break ;;
         -*)           func_fatal_help "unrecognised option: '$_G_opt'" ;;
-        *)            set dummy "$_G_opt" ${1+"$@"}; shift; break ;;
+        *)            set dummy "$_G_opt" ${1+"$@"}; shift
+                      _G_match_parse_options=false
+                      break
+                      ;;
       esac
+
+      if $_G_match_parse_options; then
+        _G_parse_options_requote=:
+      fi
     done
 
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    func_parse_options_result=$func_quote_for_eval_result
+    if $_G_parse_options_requote; then
+      # save modified positional parameters for caller
+      func_quote eval ${1+"$@"}
+      func_parse_options_result=$func_quote_result
+    fi
 }
 
 
@@ -1782,12 +2008,10 @@
     test -n "$opt_warning_types" || opt_warning_types=" $warning_categories"
 
     func_run_hooks func_validate_options ${1+"$@"}
+    func_propagate_result func_run_hooks func_validate_options
 
     # Bail if the options were screwed!
     $exit_cmd $EXIT_FAILURE
-
-    # save modified positional parameters for caller
-    func_validate_options_result=$func_run_hooks_result
 }
 
 
@@ -1843,8 +2067,8 @@
 
 # func_split_equals STRING
 # ------------------------
-# Set func_split_equals_lhs and func_split_equals_rhs shell variables after
-# splitting STRING at the '=' sign.
+# Set func_split_equals_lhs and func_split_equals_rhs shell variables
+# after splitting STRING at the '=' sign.
 test -z "$_G_HAVE_XSI_OPS" \
     && (eval 'x=a/b/c;
       test 5aa/bb/cc = "${#x}${x%%/*}${x%/*}${x#*/}${x##*/}"') 2>/dev/null \
@@ -1859,8 +2083,9 @@
 
       func_split_equals_lhs=${1%%=*}
       func_split_equals_rhs=${1#*=}
-      test "x$func_split_equals_lhs" = "x$1" \
-        && func_split_equals_rhs=
+      if test "x$func_split_equals_lhs" = "x$1"; then
+        func_split_equals_rhs=
+      fi
   }'
 else
   # ...otherwise fall back to using expr, which is often a shell builtin.
@@ -1870,7 +2095,7 @@
 
       func_split_equals_lhs=`expr "x$1" : 'x\([^=]*\)'`
       func_split_equals_rhs=
-      test "x$func_split_equals_lhs" = "x$1" \
+      test "x$func_split_equals_lhs=" = "x$1" \
         || func_split_equals_rhs=`expr "x$1" : 'x[^=]*=\(.*\)$'`
   }
 fi #func_split_equals
@@ -1896,7 +2121,7 @@
   {
       $debug_cmd
 
-      func_split_short_opt_name=`expr "x$1" : 'x-\(.\)'`
+      func_split_short_opt_name=`expr "x$1" : 'x\(-.\)'`
       func_split_short_opt_arg=`expr "x$1" : 'x-.\(.*\)$'`
   }
 fi #func_split_short_opt
@@ -1938,31 +2163,44 @@
 # func_version
 # ------------
 # Echo version message to standard output and exit.
+# The version message is extracted from the calling file's header
+# comments, with leading '# ' stripped:
+#   1. First display the progname and version
+#   2. Followed by the header comment line matching  /^# Written by /
+#   3. Then a blank line followed by the first following line matching
+#      /^# Copyright /
+#   4. Immediately followed by any lines between the previous matches,
+#      except lines preceding the intervening completely blank line.
+# For example, see the header comments of this file.
 func_version ()
 {
     $debug_cmd
 
     printf '%s\n' "$progname $scriptversion"
     $SED -n '
-        /(C)/!b go
-        :more
-        /\./!{
-          N
-          s|\n# | |
-          b more
+        /^# Written by /!b
+        s|^# ||; p; n
+
+        :fwd2blnk
+        /./ {
+          n
+          b fwd2blnk
         }
-        :go
-        /^# Written by /,/# warranty; / {
-          s|^# ||
-          s|^# *$||
-          s|\((C)\)[ 0-9,-]*[ ,-]\([1-9][0-9]* \)|\1 \2|
-          p
+        p; n
+
+        :holdwrnt
+        s|^# ||
+        s|^# *$||
+        /^Copyright /!{
+          /./H
+          n
+          b holdwrnt
         }
-        /^# Written by / {
-          s|^# ||
-          p
-        }
-        /^warranty; /q' < "$progpath"
+
+        s|\((C)\)[ 0-9,-]*[ ,-]\([1-9][0-9]* \)|\1 \2|
+        G
+        s|\(\n\)\n*|\1|g
+        p; q' < "$progpath"
 
     exit $?
 }
@@ -1972,12 +2210,12 @@
 # mode: shell-script
 # sh-indentation: 2
 # eval: (add-hook 'before-save-hook 'time-stamp)
-# time-stamp-pattern: "10/scriptversion=%:y-%02m-%02d.%02H; # UTC"
+# time-stamp-pattern: "30/scriptversion=%:y-%02m-%02d.%02H; # UTC"
 # time-stamp-time-zone: "UTC"
 # End:
 
 # Set a version string.
-scriptversion='(GNU libtool) 2.4.6'
+scriptversion='(GNU libtool) 2.4.7'
 
 
 # func_echo ARG...
@@ -2068,7 +2306,7 @@
        compiler:       $LTCC
        compiler flags: $LTCFLAGS
        linker:         $LD (gnu? $with_gnu_ld)
-       version:        $progname (GNU libtool) 2.4.6
+       version:        $progname (GNU libtool) 2.4.7
        automake:       `($AUTOMAKE --version) 2>/dev/null |$SED 1q`
        autoconf:       `($AUTOCONF --version) 2>/dev/null |$SED 1q`
 
@@ -2124,7 +2362,7 @@
 # a configuration failure hint, and exit.
 func_fatal_configuration ()
 {
-    func__fatal_error ${1+"$@"} \
+    func_fatal_error ${1+"$@"} \
       "See the $PACKAGE documentation for more information." \
       "Fatal configuration error."
 }
@@ -2270,6 +2508,8 @@
     nonopt=
     preserve_args=
 
+    _G_rc_lt_options_prep=:
+
     # Shorthand for --mode=foo, only valid as the first argument
     case $1 in
     clean|clea|cle|cl)
@@ -2293,11 +2533,16 @@
     uninstall|uninstal|uninsta|uninst|unins|unin|uni|un|u)
       shift; set dummy --mode uninstall ${1+"$@"}; shift
       ;;
+    *)
+      _G_rc_lt_options_prep=false
+      ;;
     esac
 
-    # Pass back the list of options.
-    func_quote_for_eval ${1+"$@"}
-    libtool_options_prep_result=$func_quote_for_eval_result
+    if $_G_rc_lt_options_prep; then
+      # Pass back the list of options.
+      func_quote eval ${1+"$@"}
+      libtool_options_prep_result=$func_quote_result
+    fi
 }
 func_add_hook func_options_prep libtool_options_prep
 
@@ -2309,9 +2554,12 @@
 {
     $debug_cmd
 
+    _G_rc_lt_parse_options=false
+
     # Perform our own loop to consume as many options as possible in
     # each iteration.
     while test $# -gt 0; do
+      _G_match_lt_parse_options=:
       _G_opt=$1
       shift
       case $_G_opt in
@@ -2386,15 +2634,20 @@
                         func_append preserve_args " $_G_opt"
                         ;;
 
-	# An option not handled by this hook function:
-        *)		set dummy "$_G_opt" ${1+"$@"};	shift; break  ;;
+        # An option not handled by this hook function:
+        *)              set dummy "$_G_opt" ${1+"$@"} ; shift
+                        _G_match_lt_parse_options=false
+                        break
+                        ;;
       esac
+      $_G_match_lt_parse_options && _G_rc_lt_parse_options=:
     done
 
-
-    # save modified positional parameters for caller
-    func_quote_for_eval ${1+"$@"}
-    libtool_parse_options_result=$func_quote_for_eval_result
+    if $_G_rc_lt_parse_options; then
+      # save modified positional parameters for caller
+      func_quote eval ${1+"$@"}
+      libtool_parse_options_result=$func_quote_result
+    fi
 }
 func_add_hook func_parse_options libtool_parse_options
 
@@ -2451,8 +2704,8 @@
     }
 
     # Pass back the unparsed argument list
-    func_quote_for_eval ${1+"$@"}
-    libtool_validate_options_result=$func_quote_for_eval_result
+    func_quote eval ${1+"$@"}
+    libtool_validate_options_result=$func_quote_result
 }
 func_add_hook func_validate_options libtool_validate_options
 
@@ -3418,8 +3671,8 @@
       esac
     done
 
-    func_quote_for_eval "$libobj"
-    test "X$libobj" != "X$func_quote_for_eval_result" \
+    func_quote_arg pretty "$libobj"
+    test "X$libobj" != "X$func_quote_arg_result" \
       && $ECHO "X$libobj" | $GREP '[]~#^*{};<>?"'"'"'	 &()|`$[]' \
       && func_warning "libobj name '$libobj' may not contain shell special characters."
     func_dirname_and_basename "$obj" "/" ""
@@ -3492,8 +3745,8 @@
 
     func_to_tool_file "$srcfile" func_convert_file_msys_to_w32
     srcfile=$func_to_tool_file_result
-    func_quote_for_eval "$srcfile"
-    qsrcfile=$func_quote_for_eval_result
+    func_quote_arg pretty "$srcfile"
+    qsrcfile=$func_quote_arg_result
 
     # Only build a PIC object if we are building libtool libraries.
     if test yes = "$build_libtool_libs"; then
@@ -3648,7 +3901,8 @@
   -prefer-non-pic   try to build non-PIC objects only
   -shared           do not build a '.o' file suitable for static linking
   -static           only build a '.o' file suitable for static linking
-  -Wc,FLAG          pass FLAG directly to the compiler
+  -Wc,FLAG
+  -Xcompiler FLAG   pass FLAG directly to the compiler
 
 COMPILE-COMMAND is a command to be used in creating a 'standard' object file
 from the given SOURCEFILE.
@@ -3754,6 +4008,8 @@
   -weak LIBNAME     declare that the target provides the LIBNAME interface
   -Wc,FLAG
   -Xcompiler FLAG   pass linker-specific FLAG directly to the compiler
+  -Wa,FLAG
+  -Xassembler FLAG  pass linker-specific FLAG directly to the assembler
   -Wl,FLAG
   -Xlinker FLAG     pass linker-specific FLAG directly to the linker
   -XCClinker FLAG   pass link-specific FLAG to the compiler driver (CC)
@@ -4096,8 +4352,8 @@
        case $nonopt in *shtool*) :;; *) false;; esac
     then
       # Aesthetically quote it.
-      func_quote_for_eval "$nonopt"
-      install_prog="$func_quote_for_eval_result "
+      func_quote_arg pretty "$nonopt"
+      install_prog="$func_quote_arg_result "
       arg=$1
       shift
     else
@@ -4107,8 +4363,8 @@
 
     # The real first argument should be the name of the installation program.
     # Aesthetically quote it.
-    func_quote_for_eval "$arg"
-    func_append install_prog "$func_quote_for_eval_result"
+    func_quote_arg pretty "$arg"
+    func_append install_prog "$func_quote_arg_result"
     install_shared_prog=$install_prog
     case " $install_prog " in
       *[\\\ /]cp\ *) install_cp=: ;;
@@ -4165,12 +4421,12 @@
       esac
 
       # Aesthetically quote the argument.
-      func_quote_for_eval "$arg"
-      func_append install_prog " $func_quote_for_eval_result"
+      func_quote_arg pretty "$arg"
+      func_append install_prog " $func_quote_arg_result"
       if test -n "$arg2"; then
-	func_quote_for_eval "$arg2"
+	func_quote_arg pretty "$arg2"
       fi
-      func_append install_shared_prog " $func_quote_for_eval_result"
+      func_append install_shared_prog " $func_quote_arg_result"
     done
 
     test -z "$install_prog" && \
@@ -4181,8 +4437,8 @@
 
     if test -n "$install_override_mode" && $no_mode; then
       if $install_cp; then :; else
-	func_quote_for_eval "$install_override_mode"
-	func_append install_shared_prog " -m $func_quote_for_eval_result"
+	func_quote_arg pretty "$install_override_mode"
+	func_append install_shared_prog " -m $func_quote_arg_result"
       fi
     fi
 
@@ -4478,8 +4734,8 @@
 	        relink_command=`$ECHO "$relink_command" | $SED 's%@OUTPUT@%'"$outputname"'%g'`
 
 	        $opt_quiet || {
-	          func_quote_for_expand "$relink_command"
-		  eval "func_echo $func_quote_for_expand_result"
+	          func_quote_arg expand,pretty "$relink_command"
+		  eval "func_echo $func_quote_arg_result"
 	        }
 	        if eval "$relink_command"; then :
 	          else
@@ -5258,7 +5514,8 @@
   if test \"\$libtool_execute_magic\" != \"$magic\"; then
     file=\"\$0\""
 
-    qECHO=`$ECHO "$ECHO" | $SED "$sed_quote_subst"`
+    func_quote_arg pretty "$ECHO"
+    qECHO=$func_quote_arg_result
     $ECHO "\
 
 # A function that is used when there is no print builtin or printf.
@@ -5268,7 +5525,7 @@
 \$1
 _LTECHO_EOF'
 }
-    ECHO=\"$qECHO\"
+    ECHO=$qECHO
   fi
 
 # Very basic option parsing. These options are (a) specific to
@@ -6611,9 +6868,9 @@
     while test "$#" -gt 0; do
       arg=$1
       shift
-      func_quote_for_eval "$arg"
-      qarg=$func_quote_for_eval_unquoted_result
-      func_append libtool_args " $func_quote_for_eval_result"
+      func_quote_arg pretty,unquoted "$arg"
+      qarg=$func_quote_arg_unquoted_result
+      func_append libtool_args " $func_quote_arg_result"
 
       # If the previous option needs an argument, assign it.
       if test -n "$prev"; then
@@ -6849,6 +7106,13 @@
 	  prev=
 	  continue
 	  ;;
+	xassembler)
+	  func_append compiler_flags " -Xassembler $qarg"
+	  prev=
+	  func_append compile_command " -Xassembler $qarg"
+	  func_append finalize_command " -Xassembler $qarg"
+	  continue
+	  ;;
 	xcclinker)
 	  func_append linker_flags " $qarg"
 	  func_append compiler_flags " $qarg"
@@ -7019,7 +7283,7 @@
 	    # These systems don't actually have a C library (as such)
 	    test X-lc = "X$arg" && continue
 	    ;;
-	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig*)
+	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig* | *-*-midnightbsd*)
 	    # Do not include libc due to us having libc/libc_r.
 	    test X-lc = "X$arg" && continue
 	    ;;
@@ -7039,7 +7303,7 @@
 	  esac
 	elif test X-lc_r = "X$arg"; then
 	 case $host in
-	 *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig*)
+	 *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-bitrig* | *-*-midnightbsd*)
 	   # Do not include libc_r directly, use -pthread flag.
 	   continue
 	   ;;
@@ -7069,8 +7333,20 @@
 	prev=xcompiler
 	continue
 	;;
-
-      -mt|-mthreads|-kthread|-Kthread|-pthread|-pthreads|--thread-safe \
+     # Solaris ld rejects as of 11.4. Refer to Oracle bug 22985199.
+     -pthread)
+	case $host in
+	  *solaris2*) ;;
+	  *)
+	    case "$new_inherited_linker_flags " in
+	        *" $arg "*) ;;
+	        * ) func_append new_inherited_linker_flags " $arg" ;;
+	    esac
+	  ;;
+	esac
+	continue
+	;;
+      -mt|-mthreads|-kthread|-Kthread|-pthreads|--thread-safe \
       |-threads|-fopenmp|-openmp|-mp|-xopenmp|-omp|-qsmp=*)
 	func_append compiler_flags " $arg"
 	func_append compile_command " $arg"
@@ -7211,9 +7487,9 @@
 	save_ifs=$IFS; IFS=,
 	for flag in $args; do
 	  IFS=$save_ifs
-          func_quote_for_eval "$flag"
-	  func_append arg " $func_quote_for_eval_result"
-	  func_append compiler_flags " $func_quote_for_eval_result"
+          func_quote_arg pretty "$flag"
+	  func_append arg " $func_quote_arg_result"
+	  func_append compiler_flags " $func_quote_arg_result"
 	done
 	IFS=$save_ifs
 	func_stripname ' ' '' "$arg"
@@ -7227,16 +7503,21 @@
 	save_ifs=$IFS; IFS=,
 	for flag in $args; do
 	  IFS=$save_ifs
-          func_quote_for_eval "$flag"
-	  func_append arg " $wl$func_quote_for_eval_result"
-	  func_append compiler_flags " $wl$func_quote_for_eval_result"
-	  func_append linker_flags " $func_quote_for_eval_result"
+          func_quote_arg pretty "$flag"
+	  func_append arg " $wl$func_quote_arg_result"
+	  func_append compiler_flags " $wl$func_quote_arg_result"
+	  func_append linker_flags " $func_quote_arg_result"
 	done
 	IFS=$save_ifs
 	func_stripname ' ' '' "$arg"
 	arg=$func_stripname_result
 	;;
 
+      -Xassembler)
+        prev=xassembler
+        continue
+        ;;
+
       -Xcompiler)
 	prev=xcompiler
 	continue
@@ -7254,8 +7535,8 @@
 
       # -msg_* for osf cc
       -msg_*)
-	func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+	func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
 
       # Flags to be passed through unchanged, with rationale:
@@ -7272,12 +7553,17 @@
       # -tp=*                Portland pgcc target processor selection
       # --sysroot=*          for sysroot support
       # -O*, -g*, -flto*, -fwhopr*, -fuse-linker-plugin GCC link-time optimization
+      # -specs=*             GCC specs files
       # -stdlib=*            select c++ std lib with clang
+      # -fsanitize=*         Clang/GCC memory and address sanitizer
+      # -fuse-ld=*           Linker select flags for GCC
+      # -Wa,*                Pass flags directly to the assembler
       -64|-mips[0-9]|-r[0-9][0-9]*|-xarch=*|-xtarget=*|+DA*|+DD*|-q*|-m*| \
       -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*|--sysroot=*| \
-      -O*|-g*|-flto*|-fwhopr*|-fuse-linker-plugin|-fstack-protector*|-stdlib=*)
-        func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+      -O*|-g*|-flto*|-fwhopr*|-fuse-linker-plugin|-fstack-protector*|-stdlib=*| \
+      -specs=*|-fsanitize=*|-fuse-ld=*|-Wa,*)
+        func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
         func_append compile_command " $arg"
         func_append finalize_command " $arg"
         func_append compiler_flags " $arg"
@@ -7298,15 +7584,15 @@
 	  continue
         else
 	  # Otherwise treat like 'Some other compiler flag' below
-	  func_quote_for_eval "$arg"
-	  arg=$func_quote_for_eval_result
+	  func_quote_arg pretty "$arg"
+	  arg=$func_quote_arg_result
         fi
 	;;
 
       # Some other compiler flag.
       -* | +*)
-        func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+        func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
 
       *.$objext)
@@ -7426,8 +7712,8 @@
       *)
 	# Unknown arguments in both finalize_command and compile_command need
 	# to be aesthetically quoted because they are evaled later.
-	func_quote_for_eval "$arg"
-	arg=$func_quote_for_eval_result
+	func_quote_arg pretty "$arg"
+	arg=$func_quote_arg_result
 	;;
       esac # arg
 
@@ -8632,7 +8918,7 @@
       test CXX = "$tagname" && {
         case $host_os in
         linux*)
-          case `$CC -V 2>&1 | sed 5q` in
+          case `$CC -V 2>&1 | $SED 5q` in
           *Sun\ C*) # Sun C++ 5.9
             func_suncc_cstd_abi
 
@@ -8805,7 +9091,7 @@
 	  #
 	  case $version_type in
 	  # correct linux to gnu/linux during the next big refactor
-	  darwin|freebsd-elf|linux|osf|windows|none)
+	  darwin|freebsd-elf|linux|midnightbsd-elf|osf|windows|none)
 	    func_arith $number_major + $number_minor
 	    current=$func_arith_result
 	    age=$number_minor
@@ -8896,7 +9182,7 @@
 	  versuffix=.$current.$revision
 	  ;;
 
-	freebsd-elf)
+	freebsd-elf | midnightbsd-elf)
 	  func_arith $current - $age
 	  major=.$func_arith_result
 	  versuffix=$major.$age.$revision
@@ -9122,7 +9408,7 @@
 	  *-*-netbsd*)
 	    # Don't link with libc until the a.out ld.so is fixed.
 	    ;;
-	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly*)
+	  *-*-openbsd* | *-*-freebsd* | *-*-dragonfly* | *-*-midnightbsd*)
 	    # Do not include libc due to us having libc/libc_r.
 	    ;;
 	  *-*-sco3.2v5* | *-*-sco5v6*)
@@ -9933,8 +10219,8 @@
 	    for cmd in $concat_cmds; do
 	      IFS=$save_ifs
 	      $opt_quiet || {
-		  func_quote_for_expand "$cmd"
-		  eval "func_echo $func_quote_for_expand_result"
+		  func_quote_arg expand,pretty "$cmd"
+		  eval "func_echo $func_quote_arg_result"
 	      }
 	      $opt_dry_run || eval "$cmd" || {
 		lt_exit=$?
@@ -10027,8 +10313,8 @@
 	  eval cmd=\"$cmd\"
 	  IFS=$save_ifs
 	  $opt_quiet || {
-	    func_quote_for_expand "$cmd"
-	    eval "func_echo $func_quote_for_expand_result"
+	    func_quote_arg expand,pretty "$cmd"
+	    eval "func_echo $func_quote_arg_result"
 	  }
 	  $opt_dry_run || eval "$cmd" || {
 	    lt_exit=$?
@@ -10502,12 +10788,13 @@
 	  elif eval var_value=\$$var; test -z "$var_value"; then
 	    relink_command="$var=; export $var; $relink_command"
 	  else
-	    func_quote_for_eval "$var_value"
-	    relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
+	    func_quote_arg pretty "$var_value"
+	    relink_command="$var=$func_quote_arg_result; export $var; $relink_command"
 	  fi
 	done
-	relink_command="(cd `pwd`; $relink_command)"
-	relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+	func_quote eval cd "`pwd`"
+	func_quote_arg pretty,unquoted "($func_quote_result; $relink_command)"
+	relink_command=$func_quote_arg_unquoted_result
       fi
 
       # Only actually do things if not in dry run mode.
@@ -10747,13 +11034,15 @@
 	elif eval var_value=\$$var; test -z "$var_value"; then
 	  relink_command="$var=; export $var; $relink_command"
 	else
-	  func_quote_for_eval "$var_value"
-	  relink_command="$var=$func_quote_for_eval_result; export $var; $relink_command"
+	  func_quote_arg pretty,unquoted "$var_value"
+	  relink_command="$var=$func_quote_arg_unquoted_result; export $var; $relink_command"
 	fi
       done
       # Quote the link command for shipping.
-      relink_command="(cd `pwd`; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
-      relink_command=`$ECHO "$relink_command" | $SED "$sed_quote_subst"`
+      func_quote eval cd "`pwd`"
+      relink_command="($func_quote_result; $SHELL \"$progpath\" $preserve_args --mode=relink $libtool_args @inst_prefix_dir@)"
+      func_quote_arg pretty,unquoted "$relink_command"
+      relink_command=$func_quote_arg_unquoted_result
       if test yes = "$hardcode_automatic"; then
 	relink_command=
       fi
diff --git a/mips/filter_mmi_inline_assembly.c b/mips/filter_mmi_inline_assembly.c
new file mode 100644
index 0000000..b330a46
--- /dev/null
+++ b/mips/filter_mmi_inline_assembly.c
@@ -0,0 +1,525 @@
+/* filter_mmi_intrinsics.c - MMI optimized filter functions
+ *
+ * Copyright (c) 2024 Cosmin Truta
+ * Written by zhanglixia and guxiwei, 2023
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "../pngpriv.h"
+
+#ifdef PNG_READ_SUPPORTED
+
+#if PNG_MIPS_MMI_IMPLEMENTATION == 2 /* Inline Assembly */
+
+/* Functions in this file look at most 3 pixels (a,b,c) to predict the 4th (d).
+ * They're positioned like this:
+ *    prev:  c b
+ *    row:   a d
+ * The Sub filter predicts d=a, Avg d=(a+b)/2, and Paeth predicts d to be
+ * whichever of a, b, or c is closest to p=a+b-c.
+ */
+
+void png_read_filter_row_up_mmi(png_row_infop row_info, png_bytep row,
+                                png_const_bytep prev_row)
+{
+   int istop = row_info->rowbytes;
+   double rp,pp;
+   __asm__ volatile (
+       "1:                                          \n\t"
+       "ldc1   %[rp],       0x00(%[row])            \n\t"
+       "ldc1   %[pp],       0x00(%[prev_row])       \n\t"
+       "paddb  %[rp],       %[rp],            %[pp] \n\t"
+       "sdc1   %[rp],       0x00(%[row])            \n\t"
+
+       "daddiu %[row],      %[row],           0x08  \n\t"
+       "daddiu %[prev_row], %[prev_row],      0x08  \n\t"
+       "daddiu %[istop],    %[istop],        -0x08  \n\t"
+       "bgtz   %[istop],    1b                      \n\t"
+       : [rp]"=&f"(rp), [pp]"=&f"(pp)
+       : [row]"r"(row), [prev_row]"r"(prev_row),
+         [istop]"r"(istop)
+       : "memory"
+   );
+}
+
+void png_read_filter_row_sub3_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   int istop = row_info->rowbytes;
+   double rp, pp, dest;
+   double eight, sixteen, twenty_four, forty_eight;
+   double tmp0;
+   double ftmp[2];
+
+   __asm__ volatile (
+        "li         %[tmp0],    0x08                          \n\t"
+        "dmtc1      %[tmp0],    %[eight]                      \n\t"
+        "li         %[tmp0],    0x10                          \n\t"
+        "dmtc1      %[tmp0],    %[sixteen]                    \n\t"
+        "li         %[tmp0],    0x18                          \n\t"
+        "dmtc1      %[tmp0],    %[twenty_four]                \n\t"
+        "li         %[tmp0],    0x30                          \n\t"
+        "dmtc1      %[tmp0],    %[forty_eight]                \n\t"
+        "xor        %[dest],    %[dest],       %[dest]        \n\t"
+
+        "1:                                                   \n\t"
+        "gsldrc1    %[rp],      0x00(%[row])                  \n\t"
+        "gsldlc1    %[rp],      0x07(%[row])                  \n\t"
+        "gsldrc1    %[pp],      0x08(%[row])                  \n\t"
+        "gsldlc1    %[pp],      0x0f(%[row])                  \n\t"
+
+        "paddb      %[ftmp0],   %[dest],      %[rp]           \n\t"
+        "swc1       %[ftmp0],   0x00(%[row])                  \n\t"
+
+        "dsrl       %[ftmp1],   %[rp],        %[twenty_four]  \n\t"
+        "paddb      %[dest],    %[ftmp1],     %[ftmp0]        \n\t"
+        "gsswrc1    %[dest],    0x03(%[row])                  \n\t"
+        "gsswlc1    %[dest],    0x06(%[row])                  \n\t"
+
+        "dsrl       %[ftmp0],   %[rp],        %[forty_eight]  \n\t"
+        "dsll       %[ftmp1],   %[pp],        %[sixteen]      \n\t"
+        "or         %[ftmp0],   %[ftmp0],     %[ftmp1]        \n\t"
+        "paddb      %[dest],    %[dest],      %[ftmp0]        \n\t"
+        "gsswrc1    %[dest],    0x06(%[row])                  \n\t"
+        "gsswlc1    %[dest],    0x09(%[row])                  \n\t"
+
+        "dsrl       %[ftmp0],   %[pp],        %[eight]        \n\t"
+        "paddb      %[dest],    %[dest],      %[ftmp0]        \n\t"
+        "gsswrc1    %[dest],    0x09(%[row])                  \n\t"
+        "daddiu     %[row],     %[row],       0x0c            \n\t"
+        "daddiu     %[istop],   %[istop],    -0x0c            \n\t"
+        "bgtz       %[istop],   1b                            \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp), [dest]"=&f"(dest),
+          [tmp0]"=&r"(tmp0), [ftmp0]"=&f"(ftmp[0]),
+          [ftmp1]"=&f"(ftmp[1]), [eight]"=&f"(eight),
+          [sixteen]"=&f"(sixteen), [twenty_four]"=&f"(twenty_four),
+          [forty_eight]"=&f"(forty_eight)
+        : [row]"r"(row), [istop]"r"(istop)
+        : "memory"
+   );
+
+   PNG_UNUSED(prev)
+}
+
+void png_read_filter_row_sub4_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   /* The Sub filter predicts each pixel as the previous pixel, a.
+    * There is no pixel to the left of the first pixel.  It's encoded directly.
+    * That works with our main loop if we just say that left pixel was zero.
+    */
+   int istop = row_info->rowbytes;
+   double rp,pp;
+
+   __asm__ volatile (
+        "1:                                          \n\t"
+        "lwc1   %[pp],       0x00(%[row])            \n\t"
+        "lwc1   %[rp],       0x04(%[row])            \n\t"
+        "paddb  %[rp],       %[rp],       %[pp]      \n\t"
+        "swc1   %[rp],       0x04(%[row])            \n\t"
+
+        "daddiu %[row],      %[row],      0x04       \n\t"
+        "daddiu %[istop],    %[istop],   -0x04       \n\t"
+        "bgtz   %[istop],    1b                      \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp)
+        : [row]"r"(row), [istop]"r"(istop)
+        : "memory"
+   );
+
+   PNG_UNUSED(prev)
+}
+
+void png_read_filter_row_avg3_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   int istop = row_info->rowbytes;
+   double rp, pp, rp1, pp1;
+   double tmp0;
+   double ftmp[3];
+   double one, dest;
+   double eight, sixteen, twenty_four, forty_eight;
+
+   __asm__ volatile (
+        "li         %[tmp0],    0x08                          \n\t"
+        "dmtc1      %[tmp0],    %[eight]                      \n\t"
+        "li         %[tmp0],    0x10                          \n\t"
+        "dmtc1      %[tmp0],    %[sixteen]                    \n\t"
+        "li         %[tmp0],    0x18                          \n\t"
+        "dmtc1      %[tmp0],    %[twenty_four]                \n\t"
+        "li         %[tmp0],    0x30                          \n\t"
+        "dmtc1      %[tmp0],    %[forty_eight]                \n\t"
+        "xor        %[dest],    %[dest],       %[dest]        \n\t"
+
+        "li         %[tmp0],   0x01                           \n\t"
+        "ins        %[tmp0],   %[tmp0],        8,   8         \n\t"
+        "dmtc1      %[tmp0],   %[one]                         \n\t"
+        "pshufh     %[one],    %[one],         %[dest]        \n\t"
+
+        "1:                                                   \n\t"
+        "gsldrc1    %[rp],      0x00(%[row])                  \n\t"
+        "gsldlc1    %[rp],      0x07(%[row])                  \n\t"
+        "gsldrc1    %[pp],      0x00(%[prev])                 \n\t"
+        "gsldlc1    %[pp],      0x07(%[prev])                 \n\t"
+        "gsldrc1    %[rp1],     0x08(%[row])                  \n\t"
+        "gsldlc1    %[rp1],     0x0f(%[row])                  \n\t"
+        "gsldrc1    %[pp1],     0x08(%[prev])                 \n\t"
+        "gsldlc1    %[pp1],     0x0f(%[prev])                 \n\t"
+
+        "xor        %[ftmp0],   %[pp],         %[dest]        \n\t"
+        "pavgb      %[ftmp1],   %[pp],         %[dest]        \n\t"
+        "and        %[ftmp0],   %[ftmp0],      %[one]         \n\t"
+        "psubb      %[ftmp1],   %[ftmp1],      %[ftmp0]       \n\t"
+        "paddb      %[dest],    %[rp],         %[ftmp1]       \n\t"
+        "swc1       %[dest],    0x00(%[row])                  \n\t"
+
+        "dsrl       %[ftmp0],   %[rp],         %[twenty_four] \n\t"
+        "dsrl       %[ftmp1],   %[pp],         %[twenty_four] \n\t"
+
+        "xor        %[ftmp2],   %[ftmp1],      %[dest]        \n\t"
+        "pavgb      %[ftmp1],   %[ftmp1],      %[dest]        \n\t"
+        "and        %[ftmp2],   %[ftmp2],      %[one]         \n\t"
+        "psubb      %[ftmp1],   %[ftmp1],      %[ftmp2]       \n\t"
+        "paddb      %[dest],    %[ftmp0],      %[ftmp1]       \n\t"
+        "gsswrc1    %[dest],    0x03(%[row])                  \n\t"
+        "gsswlc1    %[dest],    0x06(%[row])                  \n\t"
+
+        "dsrl       %[ftmp0],   %[rp],         %[forty_eight] \n\t"
+        "dsll       %[ftmp1],   %[rp1],        %[sixteen]     \n\t"
+        "or         %[ftmp0],   %[ftmp0],      %[ftmp1]       \n\t"
+        "dsrl       %[ftmp2],   %[pp],         %[forty_eight] \n\t"
+        "dsll       %[ftmp1],   %[pp1],        %[sixteen]     \n\t"
+        "or         %[ftmp1],   %[ftmp2],      %[ftmp1]       \n\t"
+
+        "xor        %[ftmp2],   %[ftmp1],      %[dest]        \n\t"
+        "pavgb      %[ftmp1],   %[ftmp1],      %[dest]        \n\t"
+        "and        %[ftmp2],   %[ftmp2],      %[one]         \n\t"
+        "psubb      %[ftmp1],   %[ftmp1],      %[ftmp2]       \n\t"
+        "paddb      %[dest],    %[ftmp0],      %[ftmp1]       \n\t"
+        "gsswrc1    %[dest],    0x06(%[row])                  \n\t"
+        "gsswlc1    %[dest],    0x09(%[row])                  \n\t"
+
+        "dsrl       %[ftmp0],   %[rp1],        %[eight]       \n\t"
+        "dsrl       %[ftmp1],   %[pp1],        %[eight]       \n\t"
+
+        "xor        %[ftmp2],   %[ftmp1],      %[dest]        \n\t"
+        "pavgb      %[ftmp1],   %[ftmp1],      %[dest]        \n\t"
+        "and        %[ftmp2],   %[ftmp2],      %[one]         \n\t"
+        "psubb      %[ftmp1],   %[ftmp1],      %[ftmp2]       \n\t"
+        "paddb      %[dest],    %[ftmp0],      %[ftmp1]       \n\t"
+        "gsswrc1    %[dest],    0x09(%[row])                  \n\t"
+        "daddiu     %[row],     %[row],        0x0c           \n\t"
+        "daddiu     %[prev],    %[prev],       0x0c           \n\t"
+        "daddiu     %[istop],   %[istop],     -0x0c           \n\t"
+        "bgtz       %[istop],   1b                            \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp), [rp1]"=&f"(rp1),
+          [pp1]"=&f"(pp1), [tmp0]"=&r"(tmp0), [ftmp0]"=&f"(ftmp[0]),
+          [ftmp1]"=&f"(ftmp[1]), [ftmp2]"=&f"(ftmp[2]), [one]"=&f"(one),
+          [dest]"=&f"(dest), [eight]"=&f"(eight), [sixteen]"=&f"(sixteen),
+          [twenty_four]"=&f"(twenty_four), [forty_eight]"=&f"(forty_eight)
+        : [row]"r"(row), [prev]"r"(prev), [istop]"r"(istop)
+        : "memory"
+   );
+}
+
+void png_read_filter_row_avg4_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   int istop = row_info->rowbytes;
+   double rp,pp;
+   double dest;
+   double ftmp[2];
+   double tmp;
+
+   __asm__ volatile (
+        "xor        %[dest],   %[dest],       %[dest]  \n\t"
+        "li         %[tmp],    0x01                    \n\t"
+        "ins        %[tmp],    %[tmp],        8,  8    \n\t"
+        "dmtc1      %[tmp],    %[ftmp1]                \n\t"
+        "pshufh     %[ftmp1],  %[ftmp1],      %[dest]  \n\t"
+
+        "1:                                            \n\t"
+        "lwc1       %[rp],     0x00(%[row])            \n\t"
+        "lwc1       %[pp],     0x00(%[prev])           \n\t"
+        "xor        %[ftmp0],  %[pp],         %[dest]  \n\t"
+        "pavgb      %[pp],     %[pp],         %[dest]  \n\t"
+        "and        %[ftmp0],  %[ftmp0],      %[ftmp1] \n\t"
+        "psubb      %[pp],     %[pp],         %[ftmp0] \n\t"
+        "paddb      %[dest],   %[rp],         %[pp]    \n\t"
+        "swc1       %[dest],   0x00(%[row])            \n\t"
+        "daddiu     %[row],    %[row],        0x04     \n\t"
+        "daddiu     %[prev],   %[prev],       0x04     \n\t"
+        "daddiu     %[istop],  %[istop],     -0x04     \n\t"
+        "bgtz       %[istop],  1b                      \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp), [ftmp0]"=&f"(ftmp[0]),
+          [ftmp1]"=&f"(ftmp[1]), [dest]"=&f"(dest), [tmp]"=&r"(tmp)
+        : [row]"r"(row), [prev]"r"(prev), [istop]"r"(istop)
+        : "memory"
+   );
+}
+
+void png_read_filter_row_paeth3_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   /* Paeth tries to predict pixel d using the pixel to the left of it, a,
+    * and two pixels from the previous row, b and c:
+    *   prev: c b
+    *   row:  a d
+    * The Paeth function predicts d to be whichever of a, b, or c is nearest to
+    * p=a+b-c.
+    *
+    * The first pixel has no left context, and so uses an Up filter, p = b.
+    * This works naturally with our main loop's p = a+b-c if we force a and c
+    * to zero.
+    * Here we zero b and d, which become c and a respectively at the start of
+    * the loop.
+    */
+   int istop = row_info->rowbytes;
+   double rp, pp, rp1, pp1, zero;
+   double a, b, c, d, pa, pb, pc;
+   double tmp0;
+   double ftmp[3];
+   double eight, sixteen, twenty_four, forty_eight;
+
+   __asm__ volatile (
+        "xor        %[a],      %[a],           %[a]           \n\t"
+        "xor        %[c],      %[c],           %[c]           \n\t"
+        "xor        %[zero],   %[zero],        %[zero]        \n\t"
+        "li         %[tmp0],    0x08                          \n\t"
+        "dmtc1      %[tmp0],    %[eight]                      \n\t"
+        "li         %[tmp0],    0x10                          \n\t"
+        "dmtc1      %[tmp0],    %[sixteen]                    \n\t"
+        "li         %[tmp0],    0x18                          \n\t"
+        "dmtc1      %[tmp0],    %[twenty_four]                \n\t"
+        "li         %[tmp0],    0x30                          \n\t"
+        "dmtc1      %[tmp0],    %[forty_eight]                \n\t"
+
+        "1:                                                   \n\t"
+        "gsldrc1    %[rp],      0x00(%[row])                  \n\t"
+        "gsldlc1    %[rp],      0x07(%[row])                  \n\t"
+        "gsldrc1    %[pp],      0x00(%[prev])                 \n\t"
+        "gsldlc1    %[pp],      0x07(%[prev])                 \n\t"
+        "gsldrc1    %[rp1],     0x08(%[row])                  \n\t"
+        "gsldlc1    %[rp1],     0x0f(%[row])                  \n\t"
+        "gsldrc1    %[pp1],     0x08(%[prev])                 \n\t"
+        "gsldlc1    %[pp1],     0x0f(%[prev])                 \n\t"
+
+        "punpcklbh  %[b],      %[pp],          %[zero]        \n\t"
+        "punpcklbh  %[d],      %[rp],          %[zero]        \n\t"
+        "packushb   %[ftmp0],  %[c],           %[c]           \n\t"
+        "packushb   %[ftmp1],  %[a],           %[a]           \n\t"
+        "pasubub    %[pa],     %[pp],          %[ftmp0]       \n\t"
+        "pasubub    %[pb],     %[ftmp1],       %[ftmp0]       \n\t"
+        "psubh      %[ftmp0],  %[b],           %[c]           \n\t"
+        "psubh      %[ftmp1],  %[a],           %[c]           \n\t"
+        "paddh      %[pc],     %[ftmp0],       %[ftmp1]       \n\t"
+        "pcmpgth    %[ftmp0],  %[zero],        %[pc]          \n\t"
+        "xor        %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "psubh      %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "punpcklbh  %[pa],     %[pa],          %[zero]        \n\t"
+        "punpcklbh  %[pb],     %[pb],          %[zero]        \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pb]          \n\t"
+        "and        %[ftmp1],  %[b],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "pminsh     %[pa],     %[pa],          %[pb]          \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pc]          \n\t"
+        "and        %[ftmp1],  %[c],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "paddb      %[a],      %[a],           %[d]           \n\t"
+        "packushb   %[d],      %[a],           %[a]           \n\t"
+        "punpcklbh  %[c],      %[pp],          %[zero]        \n\t"
+        "swc1       %[d],      0x00(%[row])                   \n\t"
+
+        "dsrl       %[ftmp0],  %[rp],          %[twenty_four] \n\t"
+        "dsrl       %[ftmp2],  %[pp],          %[twenty_four] \n\t"
+
+        "punpcklbh  %[b],      %[ftmp2],       %[zero]        \n\t"
+        "punpcklbh  %[d],      %[ftmp0],       %[zero]        \n\t"
+        "packushb   %[ftmp0],  %[c],           %[c]           \n\t"
+        "packushb   %[ftmp1],  %[a],           %[a]           \n\t"
+        "pasubub    %[pa],     %[ftmp2],       %[ftmp0]       \n\t"
+        "pasubub    %[pb],     %[ftmp1],       %[ftmp0]       \n\t"
+        "psubh      %[ftmp0],  %[b],           %[c]           \n\t"
+        "psubh      %[ftmp1],  %[a],           %[c]           \n\t"
+        "paddh      %[pc],     %[ftmp0],       %[ftmp1]       \n\t"
+        "pcmpgth    %[ftmp0],  %[zero],        %[pc]          \n\t"
+        "xor        %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "psubh      %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "punpcklbh  %[pa],     %[pa],          %[zero]        \n\t"
+        "punpcklbh  %[pb],     %[pb],          %[zero]        \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pb]          \n\t"
+        "and        %[ftmp1],  %[b],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "pminsh     %[pa],     %[pa],          %[pb]          \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pc]          \n\t"
+        "and        %[ftmp1],  %[c],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "paddb      %[a],      %[a],           %[d]           \n\t"
+        "packushb   %[d],      %[a],           %[a]           \n\t"
+        "punpcklbh  %[c],      %[ftmp2],       %[zero]        \n\t"
+        "gsswrc1    %[d],      0x03(%[row])                   \n\t"
+        "gsswlc1    %[d],      0x06(%[row])                   \n\t"
+
+        "dsrl       %[ftmp0],  %[rp],          %[forty_eight] \n\t"
+        "dsll       %[ftmp1],  %[rp1],         %[sixteen]     \n\t"
+        "or         %[ftmp0],  %[ftmp0],       %[ftmp1]       \n\t"
+        "dsrl       %[ftmp2],  %[pp],          %[forty_eight] \n\t"
+        "dsll       %[ftmp1],  %[pp1],         %[sixteen]     \n\t"
+        "or         %[ftmp2],  %[ftmp2],       %[ftmp1]       \n\t"
+
+        "punpcklbh  %[b],      %[ftmp2],       %[zero]        \n\t"
+        "punpcklbh  %[d],      %[ftmp0],       %[zero]        \n\t"
+        "packushb   %[ftmp0],  %[c],           %[c]           \n\t"
+        "packushb   %[ftmp1],  %[a],           %[a]           \n\t"
+        "pasubub    %[pa],     %[ftmp2],       %[ftmp0]       \n\t"
+        "pasubub    %[pb],     %[ftmp1],       %[ftmp0]       \n\t"
+        "psubh      %[ftmp0],  %[b],           %[c]           \n\t"
+        "psubh      %[ftmp1],  %[a],           %[c]           \n\t"
+        "paddh      %[pc],     %[ftmp0],       %[ftmp1]       \n\t"
+        "pcmpgth    %[ftmp0],  %[zero],        %[pc]          \n\t"
+        "xor        %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "psubh      %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "punpcklbh  %[pa],     %[pa],          %[zero]        \n\t"
+        "punpcklbh  %[pb],     %[pb],          %[zero]        \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pb]          \n\t"
+        "and        %[ftmp1],  %[b],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "pminsh     %[pa],     %[pa],          %[pb]          \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pc]          \n\t"
+        "and        %[ftmp1],  %[c],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "paddb      %[a],      %[a],           %[d]           \n\t"
+        "packushb   %[d],      %[a],           %[a]           \n\t"
+        "punpcklbh  %[c],      %[ftmp2],       %[zero]        \n\t"
+        "gsswrc1    %[d],      0x06(%[row])                   \n\t"
+        "gsswlc1    %[d],      0x09(%[row])                   \n\t"
+
+        "dsrl       %[ftmp0],   %[rp1],        %[eight]       \n\t"
+        "dsrl       %[ftmp2],   %[pp1],        %[eight]       \n\t"
+
+        "punpcklbh  %[b],      %[ftmp2],       %[zero]        \n\t"
+        "punpcklbh  %[d],      %[ftmp0],       %[zero]        \n\t"
+        "packushb   %[ftmp0],  %[c],           %[c]           \n\t"
+        "packushb   %[ftmp1],  %[a],           %[a]           \n\t"
+        "pasubub    %[pa],     %[ftmp2],       %[ftmp0]       \n\t"
+        "pasubub    %[pb],     %[ftmp1],       %[ftmp0]       \n\t"
+        "psubh      %[ftmp0],  %[b],           %[c]           \n\t"
+        "psubh      %[ftmp1],  %[a],           %[c]           \n\t"
+        "paddh      %[pc],     %[ftmp0],       %[ftmp1]       \n\t"
+        "pcmpgth    %[ftmp0],  %[zero],        %[pc]          \n\t"
+        "xor        %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "psubh      %[pc],     %[pc],          %[ftmp0]       \n\t"
+        "punpcklbh  %[pa],     %[pa],          %[zero]        \n\t"
+        "punpcklbh  %[pb],     %[pb],          %[zero]        \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pb]          \n\t"
+        "and        %[ftmp1],  %[b],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "pminsh     %[pa],     %[pa],          %[pb]          \n\t"
+        "pcmpgth    %[ftmp0],  %[pa],          %[pc]          \n\t"
+        "and        %[ftmp1],  %[c],           %[ftmp0]       \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]           \n\t"
+        "or         %[a],      %[a],           %[ftmp1]       \n\t"
+        "paddb      %[a],      %[a],           %[d]           \n\t"
+        "packushb   %[d],      %[a],           %[a]           \n\t"
+        "punpcklbh  %[c],      %[ftmp2],       %[zero]        \n\t"
+        "gsswrc1    %[d],      0x09(%[row])                   \n\t"
+
+        "daddiu     %[row],    %[row],         0x0c           \n\t"
+        "daddiu     %[prev],   %[prev],        0x0c           \n\t"
+        "daddiu     %[istop],  %[istop],      -0x0c           \n\t"
+        "bgtz       %[istop],  1b                             \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp), [rp1]"=&f"(rp1), [pp1]"=&f"(pp1),
+          [zero]"=&f"(zero), [a]"=&f"(a),[b]"=&f"(b), [c]"=&f"(c),
+          [d]"=&f"(d), [pa]"=&f"(pa), [pb]"=&f"(pb), [pc]"=&f"(pc),
+          [tmp0]"=&r"(tmp0), [ftmp0]"=&f"(ftmp[0]), [ftmp1]"=&f"(ftmp[1]),
+          [ftmp2]"=&f"(ftmp[2]), [eight]"=&f"(eight), [sixteen]"=&f"(sixteen),
+          [twenty_four]"=&f"(twenty_four), [forty_eight]"=&f"(forty_eight)
+        : [row]"r"(row), [prev]"r"(prev), [istop]"r"(istop)
+        : "memory"
+   );
+}
+
+void png_read_filter_row_paeth4_mmi(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev)
+{
+   /* Paeth tries to predict pixel d using the pixel to the left of it, a,
+    * and two pixels from the previous row, b and c:
+    *   prev: c b
+    *   row:  a d
+    * The Paeth function predicts d to be whichever of a, b, or c is nearest to
+    * p=a+b-c.
+    *
+    * The first pixel has no left context, and so uses an Up filter, p = b.
+    * This works naturally with our main loop's p = a+b-c if we force a and c
+    * to zero.
+    * Here we zero b and d, which become c and a respectively at the start of
+    * the loop.
+    */
+   int istop = row_info->rowbytes;
+   double rp, pp, zero;
+   double a, b, c, d, pa, pb, pc;
+   double ftmp[2];
+
+   __asm__ volatile (
+        "xor        %[a],      %[a],           %[a]     \n\t"
+        "xor        %[c],      %[c],           %[c]     \n\t"
+        "xor        %[zero],   %[zero],        %[zero]  \n\t"
+
+        "1:                                             \n\t"
+        "lwc1       %[rp],     0x00(%[row])             \n\t"
+        "lwc1       %[pp],     0x00(%[prev])            \n\t"
+        "punpcklbh  %[b],      %[pp],          %[zero]  \n\t"
+        "punpcklbh  %[d],      %[rp],          %[zero]  \n\t"
+
+        "packushb   %[ftmp0],  %[c],           %[c]     \n\t"
+        "packushb   %[ftmp1],  %[a],           %[a]     \n\t"
+        "pasubub    %[pa],     %[pp],          %[ftmp0] \n\t"
+        "pasubub    %[pb],     %[ftmp1],       %[ftmp0] \n\t"
+        "psubh      %[ftmp0],  %[b],           %[c]     \n\t"
+        "psubh      %[ftmp1],  %[a],           %[c]     \n\t"
+        "paddh      %[pc],     %[ftmp0],       %[ftmp1] \n\t"
+        "pcmpgth    %[ftmp0],  %[zero],        %[pc]    \n\t"
+        "xor        %[pc],     %[pc],          %[ftmp0] \n\t"
+        "psubh      %[pc],     %[pc],          %[ftmp0] \n\t"
+
+        "punpcklbh  %[pa],     %[pa],           %[zero] \n\t"
+        "punpcklbh  %[pb],     %[pb],           %[zero] \n\t"
+
+        "pcmpgth    %[ftmp0],  %[pa],          %[pb]    \n\t"
+        "and        %[ftmp1],  %[b],           %[ftmp0] \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]     \n\t"
+        "or         %[a],      %[a],           %[ftmp1] \n\t"
+        "pminsh     %[pa],     %[pa],          %[pb]    \n\t"
+
+        "pcmpgth    %[ftmp0],  %[pa],          %[pc]    \n\t"
+        "and        %[ftmp1],  %[c],           %[ftmp0] \n\t"
+        "pandn      %[a],      %[ftmp0],       %[a]     \n\t"
+        "or         %[a],      %[a],           %[ftmp1] \n\t"
+        "paddb      %[a],      %[a],           %[d]     \n\t"
+        "packushb   %[d],      %[a],           %[a]     \n\t"
+        "swc1       %[d],      0x00(%[row])             \n\t"
+        "punpcklbh  %[c],      %[pp],          %[zero]  \n\t"
+        "daddiu     %[row],    %[row],         0x04     \n\t"
+        "daddiu     %[prev],   %[prev],        0x04     \n\t"
+        "daddiu     %[istop],  %[istop],      -0x04     \n\t"
+        "bgtz       %[istop],  1b                       \n\t"
+        : [rp]"=&f"(rp), [pp]"=&f"(pp), [zero]"=&f"(zero),
+          [a]"=&f"(a), [b]"=&f"(b), [c]"=&f"(c), [d]"=&f"(d),
+          [pa]"=&f"(pa), [pb]"=&f"(pb), [pc]"=&f"(pc),
+          [ftmp0]"=&f"(ftmp[0]), [ftmp1]"=&f"(ftmp[1])
+        : [row]"r"(row), [prev]"r"(prev), [istop]"r"(istop)
+        : "memory"
+   );
+}
+
+#endif /* PNG_MIPS_MMI_IMPLEMENTATION > 0 */
+#endif /* READ */
diff --git a/mips/filter_msa_intrinsics.c b/mips/filter_msa_intrinsics.c
index a579179..1b734f4 100644
--- a/mips/filter_msa_intrinsics.c
+++ b/mips/filter_msa_intrinsics.c
@@ -1,9 +1,9 @@
 
 /* filter_msa_intrinsics.c - MSA optimised filter functions
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 2016 Glenn Randers-Pehrson
- * Written by Mandar Sahastrabuddhe, August 2016.
+ * Written by Mandar Sahastrabuddhe, August 2016
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -11,7 +11,6 @@
  */
 
 #include <stdio.h>
-#include <stdint.h>
 #include "../pngpriv.h"
 
 #ifdef PNG_READ_SUPPORTED
@@ -20,6 +19,7 @@
 #if PNG_MIPS_MSA_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
 
 #include <msa.h>
+#include <stdint.h>
 
 /* libpng row pointers are not necessarily aligned to any particular boundary,
  * however this code will only work with appropriate alignment. mips/mips_init.c
@@ -379,8 +379,8 @@
       LD_UB4(pp, 16, src4, src5, src6, src7);
       pp += 64;
 
-	  ADD4(src0, src4, src1, src5, src2, src6, src3, src7,
-	       src0, src1, src2, src3);
+      ADD4(src0, src4, src1, src5, src2, src6, src3, src7,
+           src0, src1, src2, src3);
 
       ST_UB4(src0, src1, src2, src3, rp, 16);
       rp += 64;
@@ -400,7 +400,7 @@
             LD_UB4(pp, 16, src4, src5, src6, src7);
 
             ADD4(src0, src4, src1, src5, src2, src6, src3, src7,
-	             src0, src1, src2, src3);
+                 src0, src1, src2, src3);
 
             ST_UB4(src0, src1, src2, src3, rp, 16);
             rp += 64;
@@ -425,7 +425,7 @@
             LD_UB2(rp, 16, src0, src1);
             LD_UB2(pp, 16, src4, src5);
 
-			ADD2(src0, src4, src1, src5, src0, src1);
+            ADD2(src0, src4, src1, src5, src0, src1);
 
             ST_UB2(src0, src1, rp, 16);
             rp += 32;
diff --git a/mips/mips_init.c b/mips/mips_init.c
index 8dd283d..5c6fa1d 100644
--- a/mips/mips_init.c
+++ b/mips/mips_init.c
@@ -1,9 +1,10 @@
 
 /* mips_init.c - MSA optimised filter functions
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 2016 Glenn Randers-Pehrson
- * Written by Mandar Sahastrabuddhe, 2016.
+ * Written by Mandar Sahastrabuddhe, 2016
+ * Updated by guxiwei, 2023
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -20,8 +21,9 @@
 
 #ifdef PNG_READ_SUPPORTED
 
-#if PNG_MIPS_MSA_OPT > 0
-#ifdef PNG_MIPS_MSA_CHECK_SUPPORTED /* Do run-time checks */
+#if PNG_MIPS_MSA_IMPLEMENTATION == 1 || PNG_MIPS_MMI_IMPLEMENTATION > 0
+
+#ifdef PNG_MIPS_MSA_CHECK_SUPPORTED /* Do MIPS MSA run-time checks */
 /* WARNING: it is strongly recommended that you do not build libpng with
  * run-time checks for CPU features if at all possible.  In the case of the MIPS
  * MSA instructions there is no processor-specific way of detecting the
@@ -51,13 +53,83 @@
 #endif /* PNG_MIPS_MSA_FILE */
 #endif /* PNG_MIPS_MSA_CHECK_SUPPORTED */
 
+#ifdef PNG_MIPS_MMI_CHECK_SUPPORTED /* Do MIPS MMI run-times checks */
+#ifndef PNG_MIPS_MMI_FILE
+#  ifdef __linux__
+#     define PNG_MIPS_MMI_FILE "contrib/mips-mmi/linux.c"
+#  endif
+#endif
+
+#ifdef PNG_MIPS_MMI_FILE
+
+#include <signal.h> /* for sig_atomic_t */
+static int png_have_mmi();
+#include PNG_MIPS_MMI_FILE
+
+#else  /* PNG_MIPS_MMI_FILE */
+#  error "PNG_MIPS_MMI_FILE undefined: no support for run-time MIPS MMI checks"
+#endif /* PNG_MIPS_MMI_FILE */
+#endif /* PNG_MIPS_MMI_CHECK_SUPPORTED*/
+
 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
 #  error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
 #endif
 
+/* MIPS supports two optimizations: MMI and MSA. The appropriate
+ * optimization is chosen at runtime
+ */
 void
-png_init_filter_functions_msa(png_structp pp, unsigned int bpp)
+png_init_filter_functions_mips(png_structp pp, unsigned int bpp)
 {
+#if PNG_MIPS_MMI_IMPLEMENTATION  > 0
+#ifdef PNG_MIPS_MMI_API_SUPPORTED
+   switch ((pp->options >> PNG_MIPS_MMI) & 3)
+   {
+      case PNG_OPTION_UNSET:
+#endif /* PNG_MIPS_MMI_API_SUPPORTED */
+#ifdef PNG_MIPS_MMI_CHECK_SUPPORTED
+         {
+            static volatile sig_atomic_t no_mmi = -1; /* not checked */
+
+            if (no_mmi < 0)
+               no_mmi = !png_have_mmi();
+
+            if (no_mmi)
+              goto MIPS_MSA_INIT;
+         }
+#ifdef PNG_MIPS_MMI_API_SUPPORTED
+         break;
+#endif
+#endif /* PNG_MIPS_MMI_CHECK_SUPPORTED */
+
+#ifdef PNG_MIPS_MMI_API_SUPPORTED
+      default: /* OFF or INVALID */
+         goto MIPS_MSA_INIT;
+
+      case PNG_OPTION_ON:
+         /* Option turned on */
+         break;
+   }
+#endif
+   pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up_mmi;
+   if (bpp == 3)
+   {
+      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub3_mmi;
+      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg3_mmi;
+      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+         png_read_filter_row_paeth3_mmi;
+   }
+   else if (bpp == 4)
+   {
+      pp->read_filter[PNG_FILTER_VALUE_SUB-1] = png_read_filter_row_sub4_mmi;
+      pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_mmi;
+      pp->read_filter[PNG_FILTER_VALUE_PAETH-1] =
+          png_read_filter_row_paeth4_mmi;
+   }
+#endif /* PNG_MIPS_MMI_IMPLEMENTATION > 0 */
+
+MIPS_MSA_INIT:
+#if PNG_MIPS_MSA_IMPLEMENTATION == 1
    /* The switch statement is compiled in for MIPS_MSA_API, the call to
     * png_have_msa is compiled in for MIPS_MSA_CHECK. If both are defined
     * the check is only performed if the API has not set the MSA option on
@@ -125,6 +197,8 @@
       pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg4_msa;
       pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = png_read_filter_row_paeth4_msa;
    }
+#endif /* PNG_MIPS_MSA_IMPLEMENTATION == 1 */
+   return;
 }
-#endif /* PNG_MIPS_MSA_OPT > 0 */
+#endif /* PNG_MIPS_MSA_IMPLEMENTATION == 1 || PNG_MIPS_MMI_IMPLEMENTATION > 0 */
 #endif /* READ */
diff --git a/missing b/missing
index 625aeb1..1fe1611 100755
--- a/missing
+++ b/missing
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 1996-2018 Free Software Foundation, Inc.
+# Copyright (C) 1996-2021 Free Software Foundation, Inc.
 # Originally written by Fran,cois Pinard <pinard@iro.umontreal.ca>, 1996.
 
 # This program is free software; you can redistribute it and/or modify
diff --git a/png.5 b/png.5
index c2da95c..1737ba5 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "April 14, 2019"
+.TH PNG 5 "January 29, 2024"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 
@@ -18,7 +18,7 @@
 matching on heterogeneous platforms.
 
 .SH "SEE ALSO"
-.BR "libpng"(3), " libpngpf"(3), " zlib"(3), " deflate"(5), " " and " zlib"(5)
+.BR "libpng"(3), " zlib"(3), " deflate"(5), " " and " zlib"(5)
 .LP
 PNG Specification (Second Edition), November 2003:
 .IP
@@ -43,7 +43,7 @@
 https://www.w3.org/TR/REC-png-961001
 
 .SH AUTHORS
-This man page: Cosmin Truta, Glenn Randers-Pehrson
+This man page: Glenn Randers-Pehrson, Cosmin Truta
 .LP
 Portable Network Graphics (PNG) Specification (Second Edition)
 Information technology - Computer graphics and image processing -
@@ -51,34 +51,9 @@
 ISO/IEC 15948:2003 (E) (November 10, 2003): David Duce and others.
 .LP
 Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999):
-Glenn Randers-Pehrson and others (png-list).
+Glenn Randers-Pehrson and others.
 .LP
 Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
-Thomas Boutell and others (png-list).
+Thomas Boutell and others.
 
-.SH COPYRIGHT
-.LP
-This man page is
-.br
-Copyright (c) 2018-2019 Cosmin Truta.
-.br
-Copyright (c) 1998-2006 Glenn Randers-Pehrson.
-.br
-See png.h for conditions of use and distribution.
-.LP
-The PNG Specification (Second Edition) is
-.br
-Copyright (c) 2003 W3C. (MIT, ERCIM, Keio), All Rights Reserved.
-.LP
-The PNG-1.2 Specification is
-.br
-Copyright (c) 1999 Glenn Randers-Pehrson.
-.br
-See the specification for conditions of use and distribution.
-.LP
-The PNG-1.0 Specification is
-.br
-Copyright (c) 1996 Massachusetts Institute of Technology.
-.br
-See the specification for conditions of use and distribution.
 .\" end of man page
diff --git a/png.c b/png.c
index e92008d..997b8d4 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -14,27 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_38_git Your_png_h_is_not_version_1_6_38_git;
-
-#ifdef __GNUC__
-/* The version tests may need to be added to, but the problem warning has
- * consistently been fixed in GCC versions which obtain wide-spread release.
- * The problem is that many versions of GCC rearrange comparison expressions in
- * the optimizer in such a way that the results of the comparison will change
- * if signed integer overflow occurs.  Such comparisons are not permitted in
- * ANSI C90, however GCC isn't clever enough to work out that that do not occur
- * below in png_ascii_from_fp and png_muldiv, so it produces a warning with
- * -Wextra.  Unfortunately this is highly dependent on the optimizer and the
- * machine architecture so the warning comes and goes unpredictably and is
- * impossible to "fix", even were that a good idea.
- */
-#if __GNUC__ == 7 && __GNUC_MINOR__ == 1
-#define GCC_STRICT_OVERFLOW 1
-#endif /* GNU 7.1.x */
-#endif /* GNU */
-#ifndef GCC_STRICT_OVERFLOW
-#define GCC_STRICT_OVERFLOW 0
-#endif
+typedef png_libpng_version_1_6_43_git Your_png_h_is_not_version_1_6_43_git;
 
 /* Tells libpng that we have already handled the first "num_bytes" bytes
  * of the PNG file signature.  If the PNG data is embedded into another
@@ -73,21 +53,21 @@
 int PNGAPI
 png_sig_cmp(png_const_bytep sig, size_t start, size_t num_to_check)
 {
-   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
+   static const png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
 
    if (num_to_check > 8)
       num_to_check = 8;
 
    else if (num_to_check < 1)
-      return (-1);
+      return -1;
 
    if (start > 7)
-      return (-1);
+      return -1;
 
    if (start + num_to_check > 8)
       num_to_check = 8 - start;
 
-   return ((int)(memcmp(&sig[start], &png_signature[start], num_to_check)));
+   return memcmp(&sig[start], &png_signature[start], num_to_check);
 }
 
 #endif /* READ */
@@ -447,7 +427,6 @@
    memset(info_ptr, 0, (sizeof *info_ptr));
 }
 
-/* The following API is not called internally */
 void PNGAPI
 png_data_freer(png_const_structrp png_ptr, png_inforp info_ptr,
     int freer, png_uint_32 mask)
@@ -686,9 +665,9 @@
 png_get_io_ptr(png_const_structrp png_ptr)
 {
    if (png_ptr == NULL)
-      return (NULL);
+      return NULL;
 
-   return (png_ptr->io_ptr);
+   return png_ptr->io_ptr;
 }
 
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
@@ -720,7 +699,7 @@
  *
  * Where UNSIGNED_MAX is the appropriate maximum unsigned value, so when the
  * negative integral value is added the result will be an unsigned value
- * correspnding to the 2's complement representation.
+ * corresponding to the 2's complement representation.
  */
 void PNGAPI
 png_save_int_32(png_bytep buf, png_int_32 i)
@@ -752,7 +731,7 @@
 
    {
       size_t pos = 0;
-      char number_buf[5]; /* enough for a four-digit year */
+      char number_buf[5] = {0, 0, 0, 0, 0}; /* enough for a four-digit year */
 
 #     define APPEND_STRING(string) pos = png_safecat(out, 29, pos, (string))
 #     define APPEND_NUMBER(format, value)\
@@ -815,8 +794,8 @@
    return PNG_STRING_COPYRIGHT
 #else
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.38.git" PNG_STRING_NEWLINE \
-      "Copyright (c) 2018-2019 Cosmin Truta" PNG_STRING_NEWLINE \
+      "libpng version 1.6.43.git" PNG_STRING_NEWLINE \
+      "Copyright (c) 2018-2024 Cosmin Truta" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \
       PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
@@ -977,7 +956,7 @@
       return Z_STREAM_ERROR;
 
    /* WARNING: this resets the window bits to the maximum! */
-   return (inflateReset(&png_ptr->zstream));
+   return inflateReset(&png_ptr->zstream);
 }
 #endif /* READ */
 
@@ -986,7 +965,7 @@
 png_access_version_number(void)
 {
    /* Version of *.c files used when building libpng */
-   return((png_uint_32)PNG_LIBPNG_VER);
+   return (png_uint_32)PNG_LIBPNG_VER;
 }
 
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
@@ -1843,12 +1822,12 @@
 #  ifdef PNG_WARNINGS_SUPPORTED
    else
       {
-         char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114*/
+         char number[PNG_NUMBER_BUFFER_SIZE]; /* +24 = 114 */
 
          pos = png_safecat(message, (sizeof message), pos,
              png_format_number(number, number+(sizeof number),
              PNG_NUMBER_FORMAT_x, value));
-         pos = png_safecat(message, (sizeof message), pos, "h: "); /*+2 = 116*/
+         pos = png_safecat(message, (sizeof message), pos, "h: "); /* +2 = 116 */
       }
 #  endif
    /* The 'reason' is an arbitrary message, allow +79 maximum 195 */
@@ -2532,17 +2511,6 @@
 
 #endif /* COLORSPACE */
 
-#ifdef __GNUC__
-/* This exists solely to work round a warning from GNU C. */
-static int /* PRIVATE */
-png_gt(size_t a, size_t b)
-{
-   return a > b;
-}
-#else
-#   define png_gt(a,b) ((a) > (b))
-#endif
-
 void /* PRIVATE */
 png_check_IHDR(png_const_structrp png_ptr,
     png_uint_32 width, png_uint_32 height, int bit_depth,
@@ -2564,8 +2532,16 @@
       error = 1;
    }
 
-   if (png_gt(((width + 7) & (~7U)),
-       ((PNG_SIZE_MAX
+   /* The bit mask on the first line below must be at least as big as a
+    * png_uint_32.  "~7U" is not adequate on 16-bit systems because it will
+    * be an unsigned 16-bit value.  Casting to (png_alloc_size_t) makes the
+    * type of the result at least as bit (in bits) as the RHS of the > operator
+    * which also avoids a common warning on 64-bit systems that the comparison
+    * of (png_uint_32) against the constant value on the RHS will always be
+    * false.
+    */
+   if (((width + 7) & ~(png_alloc_size_t)7) >
+       (((PNG_SIZE_MAX
            - 48        /* big_row_buf hack */
            - 1)        /* filter byte */
            / 8)        /* 8-byte RGBA pixels */
@@ -2710,7 +2686,7 @@
 
 int /* PRIVATE */
 png_check_fp_number(png_const_charp string, size_t size, int *statep,
-    png_size_tp whereami)
+    size_t *whereami)
 {
    int state = *statep;
    size_t i = *whereami;
@@ -2891,14 +2867,6 @@
 /* Function to format a floating point value in ASCII with a given
  * precision.
  */
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic push
-/* The problem arises below with exp_b10, which can never overflow because it
- * comes, originally, from frexp and is therefore limited to a range which is
- * typically +/-710 (log2(DBL_MAX)/log2(DBL_MIN)).
- */
-#pragma GCC diagnostic warning "-Wstrict-overflow=2"
-#endif /* GCC_STRICT_OVERFLOW */
 void /* PRIVATE */
 png_ascii_from_fp(png_const_structrp png_ptr, png_charp ascii, size_t size,
     double fp, unsigned int precision)
@@ -3220,10 +3188,6 @@
    /* Here on buffer too small. */
    png_error(png_ptr, "ASCII conversion buffer too small");
 }
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic pop
-#endif /* GCC_STRICT_OVERFLOW */
-
 #  endif /* FLOATING_POINT */
 
 #  ifdef PNG_FIXED_POINT_SUPPORTED
@@ -3251,7 +3215,7 @@
       if (num <= 0x80000000) /* else overflowed */
       {
          unsigned int ndigits = 0, first = 16 /* flag value */;
-         char digits[10];
+         char digits[10] = {0};
 
          while (num)
          {
@@ -3336,15 +3300,6 @@
  * the nearest .00001).  Overflow and divide by zero are signalled in
  * the result, a boolean - true on success, false on overflow.
  */
-#if GCC_STRICT_OVERFLOW /* from above */
-/* It is not obvious which comparison below gets optimized in such a way that
- * signed overflow would change the result; looking through the code does not
- * reveal any tests which have the form GCC complains about, so presumably the
- * optimizer is moving an add or subtract into the 'if' somewhere.
- */
-#pragma GCC diagnostic push
-#pragma GCC diagnostic warning "-Wstrict-overflow=2"
-#endif /* GCC_STRICT_OVERFLOW */
 int
 png_muldiv(png_fixed_point_p res, png_fixed_point a, png_int_32 times,
     png_int_32 divisor)
@@ -3459,9 +3414,6 @@
 
    return 0;
 }
-#if GCC_STRICT_OVERFLOW
-#pragma GCC diagnostic pop
-#endif /* GCC_STRICT_OVERFLOW */
 #endif /* READ_GAMMA || INCH_CONVERSIONS */
 
 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
diff --git a/png.h b/png.h
index 57b9399..013f309 100644
--- a/png.h
+++ b/png.h
@@ -1,9 +1,9 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.38.git
+ * libpng version 1.6.43.git
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -15,7 +15,7 @@
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
  *   libpng versions 0.97, January 1998, through 1.6.35, July 2018:
  *     Glenn Randers-Pehrson
- *   libpng versions 1.6.36, December 2018, through 1.6.37, April 2019:
+ *   libpng versions 1.6.36, December 2018, through 1.6.42, January 2024:
  *     Cosmin Truta
  *   See also "Contributing Authors", below.
  */
@@ -27,8 +27,8 @@
  * PNG Reference Library License version 2
  * ---------------------------------------
  *
- *  * Copyright (c) 1995-2019 The PNG Reference Library Authors.
- *  * Copyright (c) 2018-2019 Cosmin Truta.
+ *  * Copyright (c) 1995-2024 The PNG Reference Library Authors.
+ *  * Copyright (c) 2018-2024 Cosmin Truta.
  *  * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
  *  * Copyright (c) 1996-1997 Andreas Dilger.
  *  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -239,7 +239,7 @@
  *    ...
  *    1.5.30                  15    10530  15.so.15.30[.0]
  *    ...
- *    1.6.37                  16    10637  16.so.16.37[.0]
+ *    1.6.42                  16    10642  16.so.16.42[.0]
  *
  *    Henceforth the source version will match the shared-library major and
  *    minor numbers; the shared-library major version number will be used for
@@ -255,9 +255,6 @@
  *    to the info_ptr or png_ptr members through png.h, and the compiled
  *    application is loaded with a different version of the library.
  *
- *    DLLNUM will change each time there are forward or backward changes
- *    in binary compatibility (e.g., when a new feature is added).
- *
  * See libpng.txt or libpng.3 for more information.  The PNG specification
  * is available as a W3C Recommendation and as an ISO/IEC Standard; see
  * <https://www.w3.org/TR/2003/REC-PNG-20031110/>
@@ -278,16 +275,18 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.38.git"
-#define PNG_HEADER_VERSION_STRING " libpng version 1.6.38.git\n"
+#define PNG_LIBPNG_VER_STRING "1.6.43.git"
+#define PNG_HEADER_VERSION_STRING " libpng version " PNG_LIBPNG_VER_STRING "\n"
 
-#define PNG_LIBPNG_VER_SONUM   16
-#define PNG_LIBPNG_VER_DLLNUM  16
+/* The versions of shared library builds should stay in sync, going forward */
+#define PNG_LIBPNG_VER_SHAREDLIB 16
+#define PNG_LIBPNG_VER_SONUM     PNG_LIBPNG_VER_SHAREDLIB /* [Deprecated] */
+#define PNG_LIBPNG_VER_DLLNUM    PNG_LIBPNG_VER_SHAREDLIB /* [Deprecated] */
 
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   6
-#define PNG_LIBPNG_VER_RELEASE 38
+#define PNG_LIBPNG_VER_RELEASE 43
 
 /* This should be zero for a public release, or non-zero for a
  * development version.  [Deprecated]
@@ -295,9 +294,9 @@
 #define PNG_LIBPNG_VER_BUILD  1
 
 /* Release Status */
-#define PNG_LIBPNG_BUILD_ALPHA    1
+#define PNG_LIBPNG_BUILD_ALPHA    1 /* [Deprecated] */
 #define PNG_LIBPNG_BUILD_BETA     2
-#define PNG_LIBPNG_BUILD_RC       3
+#define PNG_LIBPNG_BUILD_RC       3 /* [Deprecated] */
 #define PNG_LIBPNG_BUILD_STABLE   4
 #define PNG_LIBPNG_BUILD_RELEASE_STATUS_MASK 7
 
@@ -318,7 +317,7 @@
  * From version 1.0.1 it is:
  * XXYYZZ, where XX=major, YY=minor, ZZ=release
  */
-#define PNG_LIBPNG_VER 10638 /* 1.6.38.git */
+#define PNG_LIBPNG_VER 10643 /* 1.6.43.git */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
@@ -428,7 +427,7 @@
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef char* png_libpng_version_1_6_38_git;
+typedef char* png_libpng_version_1_6_43_git;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -849,7 +848,7 @@
 #define PNG_TRANSFORM_GRAY_TO_RGB   0x2000      /* read only */
 /* Added to libpng-1.5.4 */
 #define PNG_TRANSFORM_EXPAND_16     0x4000      /* read only */
-#if INT_MAX >= 0x8000 /* else this might break */
+#if ~0U > 0xffffU /* or else this might break on a 16-bit machine */
 #define PNG_TRANSFORM_SCALE_16      0x8000      /* read only */
 #endif
 
@@ -908,15 +907,15 @@
 /* Check sig[start] through sig[start + num_to_check - 1] to see if it's a
  * PNG file.  Returns zero if the supplied bytes match the 8-byte PNG
  * signature, and non-zero otherwise.  Having num_to_check == 0 or
- * start > 7 will always fail (ie return non-zero).
+ * start > 7 will always fail (i.e. return non-zero).
  */
 PNG_EXPORT(3, int, png_sig_cmp, (png_const_bytep sig, size_t start,
     size_t num_to_check));
 
 /* Simple signature checking function.  This is the same as calling
- * png_check_sig(sig, n) := !png_sig_cmp(sig, 0, n).
+ * png_check_sig(sig, n) := (png_sig_cmp(sig, 0, n) == 0).
  */
-#define png_check_sig(sig, n) !png_sig_cmp((sig), 0, (n))
+#define png_check_sig(sig, n) (png_sig_cmp((sig), 0, (n)) == 0) /* DEPRECATED */
 
 /* Allocate and initialize png_ptr struct for reading, and any other memory. */
 PNG_EXPORTA(4, png_structp, png_create_read_struct,
@@ -1446,7 +1445,7 @@
  * mainly useful for testing, as the defaults should work with most users.
  * Those users who are tight on memory or want faster performance at the
  * expense of compression can modify them.  See the compression library
- * header file (zlib.h) for an explination of the compression functions.
+ * header file (zlib.h) for an explanation of the compression functions.
  */
 
 /* Set the filtering method(s) used by libpng.  Currently, the only valid
@@ -1501,7 +1500,7 @@
  * 0 - 9, corresponding directly to the zlib compression levels 0 - 9
  * (0 - no compression, 9 - "maximal" compression).  Note that tests have
  * shown that zlib compression levels 3-6 usually perform as well as level 9
- * for PNG images, and do considerably fewer caclulations.  In the future,
+ * for PNG images, and do considerably fewer calculations.  In the future,
  * these values may not correspond directly to the zlib compression levels.
  */
 #ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
@@ -1730,12 +1729,9 @@
 PNG_EXPORT(98, void, png_free_data, (png_const_structrp png_ptr,
     png_inforp info_ptr, png_uint_32 free_me, int num));
 
-/* Reassign responsibility for freeing existing data, whether allocated
+/* Reassign the responsibility for freeing existing data, whether allocated
  * by libpng or by the application; this works on the png_info structure passed
- * in, it does not change the state for other png_info structures.
- *
- * It is unlikely that this function works correctly as of 1.6.0 and using it
- * may result either in memory leaks or double free of allocated data.
+ * in, without changing the state for other png_info structures.
  */
 PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr,
     png_inforp info_ptr, int freer, png_uint_32 mask));
@@ -3207,11 +3203,18 @@
 #ifdef PNG_MIPS_MSA_API_SUPPORTED
 #  define PNG_MIPS_MSA   6 /* HARDWARE: MIPS Msa SIMD instructions supported */
 #endif
-#define PNG_IGNORE_ADLER32 8
-#ifdef PNG_POWERPC_VSX_API_SUPPORTED
-#  define PNG_POWERPC_VSX   10 /* HARDWARE: PowerPC VSX SIMD instructions supported */
+#ifdef PNG_DISABLE_ADLER32_CHECK_SUPPORTED
+#  define PNG_IGNORE_ADLER32 8 /* SOFTWARE: disable Adler32 check on IDAT */
 #endif
-#define PNG_OPTION_NEXT  12 /* Next option - numbers must be even */
+#ifdef PNG_POWERPC_VSX_API_SUPPORTED
+#  define PNG_POWERPC_VSX   10 /* HARDWARE: PowerPC VSX SIMD instructions
+                                * supported */
+#endif
+#ifdef PNG_MIPS_MMI_API_SUPPORTED
+#  define PNG_MIPS_MMI   12 /* HARDWARE: MIPS MMI SIMD instructions supported */
+#endif
+
+#define PNG_OPTION_NEXT  14 /* Next option - numbers must be even */
 
 /* Return values: NOTE: there are four values and 'off' is *not* zero */
 #define PNG_OPTION_UNSET   0 /* Unset - defaults to off */
diff --git a/pngconf.h b/pngconf.h
index 8c56d40..f58d206 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,9 +1,9 @@
 
 /* pngconf.h - machine-configurable file for libpng
  *
- * libpng version 1.6.38.git
+ * libpng version 1.6.43.git
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2016,2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -180,8 +180,8 @@
  * compiler-specific macros to the values required to change the calling
  * conventions of the various functions.
  */
-#if defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
-    defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
+#if defined(_WIN32) || defined(__WIN32__) || defined(__NT__) || \
+    defined(__CYGWIN__)
   /* Windows system (DOS doesn't support DLLs).  Includes builds under Cygwin or
    * MinGW on any architecture currently supported by Windows.  Also includes
    * Watcom builds but these need special treatment because they are not
diff --git a/pngerror.c b/pngerror.c
index ec3a709..29ebda7 100644
--- a/pngerror.c
+++ b/pngerror.c
@@ -1,7 +1,7 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -255,7 +255,7 @@
 png_warning_parameter_unsigned(png_warning_parameters p, int number, int format,
     png_alloc_size_t value)
 {
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
+   char buffer[PNG_NUMBER_BUFFER_SIZE] = {0};
    png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value));
 }
 
@@ -265,7 +265,7 @@
 {
    png_alloc_size_t u;
    png_charp str;
-   char buffer[PNG_NUMBER_BUFFER_SIZE];
+   char buffer[PNG_NUMBER_BUFFER_SIZE] = {0};
 
    /* Avoid overflow by doing the negate in a png_alloc_size_t: */
    u = (png_alloc_size_t)value;
@@ -858,7 +858,7 @@
    if (png_ptr == NULL)
       return NULL;
 
-   return ((png_voidp)png_ptr->error_ptr);
+   return (png_voidp)png_ptr->error_ptr;
 }
 
 
@@ -933,31 +933,25 @@
 #endif
 
 int /* PRIVATE */
-png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg)
+png_safe_execute(png_imagep image, int (*function)(png_voidp), png_voidp arg)
 {
-   volatile png_imagep image = image_in;
-   volatile int result;
-   volatile png_voidp saved_error_buf;
+   png_voidp saved_error_buf = image->opaque->error_buf;
    jmp_buf safe_jmpbuf;
+   int result;
 
-   /* Safely execute function(arg) with png_error returning to this function. */
-   saved_error_buf = image->opaque->error_buf;
-   result = setjmp(safe_jmpbuf) == 0;
-
-   if (result != 0)
+   /* Safely execute function(arg), with png_error returning back here. */
+   if (setjmp(safe_jmpbuf) == 0)
    {
-
       image->opaque->error_buf = safe_jmpbuf;
       result = function(arg);
+      image->opaque->error_buf = saved_error_buf;
+      return result;
    }
 
+   /* On png_error, return via longjmp, pop the jmpbuf, and free the image. */
    image->opaque->error_buf = saved_error_buf;
-
-   /* And do the cleanup prior to any failure return. */
-   if (result == 0)
-      png_image_free(image);
-
-   return result;
+   png_image_free(image);
+   return 0;
 }
 #endif /* SIMPLIFIED READ || SIMPLIFIED_WRITE */
 #endif /* READ || WRITE */
diff --git a/pngget.c b/pngget.c
index 5abf1ef..1084b26 100644
--- a/pngget.c
+++ b/pngget.c
@@ -1,7 +1,7 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -21,18 +21,29 @@
     png_uint_32 flag)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->valid & flag);
+   {
+#ifdef PNG_READ_tRNS_SUPPORTED
+      /* png_handle_PLTE() may have canceled a valid tRNS chunk but left the
+       * 'valid' flag for the detection of duplicate chunks. Do not report a
+       * valid tRNS chunk in this case.
+       */
+      if (flag == PNG_INFO_tRNS && png_ptr->num_trans == 0)
+         return 0;
+#endif
 
-   return(0);
+      return info_ptr->valid & flag;
+   }
+
+   return 0;
 }
 
 size_t PNGAPI
 png_get_rowbytes(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->rowbytes);
+      return info_ptr->rowbytes;
 
-   return(0);
+   return 0;
 }
 
 #ifdef PNG_INFO_IMAGE_SUPPORTED
@@ -40,9 +51,9 @@
 png_get_rows(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->row_pointers);
+      return info_ptr->row_pointers;
 
-   return(0);
+   return 0;
 }
 #endif
 
@@ -54,7 +65,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->width;
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
@@ -63,7 +74,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->height;
 
-   return (0);
+   return 0;
 }
 
 png_byte PNGAPI
@@ -72,7 +83,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->bit_depth;
 
-   return (0);
+   return 0;
 }
 
 png_byte PNGAPI
@@ -81,7 +92,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->color_type;
 
-   return (0);
+   return 0;
 }
 
 png_byte PNGAPI
@@ -90,7 +101,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->filter_type;
 
-   return (0);
+   return 0;
 }
 
 png_byte PNGAPI
@@ -99,7 +110,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->interlace_type;
 
-   return (0);
+   return 0;
 }
 
 png_byte PNGAPI
@@ -108,7 +119,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return info_ptr->compression_type;
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
@@ -116,21 +127,20 @@
    info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
+   png_debug(1, "in png_get_x_pixels_per_meter");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0)
-      {
-         png_debug1(1, "in %s retrieval function",
-             "png_get_x_pixels_per_meter");
-
-         if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
-            return (info_ptr->x_pixels_per_unit);
-      }
+   {
+      if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
+         return info_ptr->x_pixels_per_unit;
+   }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
@@ -138,42 +148,41 @@
     info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
+   png_debug(1, "in png_get_y_pixels_per_meter");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
-      png_debug1(1, "in %s retrieval function",
-          "png_get_y_pixels_per_meter");
-
       if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
-         return (info_ptr->y_pixels_per_unit);
+         return info_ptr->y_pixels_per_unit;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
 png_get_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
+   png_debug(1, "in png_get_pixels_per_meter");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");
-
       if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER &&
           info_ptr->x_pixels_per_unit == info_ptr->y_pixels_per_unit)
-         return (info_ptr->x_pixels_per_unit);
+         return info_ptr->x_pixels_per_unit;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 #ifdef PNG_FLOATING_POINT_SUPPORTED
@@ -182,21 +191,21 @@
    info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
+   png_debug(1, "in png_get_pixel_aspect_ratio");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
-
       if (info_ptr->x_pixels_per_unit != 0)
-         return ((float)((float)info_ptr->y_pixels_per_unit
-             /(float)info_ptr->x_pixels_per_unit));
+         return (float)info_ptr->y_pixels_per_unit
+              / (float)info_ptr->x_pixels_per_unit;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return ((float)0.0);
+   return (float)0.0;
 }
 #endif
 
@@ -206,6 +215,8 @@
     png_const_inforp info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
+   png_debug(1, "in png_get_pixel_aspect_ratio_fixed");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0 &&
        info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0 &&
@@ -214,8 +225,6 @@
    {
       png_fixed_point res;
 
-      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio_fixed");
-
       /* The following casts work because a PNG 4 byte integer only has a valid
        * range of 0..2^31-1; otherwise the cast might overflow.
        */
@@ -236,80 +245,80 @@
 png_get_x_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
+   png_debug(1, "in png_get_x_offset_microns");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
-
       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
-         return (info_ptr->x_offset);
+         return info_ptr->x_offset;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 png_int_32 PNGAPI
 png_get_y_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
+   png_debug(1, "in png_get_y_offset_microns");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
-
       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
-         return (info_ptr->y_offset);
+         return info_ptr->y_offset;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 png_int_32 PNGAPI
 png_get_x_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
+   png_debug(1, "in png_get_x_offset_pixels");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
-
       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
-         return (info_ptr->x_offset);
+         return info_ptr->x_offset;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 png_int_32 PNGAPI
 png_get_y_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
+   png_debug(1, "in png_get_y_offset_pixels");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
-
       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
-         return (info_ptr->y_offset);
+         return info_ptr->y_offset;
    }
 #else
    PNG_UNUSED(png_ptr)
    PNG_UNUSED(info_ptr)
 #endif
 
-   return (0);
+   return 0;
 }
 
 #ifdef PNG_INCH_CONVERSIONS_SUPPORTED
@@ -423,11 +432,11 @@
 {
    png_uint_32 retval = 0;
 
+   png_debug1(1, "in %s retrieval function", "pHYs");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "pHYs");
-
       if (res_x != NULL)
       {
          *res_x = info_ptr->x_pixels_per_unit;
@@ -453,7 +462,7 @@
       }
    }
 
-   return (retval);
+   return retval;
 }
 #endif /* pHYs */
 #endif /* INCH_CONVERSIONS */
@@ -467,9 +476,9 @@
 png_get_channels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->channels);
+      return info_ptr->channels;
 
-   return (0);
+   return 0;
 }
 
 #ifdef PNG_READ_SUPPORTED
@@ -477,9 +486,9 @@
 png_get_signature(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
    if (png_ptr != NULL && info_ptr != NULL)
-      return(info_ptr->signature);
+      return info_ptr->signature;
 
-   return (NULL);
+   return NULL;
 }
 #endif
 
@@ -488,17 +497,17 @@
 png_get_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
     png_color_16p *background)
 {
+   png_debug1(1, "in %s retrieval function", "bKGD");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_bKGD) != 0 &&
        background != NULL)
    {
-      png_debug1(1, "in %s retrieval function", "bKGD");
-
       *background = &(info_ptr->background);
-      return (PNG_INFO_bKGD);
+      return PNG_INFO_bKGD;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -513,6 +522,8 @@
     double *white_x, double *white_y, double *red_x, double *red_y,
     double *green_x, double *green_y, double *blue_x, double *blue_y)
 {
+   png_debug1(1, "in %s retrieval function", "cHRM");
+
    /* Quiet API change: this code used to only return the end points if a cHRM
     * chunk was present, but the end points can also come from iCCP or sRGB
     * chunks, so in 1.6.0 the png_get_ APIs return the end points regardless and
@@ -522,8 +533,6 @@
    if (png_ptr != NULL && info_ptr != NULL &&
       (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "cHRM");
-
       if (white_x != NULL)
          *white_x = png_float(png_ptr,
              info_ptr->colorspace.end_points_xy.whitex, "cHRM white X");
@@ -548,10 +557,10 @@
       if (blue_y != NULL)
          *blue_y = png_float(png_ptr, info_ptr->colorspace.end_points_xy.bluey,
              "cHRM blue Y");
-      return (PNG_INFO_cHRM);
+      return PNG_INFO_cHRM;
    }
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
@@ -560,11 +569,11 @@
     double *green_Y, double *green_Z, double *blue_X, double *blue_Y,
     double *blue_Z)
 {
+   png_debug1(1, "in %s retrieval function", "cHRM_XYZ(float)");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "cHRM_XYZ(float)");
-
       if (red_X != NULL)
          *red_X = png_float(png_ptr, info_ptr->colorspace.end_points_XYZ.red_X,
              "cHRM red X");
@@ -592,10 +601,10 @@
       if (blue_Z != NULL)
          *blue_Z = png_float(png_ptr,
              info_ptr->colorspace.end_points_XYZ.blue_Z, "cHRM blue Z");
-      return (PNG_INFO_cHRM);
+      return PNG_INFO_cHRM;
    }
 
-   return (0);
+   return 0;
 }
 #  endif
 
@@ -608,11 +617,11 @@
     png_fixed_point *int_blue_X, png_fixed_point *int_blue_Y,
     png_fixed_point *int_blue_Z)
 {
+   png_debug1(1, "in %s retrieval function", "cHRM_XYZ");
+
    if (png_ptr != NULL && info_ptr != NULL &&
       (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "cHRM_XYZ");
-
       if (int_red_X != NULL)
          *int_red_X = info_ptr->colorspace.end_points_XYZ.red_X;
       if (int_red_Y != NULL)
@@ -631,10 +640,10 @@
          *int_blue_Y = info_ptr->colorspace.end_points_XYZ.blue_Y;
       if (int_blue_Z != NULL)
          *int_blue_Z = info_ptr->colorspace.end_points_XYZ.blue_Z;
-      return (PNG_INFO_cHRM);
+      return PNG_INFO_cHRM;
    }
 
-   return (0);
+   return 0;
 }
 
 png_uint_32 PNGAPI
@@ -664,10 +673,10 @@
          *blue_x = info_ptr->colorspace.end_points_xy.bluex;
       if (blue_y != NULL)
          *blue_y = info_ptr->colorspace.end_points_xy.bluey;
-      return (PNG_INFO_cHRM);
+      return PNG_INFO_cHRM;
    }
 
-   return (0);
+   return 0;
 }
 #  endif
 #endif
@@ -685,10 +694,10 @@
        file_gamma != NULL)
    {
       *file_gamma = info_ptr->colorspace.gamma;
-      return (PNG_INFO_gAMA);
+      return PNG_INFO_gAMA;
    }
 
-   return (0);
+   return 0;
 }
 #  endif
 
@@ -705,10 +714,10 @@
    {
       *file_gamma = png_float(png_ptr, info_ptr->colorspace.gamma,
           "png_get_gAMA");
-      return (PNG_INFO_gAMA);
+      return PNG_INFO_gAMA;
    }
 
-   return (0);
+   return 0;
 }
 #  endif
 #endif
@@ -724,10 +733,10 @@
       (info_ptr->valid & PNG_INFO_sRGB) != 0 && file_srgb_intent != NULL)
    {
       *file_srgb_intent = info_ptr->colorspace.rendering_intent;
-      return (PNG_INFO_sRGB);
+      return PNG_INFO_sRGB;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -751,10 +760,10 @@
        */
       if (compression_type != NULL)
          *compression_type = PNG_COMPRESSION_TYPE_BASE;
-      return (PNG_INFO_iCCP);
+      return PNG_INFO_iCCP;
    }
 
-   return (0);
+   return 0;
 
 }
 #endif
@@ -764,13 +773,15 @@
 png_get_sPLT(png_const_structrp png_ptr, png_inforp info_ptr,
     png_sPLT_tpp spalettes)
 {
+   png_debug1(1, "in %s retrieval function", "sPLT");
+
    if (png_ptr != NULL && info_ptr != NULL && spalettes != NULL)
    {
       *spalettes = info_ptr->splt_palettes;
       return info_ptr->splt_palettes_num;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -796,10 +807,10 @@
    {
       *num_exif = info_ptr->num_exif;
       *exif = info_ptr->exif;
-      return (PNG_INFO_eXIf);
+      return PNG_INFO_eXIf;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -814,10 +825,10 @@
        (info_ptr->valid & PNG_INFO_hIST) != 0 && hist != NULL)
    {
       *hist = info_ptr->hist;
-      return (PNG_INFO_hIST);
+      return PNG_INFO_hIST;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -830,7 +841,7 @@
    png_debug1(1, "in %s retrieval function", "IHDR");
 
    if (png_ptr == NULL || info_ptr == NULL)
-      return (0);
+      return 0;
 
    if (width != NULL)
        *width = info_ptr->width;
@@ -862,7 +873,7 @@
        info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
        info_ptr->compression_type, info_ptr->filter_type);
 
-   return (1);
+   return 1;
 }
 
 #ifdef PNG_oFFs_SUPPORTED
@@ -879,10 +890,10 @@
       *offset_x = info_ptr->x_offset;
       *offset_y = info_ptr->y_offset;
       *unit_type = (int)info_ptr->offset_unit_type;
-      return (PNG_INFO_oFFs);
+      return PNG_INFO_oFFs;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -906,10 +917,10 @@
       *nparams = (int)info_ptr->pcal_nparams;
       *units = info_ptr->pcal_units;
       *params = info_ptr->pcal_params;
-      return (PNG_INFO_pCAL);
+      return PNG_INFO_pCAL;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -921,6 +932,8 @@
 png_get_sCAL_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_fixed_point *width, png_fixed_point *height)
 {
+   png_debug1(1, "in %s retrieval function", "sCAL");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
@@ -932,10 +945,10 @@
       *width = png_fixed(png_ptr, atof(info_ptr->scal_s_width), "sCAL width");
       *height = png_fixed(png_ptr, atof(info_ptr->scal_s_height),
           "sCAL height");
-      return (PNG_INFO_sCAL);
+      return PNG_INFO_sCAL;
    }
 
-   return(0);
+   return 0;
 }
 #    endif /* FLOATING_ARITHMETIC */
 #  endif /* FIXED_POINT */
@@ -944,32 +957,36 @@
 png_get_sCAL(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, double *width, double *height)
 {
+   png_debug1(1, "in %s retrieval function", "sCAL(float)");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
       *unit = info_ptr->scal_unit;
       *width = atof(info_ptr->scal_s_width);
       *height = atof(info_ptr->scal_s_height);
-      return (PNG_INFO_sCAL);
+      return PNG_INFO_sCAL;
    }
 
-   return(0);
+   return 0;
 }
 #  endif /* FLOATING POINT */
 png_uint_32 PNGAPI
 png_get_sCAL_s(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_charpp width, png_charpp height)
 {
+   png_debug1(1, "in %s retrieval function", "sCAL(str)");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
       *unit = info_ptr->scal_unit;
       *width = info_ptr->scal_s_width;
       *height = info_ptr->scal_s_height;
-      return (PNG_INFO_sCAL);
+      return PNG_INFO_sCAL;
    }
 
-   return(0);
+   return 0;
 }
 #endif /* sCAL */
 
@@ -1004,7 +1021,7 @@
       }
    }
 
-   return (retval);
+   return retval;
 }
 #endif /* pHYs */
 
@@ -1020,10 +1037,10 @@
       *palette = info_ptr->palette;
       *num_palette = info_ptr->num_palette;
       png_debug1(3, "num_palette = %d", *num_palette);
-      return (PNG_INFO_PLTE);
+      return PNG_INFO_PLTE;
    }
 
-   return (0);
+   return 0;
 }
 
 #ifdef PNG_sBIT_SUPPORTED
@@ -1037,10 +1054,10 @@
        (info_ptr->valid & PNG_INFO_sBIT) != 0 && sig_bit != NULL)
    {
       *sig_bit = &(info_ptr->sig_bit);
-      return (PNG_INFO_sBIT);
+      return PNG_INFO_sBIT;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -1051,7 +1068,7 @@
 {
    if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
    {
-      png_debug1(1, "in 0x%lx retrieval function",
+      png_debug1(1, "in text retrieval function, chunk typeid = 0x%lx",
          (unsigned long)png_ptr->chunk_name);
 
       if (text_ptr != NULL)
@@ -1066,7 +1083,7 @@
    if (num_text != NULL)
       *num_text = 0;
 
-   return(0);
+   return 0;
 }
 #endif
 
@@ -1081,10 +1098,10 @@
        (info_ptr->valid & PNG_INFO_tIME) != 0 && mod_time != NULL)
    {
       *mod_time = &(info_ptr->mod_time);
-      return (PNG_INFO_tIME);
+      return PNG_INFO_tIME;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
@@ -1094,11 +1111,12 @@
     png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 {
    png_uint_32 retval = 0;
+
+   png_debug1(1, "in %s retrieval function", "tRNS");
+
    if (png_ptr != NULL && info_ptr != NULL &&
        (info_ptr->valid & PNG_INFO_tRNS) != 0)
    {
-      png_debug1(1, "in %s retrieval function", "tRNS");
-
       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
          if (trans_alpha != NULL)
@@ -1130,7 +1148,7 @@
       }
    }
 
-   return (retval);
+   return retval;
 }
 #endif
 
@@ -1145,13 +1163,13 @@
       return info_ptr->unknown_chunks_num;
    }
 
-   return (0);
+   return 0;
 }
 #endif
 
 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
 png_byte PNGAPI
-png_get_rgb_to_gray_status (png_const_structrp png_ptr)
+png_get_rgb_to_gray_status(png_const_structrp png_ptr)
 {
    return (png_byte)(png_ptr ? png_ptr->rgb_to_gray_status : 0);
 }
@@ -1192,27 +1210,27 @@
 /* These functions were added to libpng 1.2.6 and were enabled
  * by default in libpng-1.4.0 */
 png_uint_32 PNGAPI
-png_get_user_width_max (png_const_structrp png_ptr)
+png_get_user_width_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_width_max : 0);
 }
 
 png_uint_32 PNGAPI
-png_get_user_height_max (png_const_structrp png_ptr)
+png_get_user_height_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_height_max : 0);
 }
 
 /* This function was added to libpng 1.4.0 */
 png_uint_32 PNGAPI
-png_get_chunk_cache_max (png_const_structrp png_ptr)
+png_get_chunk_cache_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_chunk_cache_max : 0);
 }
 
 /* This function was added to libpng 1.4.1 */
 png_alloc_size_t PNGAPI
-png_get_chunk_malloc_max (png_const_structrp png_ptr)
+png_get_chunk_malloc_max(png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
 }
@@ -1221,13 +1239,13 @@
 /* These functions were added to libpng 1.4.0 */
 #ifdef PNG_IO_STATE_SUPPORTED
 png_uint_32 PNGAPI
-png_get_io_state (png_const_structrp png_ptr)
+png_get_io_state(png_const_structrp png_ptr)
 {
    return png_ptr->io_state;
 }
 
 png_uint_32 PNGAPI
-png_get_io_chunk_type (png_const_structrp png_ptr)
+png_get_io_chunk_type(png_const_structrp png_ptr)
 {
    return png_ptr->chunk_name;
 }
@@ -1241,7 +1259,7 @@
    if (png_ptr != NULL && info_ptr != NULL)
       return png_ptr->num_palette_max;
 
-   return (-1);
+   return -1;
 }
 #  endif
 #endif
diff --git a/pngpread.c b/pngpread.c
index e283627..ffab19c 100644
--- a/pngpread.c
+++ b/pngpread.c
@@ -1,7 +1,7 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -145,10 +145,10 @@
        num_to_check);
    png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check);
 
-   if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+   if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check) != 0)
    {
       if (num_checked < 4 &&
-          png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+          png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4) != 0)
          png_error(png_ptr, "Not a PNG file");
 
       else
@@ -295,6 +295,14 @@
    }
 
 #endif
+#ifdef PNG_READ_eXIf_SUPPORTED
+   else if (png_ptr->chunk_name == png_eXIf)
+   {
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
+      png_handle_eXIf(png_ptr, info_ptr, png_ptr->push_length);
+   }
+
+#endif
 #ifdef PNG_READ_sRGB_SUPPORTED
    else if (chunk_name == png_sRGB)
    {
@@ -1089,7 +1097,7 @@
 png_get_progressive_ptr(png_const_structrp png_ptr)
 {
    if (png_ptr == NULL)
-      return (NULL);
+      return NULL;
 
    return png_ptr->io_ptr;
 }
diff --git a/pngpriv.h b/pngpriv.h
index 43b00b1..50368c0 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -1,7 +1,7 @@
 
 /* pngpriv.h - private declarations for use inside libpng
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -36,7 +36,7 @@
  * still required (as of 2011-05-02.)
  */
 #ifndef _POSIX_SOURCE
-# define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
+#  define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
 #endif
 
 #ifndef PNG_VERSION_INFO_ONLY
@@ -175,7 +175,7 @@
 #     else /* !defined __ARM_NEON__ */
          /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
           */
-#        if !defined(__aarch64__)
+#        if !defined(__aarch64__) && !defined(_M_ARM64)
             /* The assembler code currently does not work on ARM64 */
 #          define PNG_ARM_NEON_IMPLEMENTATION 2
 #        endif /* __aarch64__ */
@@ -186,16 +186,32 @@
       /* Use the intrinsics code by default. */
 #     define PNG_ARM_NEON_IMPLEMENTATION 1
 #  endif
+#else /* PNG_ARM_NEON_OPT == 0 */
+#     define PNG_ARM_NEON_IMPLEMENTATION 0
 #endif /* PNG_ARM_NEON_OPT > 0 */
 
 #ifndef PNG_MIPS_MSA_OPT
-#  if defined(__mips_msa) && (__mips_isa_rev >= 5) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
+#  if defined(__mips_msa) && (__mips_isa_rev >= 5) && \
+   defined(PNG_ALIGNED_MEMORY_SUPPORTED)
 #     define PNG_MIPS_MSA_OPT 2
 #  else
 #     define PNG_MIPS_MSA_OPT 0
 #  endif
 #endif
 
+#ifndef PNG_MIPS_MMI_OPT
+#  ifdef PNG_MIPS_MMI
+#    if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64) && \
+     defined(PNG_ALIGNED_MEMORY_SUPPORTED)
+#       define PNG_MIPS_MMI_OPT 1
+#    else
+#       define PNG_MIPS_MMI_OPT 0
+#    endif
+#  else
+#    define PNG_MIPS_MMI_OPT 0
+#  endif
+#endif
+
 #ifndef PNG_POWERPC_VSX_OPT
 #  if defined(__PPC64__) && defined(__ALTIVEC__) && defined(__VSX__)
 #     define PNG_POWERPC_VSX_OPT 2
@@ -204,13 +220,21 @@
 #  endif
 #endif
 
+#ifndef PNG_LOONGARCH_LSX_OPT
+#  if defined(__loongarch_sx)
+#     define PNG_LOONGARCH_LSX_OPT 1
+#  else
+#     define PNG_LOONGARCH_LSX_OPT 0
+#  endif
+#endif
+
 #ifndef PNG_INTEL_SSE_OPT
 #   ifdef PNG_INTEL_SSE
       /* Only check for SSE if the build configuration has been modified to
        * enable SSE optimizations.  This means that these optimizations will
        * be off by default.  See contrib/intel for more details.
        */
-#     if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
+#      if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
        defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
        (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
 #         define PNG_INTEL_SSE_OPT 1
@@ -247,7 +271,6 @@
 #endif
 
 #if PNG_MIPS_MSA_OPT > 0
-#  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_msa
 #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
 #     if defined(__mips_msa)
 #        if defined(__clang__)
@@ -263,14 +286,41 @@
 
 #  ifndef PNG_MIPS_MSA_IMPLEMENTATION
 #     define PNG_MIPS_MSA_IMPLEMENTATION 1
+#     define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
 #  endif
+#else
+#  define PNG_MIPS_MSA_IMPLEMENTATION 0
 #endif /* PNG_MIPS_MSA_OPT > 0 */
 
+#if PNG_MIPS_MMI_OPT > 0
+#  ifndef PNG_MIPS_MMI_IMPLEMENTATION
+#     if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64)
+#        define PNG_MIPS_MMI_IMPLEMENTATION 2
+#     else /* !defined __mips_loongson_mmi  || _MIPS_SIM != _ABI64 */
+#        define PNG_MIPS_MMI_IMPLEMENTATION 0
+#     endif /* __mips_loongson_mmi  && _MIPS_SIM == _ABI64 */
+#  endif /* !PNG_MIPS_MMI_IMPLEMENTATION */
+
+#   if PNG_MIPS_MMI_IMPLEMENTATION > 0
+#      define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
+#   endif
+#else
+#   define PNG_MIPS_MMI_IMPLEMENTATION 0
+#endif /* PNG_MIPS_MMI_OPT > 0 */
+
 #if PNG_POWERPC_VSX_OPT > 0
 #  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
 #  define PNG_POWERPC_VSX_IMPLEMENTATION 1
+#else
+#  define PNG_POWERPC_VSX_IMPLEMENTATION 0
 #endif
 
+#if PNG_LOONGARCH_LSX_OPT > 0
+#   define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_lsx
+#   define PNG_LOONGARCH_LSX_IMPLEMENTATION 1
+#else
+#   define PNG_LOONGARCH_LSX_IMPLEMENTATION 0
+#endif
 
 /* Is this a build of a DLL where compilation of the object modules requires
  * different preprocessor settings to those required for a simple library?  If
@@ -493,16 +543,7 @@
    static_cast<type>(static_cast<const void*>(value))
 #else
 #  define png_voidcast(type, value) (value)
-#  ifdef _WIN64
-#     ifdef __GNUC__
-         typedef unsigned long long png_ptruint;
-#     else
-         typedef unsigned __int64 png_ptruint;
-#     endif
-#  else
-      typedef unsigned long png_ptruint;
-#  endif
-#  define png_constcast(type, value) ((type)(png_ptruint)(const void*)(value))
+#  define png_constcast(type, value) ((type)(void*)(const void*)(value))
 #  define png_aligncast(type, value) ((void*)(value))
 #  define png_aligncastconst(type, value) ((const void*)(value))
 #endif /* __cplusplus */
@@ -518,18 +559,8 @@
     */
 #  include <float.h>
 
-#  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
-    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
-   /* We need to check that <math.h> hasn't already been included earlier
-    * as it seems it doesn't agree with <fp.h>, yet we should really use
-    * <fp.h> if possible.
-    */
-#    if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
-#      include <fp.h>
-#    endif
-#  else
-#    include <math.h>
-#  endif
+#  include <math.h>
+
 #  if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
    /* Amiga SAS/C: We must include builtin FPU functions when compiling using
     * MATH=68881
@@ -544,9 +575,8 @@
 #  include <alloc.h>
 #endif
 
-#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
-    defined(_WIN32) || defined(__WIN32__)
-#  include <windows.h>  /* defines _WINDOWS_ macro */
+#if defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
+#  include <windows.h>
 #endif
 #endif /* PNG_VERSION_INFO_ONLY */
 
@@ -555,24 +585,20 @@
  * functions that are passed far data must be model-independent.
  */
 
-/* Memory model/platform independent fns */
+/* Platform-independent functions */
 #ifndef PNG_ABORT
-#  ifdef _WINDOWS_
-#    define PNG_ABORT() ExitProcess(0)
-#  else
-#    define PNG_ABORT() abort()
-#  endif
+#  define PNG_ABORT() abort()
 #endif
 
 /* These macros may need to be architecture dependent. */
-#define PNG_ALIGN_NONE   0 /* do not use data alignment */
-#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
+#define PNG_ALIGN_NONE      0 /* do not use data alignment */
+#define PNG_ALIGN_ALWAYS    1 /* assume unaligned accesses are OK */
 #ifdef offsetof
-#  define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
+#  define PNG_ALIGN_OFFSET  2 /* use offsetof to determine alignment */
 #else
 #  define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
 #endif
-#define PNG_ALIGN_SIZE   3 /* use sizeof to determine alignment */
+#define PNG_ALIGN_SIZE      3 /* use sizeof to determine alignment */
 
 #ifndef PNG_ALIGN_TYPE
    /* Default to using aligned access optimizations and requiring alignment to a
@@ -586,25 +612,25 @@
    /* This is used because in some compiler implementations non-aligned
     * structure members are supported, so the offsetof approach below fails.
     * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
-    * is good for performance.  Do not do this unless you have tested the result
-    * and understand it.
+    * is good for performance.  Do not do this unless you have tested the
+    * result and understand it.
     */
-#  define png_alignof(type) (sizeof (type))
+#  define png_alignof(type) (sizeof(type))
 #else
 #  if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
-#     define png_alignof(type) offsetof(struct{char c; type t;}, t)
+#    define png_alignof(type) offsetof(struct{char c; type t;}, t)
 #  else
-#     if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
-#        define png_alignof(type) (1)
-#     endif
-      /* Else leave png_alignof undefined to prevent use thereof */
+#    if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
+#      define png_alignof(type) 1
+#    endif
+     /* Else leave png_alignof undefined to prevent use thereof */
 #  endif
 #endif
 
-/* This implicitly assumes alignment is always to a power of 2. */
+/* This implicitly assumes alignment is always a multiple of 2. */
 #ifdef png_alignof
-#  define png_isaligned(ptr, type)\
-   ((((uintptr_t)ptr) & (png_alignof(type)-1)) == 0)
+#  define png_isaligned(ptr, type) \
+   (((type)(size_t)((const void*)(ptr)) & (type)(png_alignof(type)-1)) == 0)
 #else
 #  define png_isaligned(ptr, type) 0
 #endif
@@ -635,7 +661,7 @@
 #define PNG_BACKGROUND_IS_GRAY     0x800U
 #define PNG_HAVE_PNG_SIGNATURE    0x1000U
 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */
-                   /*             0x4000U (unused) */
+#define PNG_WROTE_eXIf            0x4000U
 #define PNG_IS_READ_STRUCT        0x8000U /* Else is a write struct */
 
 /* Flags for the transformations the PNG library does on the image data */
@@ -1315,7 +1341,7 @@
     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
 #endif
 
-#if PNG_MIPS_MSA_OPT > 0
+#if PNG_MIPS_MSA_IMPLEMENTATION == 1
 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_msa,(png_row_infop row_info,
     png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_msa,(png_row_infop
@@ -1332,6 +1358,23 @@
     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
 #endif
 
+#if PNG_MIPS_MMI_IMPLEMENTATION > 0
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_mmi,(png_row_infop row_info,
+    png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_mmi,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+#endif
+
 #if PNG_POWERPC_VSX_OPT > 0
 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_vsx,(png_row_infop row_info,
     png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
@@ -1364,6 +1407,23 @@
     row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
 #endif
 
+#if PNG_LOONGARCH_LSX_IMPLEMENTATION == 1
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_lsx,(png_row_infop
+    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
+#endif
+
 /* Choose the best filter to use and filter the row data */
 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
     png_row_infop row_info),PNG_EMPTY);
@@ -1919,7 +1979,7 @@
  */
 #define PNG_FP_INVALID  512  /* Available for callers as a distinct value */
 
-/* Result codes for the parser (boolean - true meants ok, false means
+/* Result codes for the parser (boolean - true means ok, false means
  * not ok yet.)
  */
 #define PNG_FP_MAYBE      0  /* The number may be valid in the future */
@@ -1955,7 +2015,7 @@
  * the problem character.)  This has not been tested within libpng.
  */
 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
-   size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
+   size_t size, int *statep, size_t *whereami),PNG_EMPTY);
 
 /* This is the same but it checks a complete string and returns true
  * only if it just contains a floating point number.  As of 1.5.4 this
@@ -2103,17 +2163,27 @@
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
 
-#if PNG_MIPS_MSA_OPT > 0
-PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_msa,
+#if PNG_MIPS_MSA_IMPLEMENTATION == 1
+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
 
+#  if PNG_MIPS_MMI_IMPLEMENTATION > 0
+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
+   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
+#  endif
+
 #  if PNG_INTEL_SSE_IMPLEMENTATION > 0
 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #  endif
 #endif
 
+#if PNG_LOONGARCH_LSX_OPT > 0
+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_lsx,
+    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
+#endif
+
 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
    png_const_charp key, png_bytep new_key), PNG_EMPTY);
 
diff --git a/pngread.c b/pngread.c
index 8fa7d9f..07a39df 100644
--- a/pngread.c
+++ b/pngread.c
@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -568,7 +568,11 @@
 #endif
 
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   if (png_ptr->transformations)
+   if (png_ptr->transformations
+#     ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+         || png_ptr->num_palette_max >= 0
+#     endif
+      )
       png_do_read_transformations(png_ptr, &row_info);
 #endif
 
@@ -785,7 +789,7 @@
 #ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
    /* Report invalid palette index; added at libng-1.5.10 */
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-       png_ptr->num_palette_max > png_ptr->num_palette)
+       png_ptr->num_palette_max >= png_ptr->num_palette)
       png_benign_error(png_ptr, "Read palette index exceeding num_palette");
 #endif
 
@@ -1049,6 +1053,8 @@
 png_read_png(png_structrp png_ptr, png_inforp info_ptr,
     int transforms, voidp params)
 {
+   png_debug(1, "in png_read_png");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
@@ -3452,7 +3458,6 @@
 
             for (pass = 0; pass < passes; ++pass)
             {
-               png_bytep row = png_voidcast(png_bytep, display->first_row);
                unsigned int     startx, stepx, stepy;
                png_uint_32      y;
 
@@ -3557,8 +3562,6 @@
 
                         inrow += 2; /* gray and alpha channel */
                      }
-
-                     row += display->row_bytes;
                   }
                }
             }
@@ -3765,13 +3768,13 @@
          mode = PNG_ALPHA_PNG;
          output_gamma = PNG_DEFAULT_sRGB;
       }
-      
+
       if ((change & PNG_FORMAT_FLAG_ASSOCIATED_ALPHA) != 0)
       {
          mode = PNG_ALPHA_OPTIMIZED;
          change &= ~PNG_FORMAT_FLAG_ASSOCIATED_ALPHA;
       }
-      
+
       /* If 'do_local_background' is set check for the presence of gamma
        * correction; this is part of the work-round for the libpng bug
        * described above.
diff --git a/pngrtran.c b/pngrtran.c
index 238f5af..74cca47 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -290,21 +290,20 @@
    int compose = 0;
    png_fixed_point file_gamma;
 
-   png_debug(1, "in png_set_alpha_mode");
+   png_debug(1, "in png_set_alpha_mode_fixed");
 
    if (png_rtran_ok(png_ptr, 0) == 0)
       return;
 
    output_gamma = translate_gamma_flags(png_ptr, output_gamma, 1/*screen*/);
 
-   /* Validate the value to ensure it is in a reasonable range. The value
+   /* Validate the value to ensure it is in a reasonable range.  The value
     * is expected to be 1 or greater, but this range test allows for some
-    * viewing correction values.  The intent is to weed out users of this API
-    * who use the inverse of the gamma value accidentally!  Since some of these
-    * values are reasonable this may have to be changed:
+    * viewing correction values.  The intent is to weed out the API users
+    * who might use the inverse of the gamma value accidentally!
     *
-    * 1.6.x: changed from 0.07..3 to 0.01..100 (to accommodate the optimal 16-bit
-    * gamma of 36, and its reciprocal.)
+    * In libpng 1.6.x, we changed from 0.07..3 to 0.01..100, to accommodate
+    * the optimal 16-bit gamma of 36 and its reciprocal.
     */
    if (output_gamma < 1000 || output_gamma > 10000000)
       png_error(png_ptr, "output gamma out of expected range");
@@ -970,7 +969,7 @@
 png_set_rgb_to_gray_fixed(png_structrp png_ptr, int error_action,
     png_fixed_point red, png_fixed_point green)
 {
-   png_debug(1, "in png_set_rgb_to_gray");
+   png_debug(1, "in png_set_rgb_to_gray_fixed");
 
    /* Need the IHDR here because of the check on color_type below. */
    /* TODO: fix this */
diff --git a/pngrutil.c b/pngrutil.c
index fecbb4f..d31dc21 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -26,7 +26,7 @@
    if (uval > PNG_UINT_31_MAX)
       png_error(png_ptr, "PNG unsigned integer out of range");
 
-   return (uval);
+   return uval;
 }
 
 #if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_READ_cHRM_SUPPORTED)
@@ -140,7 +140,7 @@
    if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check) != 0)
    {
       if (num_checked < 4 &&
-          png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+          png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4) != 0)
          png_error(png_ptr, "Not a PNG file");
       else
          png_error(png_ptr, "PNG file corrupted by ASCII conversion");
@@ -171,7 +171,7 @@
    /* Put the chunk name into png_ptr->chunk_name. */
    png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(buf+4);
 
-   png_debug2(0, "Reading %lx chunk, length = %lu",
+   png_debug2(0, "Reading chunk typeid = 0x%lx, length = %lu",
        (unsigned long)png_ptr->chunk_name, (unsigned long)length);
 
    /* Reset the crc and run it over the chunk name. */
@@ -238,10 +238,10 @@
       else
          png_chunk_error(png_ptr, "CRC error");
 
-      return (1);
+      return 1;
    }
 
-   return (0);
+   return 0;
 }
 
 /* Compare the CRC stored in the PNG file with that calculated by libpng from
@@ -277,11 +277,11 @@
    if (need_crc != 0)
    {
       crc = png_get_uint_32(crc_bytes);
-      return ((int)(crc != png_ptr->crc));
+      return crc != png_ptr->crc;
    }
 
    else
-      return (0);
+      return 0;
 }
 
 #if defined(PNG_READ_iCCP_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) ||\
@@ -302,7 +302,6 @@
    if (buffer != NULL && new_size > png_ptr->read_buffer_size)
    {
       png_ptr->read_buffer = NULL;
-      png_ptr->read_buffer = NULL;
       png_ptr->read_buffer_size = 0;
       png_free(png_ptr, buffer);
       buffer = NULL;
@@ -422,8 +421,7 @@
             png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED;
       }
 
-#if ZLIB_VERNUM >= 0x1290 && \
-   defined(PNG_SET_OPTION_SUPPORTED) && defined(PNG_IGNORE_ADLER32)
+#ifdef PNG_DISABLE_ADLER32_CHECK_SUPPORTED
       if (((png_ptr->options >> PNG_IGNORE_ADLER32) & 3) == PNG_OPTION_ON)
          /* Turn off validation of the ADLER32 checksum in IDAT chunks */
          ret = inflateValidate(&png_ptr->zstream, 0);
@@ -2076,21 +2074,22 @@
       png_byte buf[1];
       png_crc_read(png_ptr, buf, 1);
       info_ptr->eXIf_buf[i] = buf[0];
-      if (i == 1 && buf[0] != 'M' && buf[0] != 'I'
-                 && info_ptr->eXIf_buf[0] != buf[0])
+      if (i == 1)
       {
-         png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "incorrect byte-order specifier");
-         png_free(png_ptr, info_ptr->eXIf_buf);
-         info_ptr->eXIf_buf = NULL;
-         return;
+         if ((buf[0] != 'M' && buf[0] != 'I') ||
+             (info_ptr->eXIf_buf[0] != buf[0]))
+         {
+            png_crc_finish(png_ptr, length - 2);
+            png_chunk_benign_error(png_ptr, "incorrect byte-order specifier");
+            png_free(png_ptr, info_ptr->eXIf_buf);
+            info_ptr->eXIf_buf = NULL;
+            return;
+         }
       }
    }
 
-   if (png_crc_finish(png_ptr, 0) != 0)
-      return;
-
-   png_set_eXIf_1(png_ptr, info_ptr, length, info_ptr->eXIf_buf);
+   if (png_crc_finish(png_ptr, 0) == 0)
+      png_set_eXIf_1(png_ptr, info_ptr, length, info_ptr->eXIf_buf);
 
    png_free(png_ptr, info_ptr->eXIf_buf);
    info_ptr->eXIf_buf = NULL;
@@ -2126,8 +2125,9 @@
 
    num = length / 2 ;
 
-   if (num != (unsigned int) png_ptr->num_palette ||
-       num > (unsigned int) PNG_MAX_PALETTE_LENGTH)
+   if (length != num * 2 ||
+       num != (unsigned int)png_ptr->num_palette ||
+       num > (unsigned int)PNG_MAX_PALETTE_LENGTH)
    {
       png_crc_finish(png_ptr, length);
       png_chunk_benign_error(png_ptr, "invalid");
@@ -3185,7 +3185,7 @@
    {
       png_debug2(0," length = %lu, limit = %lu",
          (unsigned long)length,(unsigned long)limit);
-      png_chunk_error(png_ptr, "chunk data is too large");
+      png_benign_error(png_ptr, "chunk data is too large");
    }
 }
 
@@ -4621,14 +4621,13 @@
        */
       {
          png_bytep temp = png_ptr->big_row_buf + 32;
-         int extra = (int)(((uintptr_t)temp) & 0x0f);
+         size_t extra = (size_t)temp & 0x0f;
          png_ptr->row_buf = temp - extra - 1/*filter byte*/;
 
          temp = png_ptr->big_prev_row + 32;
-         extra = (int)(((uintptr_t)temp) & 0x0f);
+         extra = (size_t)temp & 0x0f;
          png_ptr->prev_row = temp - extra - 1/*filter byte*/;
       }
-
 #else
       /* Use 31 bytes of padding before and 17 bytes after row_buf. */
       png_ptr->row_buf = png_ptr->big_row_buf + 31;
diff --git a/pngset.c b/pngset.c
index ec75dbe..eb1c8c7 100644
--- a/pngset.c
+++ b/pngset.c
@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -137,46 +137,40 @@
 #ifdef PNG_eXIf_SUPPORTED
 void PNGAPI
 png_set_eXIf(png_const_structrp png_ptr, png_inforp info_ptr,
-    png_bytep eXIf_buf)
+    png_bytep exif)
 {
   png_warning(png_ptr, "png_set_eXIf does not work; use png_set_eXIf_1");
   PNG_UNUSED(info_ptr)
-  PNG_UNUSED(eXIf_buf)
+  PNG_UNUSED(exif)
 }
 
 void PNGAPI
 png_set_eXIf_1(png_const_structrp png_ptr, png_inforp info_ptr,
-    png_uint_32 num_exif, png_bytep eXIf_buf)
+    png_uint_32 num_exif, png_bytep exif)
 {
-   int i;
+   png_bytep new_exif;
 
    png_debug1(1, "in %s storage function", "eXIf");
 
-   if (png_ptr == NULL || info_ptr == NULL)
+   if (png_ptr == NULL || info_ptr == NULL ||
+       (png_ptr->mode & PNG_WROTE_eXIf) != 0)
       return;
 
-   if (info_ptr->exif)
-   {
-      png_free(png_ptr, info_ptr->exif);
-      info_ptr->exif = NULL;
-   }
+   new_exif = png_voidcast(png_bytep, png_malloc_warn(png_ptr, num_exif));
 
-   info_ptr->num_exif = num_exif;
-
-   info_ptr->exif = png_voidcast(png_bytep, png_malloc_warn(png_ptr,
-       info_ptr->num_exif));
-
-   if (info_ptr->exif == NULL)
+   if (new_exif == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for eXIf chunk data");
       return;
    }
 
+   memcpy(new_exif, exif, (size_t)num_exif);
+
+   png_free_data(png_ptr, info_ptr, PNG_FREE_EXIF, 0);
+
+   info_ptr->num_exif = num_exif;
+   info_ptr->exif = new_exif;
    info_ptr->free_me |= PNG_FREE_EXIF;
-
-   for (i = 0; i < (int) info_ptr->num_exif; i++)
-      info_ptr->exif[i] = eXIf_buf[i];
-
    info_ptr->valid |= PNG_INFO_eXIf;
 }
 #endif /* eXIf */
@@ -237,15 +231,13 @@
    if (info_ptr->hist == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for hIST chunk data");
-
       return;
    }
 
-   info_ptr->free_me |= PNG_FREE_HIST;
-
    for (i = 0; i < info_ptr->num_palette; i++)
       info_ptr->hist[i] = hist[i];
 
+   info_ptr->free_me |= PNG_FREE_HIST;
    info_ptr->valid |= PNG_INFO_hIST;
 }
 #endif
@@ -367,6 +359,8 @@
 
    memcpy(info_ptr->pcal_purpose, purpose, length);
 
+   info_ptr->free_me |= PNG_FREE_PCAL;
+
    png_debug(3, "storing X0, X1, type, and nparams in info");
    info_ptr->pcal_X0 = X0;
    info_ptr->pcal_X1 = X1;
@@ -383,7 +377,6 @@
    if (info_ptr->pcal_units == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for pCAL units");
-
       return;
    }
 
@@ -395,7 +388,6 @@
    if (info_ptr->pcal_params == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for pCAL params");
-
       return;
    }
 
@@ -413,7 +405,6 @@
       if (info_ptr->pcal_params[i] == NULL)
       {
          png_warning(png_ptr, "Insufficient memory for pCAL parameter");
-
          return;
       }
 
@@ -421,7 +412,6 @@
    }
 
    info_ptr->valid |= PNG_INFO_pCAL;
-   info_ptr->free_me |= PNG_FREE_PCAL;
 }
 #endif
 
@@ -478,18 +468,17 @@
 
    if (info_ptr->scal_s_height == NULL)
    {
-      png_free (png_ptr, info_ptr->scal_s_width);
+      png_free(png_ptr, info_ptr->scal_s_width);
       info_ptr->scal_s_width = NULL;
 
       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
-
       return;
    }
 
    memcpy(info_ptr->scal_s_height, sheight, lengthh);
 
-   info_ptr->valid |= PNG_INFO_sCAL;
    info_ptr->free_me |= PNG_FREE_SCAL;
+   info_ptr->valid |= PNG_INFO_sCAL;
 }
 
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
@@ -625,11 +614,10 @@
    if (num_palette > 0)
       memcpy(png_ptr->palette, palette, (unsigned int)num_palette *
           (sizeof (png_color)));
+
    info_ptr->palette = png_ptr->palette;
    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
-
    info_ptr->free_me |= PNG_FREE_PLTE;
-
    info_ptr->valid |= PNG_INFO_PLTE;
 }
 
@@ -775,11 +763,11 @@
 {
    int i;
 
-   png_debug1(1, "in %lx storage function", png_ptr == NULL ? 0xabadca11U :
-      (unsigned long)png_ptr->chunk_name);
+   png_debug1(1, "in text storage function, chunk typeid = 0x%lx",
+      png_ptr == NULL ? 0xabadca11UL : (unsigned long)png_ptr->chunk_name);
 
    if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
-      return(0);
+      return 0;
 
    /* Make sure we have enough space in the "text" array in info_struct
     * to hold all of the incoming text_ptr objects.  This compare can't overflow
@@ -959,7 +947,7 @@
       png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
    }
 
-   return(0);
+   return 0;
 }
 #endif
 
@@ -1019,6 +1007,9 @@
           info_ptr->trans_alpha = png_voidcast(png_bytep,
               png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
           memcpy(info_ptr->trans_alpha, trans_alpha, (size_t)num_trans);
+
+          info_ptr->free_me |= PNG_FREE_TRNS;
+          info_ptr->valid |= PNG_INFO_tRNS;
        }
        png_ptr->trans_alpha = info_ptr->trans_alpha;
    }
@@ -1051,8 +1042,8 @@
 
    if (num_trans != 0)
    {
-      info_ptr->valid |= PNG_INFO_tRNS;
       info_ptr->free_me |= PNG_FREE_TRNS;
+      info_ptr->valid |= PNG_INFO_tRNS;
    }
 }
 #endif
@@ -1072,6 +1063,8 @@
 {
    png_sPLT_tp np;
 
+   png_debug1(1, "in %s storage function", "sPLT");
+
    if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
       return;
 
@@ -1086,11 +1079,11 @@
    {
       /* Out of memory or too many chunks */
       png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
-
       return;
    }
 
    png_free(png_ptr, info_ptr->splt_palettes);
+
    info_ptr->splt_palettes = np;
    info_ptr->free_me |= PNG_FREE_SPLT;
 
@@ -1244,11 +1237,11 @@
    {
       png_chunk_report(png_ptr, "too many unknown chunks",
           PNG_CHUNK_WRITE_ERROR);
-
       return;
    }
 
    png_free(png_ptr, info_ptr->unknown_chunks);
+
    info_ptr->unknown_chunks = np; /* safe because it is initialized */
    info_ptr->free_me |= PNG_FREE_UNKN;
 
@@ -1326,7 +1319,7 @@
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
 png_uint_32 PNGAPI
-png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
+png_permit_mng_features(png_structrp png_ptr, png_uint_32 mng_features)
 {
    png_debug(1, "in png_permit_mng_features");
 
@@ -1546,7 +1539,7 @@
 png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
     png_bytepp row_pointers)
 {
-   png_debug1(1, "in %s storage function", "rows");
+   png_debug(1, "in png_set_rows");
 
    if (png_ptr == NULL || info_ptr == NULL)
       return;
@@ -1565,6 +1558,8 @@
 void PNGAPI
 png_set_compression_buffer_size(png_structrp png_ptr, size_t size)
 {
+   png_debug(1, "in png_set_compression_buffer_size");
+
    if (png_ptr == NULL)
       return;
 
@@ -1633,9 +1628,11 @@
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
 /* This function was added to libpng 1.2.6 */
 void PNGAPI
-png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
+png_set_user_limits(png_structrp png_ptr, png_uint_32 user_width_max,
     png_uint_32 user_height_max)
 {
+   png_debug(1, "in png_set_user_limits");
+
    /* Images with dimensions larger than these limits will be
     * rejected by png_set_IHDR().  To accept any PNG datastream
     * regardless of dimensions, set both limits to 0x7fffffff.
@@ -1649,17 +1646,21 @@
 
 /* This function was added to libpng 1.4.0 */
 void PNGAPI
-png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
+png_set_chunk_cache_max(png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
 {
+   png_debug(1, "in png_set_chunk_cache_max");
+
    if (png_ptr != NULL)
       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
 }
 
 /* This function was added to libpng 1.4.1 */
 void PNGAPI
-png_set_chunk_malloc_max (png_structrp png_ptr,
+png_set_chunk_malloc_max(png_structrp png_ptr,
     png_alloc_size_t user_chunk_malloc_max)
 {
+   png_debug(1, "in png_set_chunk_malloc_max");
+
    if (png_ptr != NULL)
       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
diff --git a/pngstruct.h b/pngstruct.h
index 8bdc7ce..e591d94 100644
--- a/pngstruct.h
+++ b/pngstruct.h
@@ -1,7 +1,7 @@
 
 /* pngstruct.h - header file for PNG reference library
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2022 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -334,18 +334,8 @@
    size_t current_buffer_size;       /* amount of data now in current_buffer */
    int process_mode;                 /* what push library is currently doing */
    int cur_palette;                  /* current push library palette index */
-
 #endif /* PROGRESSIVE_READ */
 
-#if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
-/* For the Borland special 64K segment handler */
-   png_bytepp offset_table_ptr;
-   png_bytep offset_table;
-   png_uint_16 offset_table_number;
-   png_uint_16 offset_table_count;
-   png_uint_16 offset_table_count_free;
-#endif
-
 #ifdef PNG_READ_QUANTIZE_SUPPORTED
    png_bytep palette_lookup; /* lookup table for quantizing */
    png_bytep quantize_index; /* index translation for palette files */
diff --git a/pngtest.c b/pngtest.c
index dd5113d..a94b449 100644
--- a/pngtest.c
+++ b/pngtest.c
@@ -1,7 +1,7 @@
 
-/* pngtest.c - a simple test program to test libpng
+/* pngtest.c - a test program for libpng
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -37,73 +37,91 @@
 #include <stdlib.h>
 #include <string.h>
 
-/* Defined so I can write to a file on gui/windowing platforms */
-/*  #define STDERR stderr  */
-#define STDERR stdout   /* For DOS */
+#ifdef PNG_ZLIB_HEADER
+#  include PNG_ZLIB_HEADER /* defined by pnglibconf.h from 1.7 */
+#else
+#  include <zlib.h>
+#endif
 
 #include "png.h"
 
-/* Known chunks that exist in pngtest.png must be supported or pngtest will fail
- * simply as a result of re-ordering them.  This may be fixed in 1.7
+/* Generate a compiler error if there is an old png.h in the search path. */
+typedef png_libpng_version_1_6_43_git Your_png_h_is_not_version_1_6_43_git;
+
+/* Ensure that all version numbers in png.h are consistent with one another. */
+#if (PNG_LIBPNG_VER != PNG_LIBPNG_VER_MAJOR * 10000 + \
+                       PNG_LIBPNG_VER_MINOR * 100 + \
+                       PNG_LIBPNG_VER_RELEASE) || \
+    (PNG_LIBPNG_VER_SHAREDLIB != PNG_LIBPNG_VER_MAJOR * 10 + \
+                                 PNG_LIBPNG_VER_MINOR) || \
+    (PNG_LIBPNG_VER_SHAREDLIB != PNG_LIBPNG_VER_SONUM) || \
+    (PNG_LIBPNG_VER_SHAREDLIB != PNG_LIBPNG_VER_DLLNUM)
+#  error "Inconsistent version numbers in png.h"
+#endif
+
+/* In version 1.6.1, we added support for the configure test harness, which
+ * uses 77 to indicate a skipped test. On the other hand, in cmake build tests,
+ * we still need to succeed on a skipped test, so:
+ */
+#if defined(HAVE_CONFIG_H)
+#  define SKIP 77
+#else
+#  define SKIP 0
+#endif
+
+/* Known chunks that exist in pngtest.png must be supported, or pngtest will
+ * fail simply as a result of re-ordering them.  This may be fixed in the next
+ * generation of libpng.
  *
  * pngtest allocates a single row buffer for each row and overwrites it,
  * therefore if the write side doesn't support the writing of interlaced images
  * nothing can be done for an interlaced image (and the code below will fail
  * horribly trying to write extra data after writing garbage).
  */
-#if defined PNG_READ_SUPPORTED && /* else nothing can be done */\
-   defined PNG_READ_bKGD_SUPPORTED &&\
-   defined PNG_READ_cHRM_SUPPORTED &&\
-   defined PNG_READ_gAMA_SUPPORTED &&\
-   defined PNG_READ_oFFs_SUPPORTED &&\
-   defined PNG_READ_pCAL_SUPPORTED &&\
-   defined PNG_READ_pHYs_SUPPORTED &&\
-   defined PNG_READ_sBIT_SUPPORTED &&\
-   defined PNG_READ_sCAL_SUPPORTED &&\
-   defined PNG_READ_sRGB_SUPPORTED &&\
-   defined PNG_READ_sPLT_SUPPORTED &&\
-   defined PNG_READ_tEXt_SUPPORTED &&\
-   defined PNG_READ_tIME_SUPPORTED &&\
-   defined PNG_READ_zTXt_SUPPORTED &&\
-   (defined PNG_WRITE_INTERLACING_SUPPORTED || PNG_LIBPNG_VER >= 10700)
-
-#ifdef PNG_ZLIB_HEADER
-#  include PNG_ZLIB_HEADER /* defined by pnglibconf.h from 1.7 */
-#else
-#  include "zlib.h"
-#endif
+#if defined PNG_READ_SUPPORTED && /* else nothing can be done */ \
+    defined PNG_READ_bKGD_SUPPORTED && \
+    defined PNG_READ_cHRM_SUPPORTED && \
+    defined PNG_READ_gAMA_SUPPORTED && \
+    defined PNG_READ_oFFs_SUPPORTED && \
+    defined PNG_READ_pCAL_SUPPORTED && \
+    defined PNG_READ_pHYs_SUPPORTED && \
+    defined PNG_READ_sBIT_SUPPORTED && \
+    defined PNG_READ_sCAL_SUPPORTED && \
+    defined PNG_READ_sRGB_SUPPORTED && \
+    defined PNG_READ_sPLT_SUPPORTED && \
+    defined PNG_READ_tEXt_SUPPORTED && \
+    defined PNG_READ_tIME_SUPPORTED && \
+    defined PNG_READ_zTXt_SUPPORTED && \
+    (defined PNG_WRITE_INTERLACING_SUPPORTED || PNG_LIBPNG_VER >= 10700)
 
 /* Copied from pngpriv.h but only used in error messages below. */
 #ifndef PNG_ZBUF_SIZE
 #  define PNG_ZBUF_SIZE 8192
 #endif
-#define FCLOSE(file) fclose(file)
 
 #ifndef PNG_STDIO_SUPPORTED
-typedef FILE                * png_FILE_p;
+typedef FILE * png_FILE_p;
 #endif
 
-/* Makes pngtest verbose so we can find problems. */
+/* This hack was introduced for historical reasons, and we are
+ * still keeping it in libpng-1.6.x for compatibility reasons.
+ */
+#define STDERR stdout
+
 #ifndef PNG_DEBUG
 #  define PNG_DEBUG 0
 #endif
 
 #if PNG_DEBUG > 1
-#  define pngtest_debug(m)        ((void)fprintf(stderr, m "\n"))
-#  define pngtest_debug1(m,p1)    ((void)fprintf(stderr, m "\n", p1))
-#  define pngtest_debug2(m,p1,p2) ((void)fprintf(stderr, m "\n", p1, p2))
-#else
-#  define pngtest_debug(m)        ((void)0)
-#  define pngtest_debug1(m,p1)    ((void)0)
-#  define pngtest_debug2(m,p1,p2) ((void)0)
-#endif
-
-#if !PNG_DEBUG
-#  define SINGLE_ROWBUF_ALLOC  /* Makes buffer overruns easier to nail */
-#endif
-
-#ifndef PNG_UNUSED
-#  define PNG_UNUSED(param) (void)param;
+#  define pngtest_debug(m)          ((void)fprintf(stderr, m "\n"))
+#  define pngtest_debug1(m, p1)     ((void)fprintf(stderr, m "\n", p1))
+#  define pngtest_debug2(m, p1, p2) ((void)fprintf(stderr, m "\n", p1, p2))
+#elif PNG_DEBUG == 0 || PNG_DEBUG == 1
+#  define pngtest_debug(m)          ((void)0)
+#  define pngtest_debug1(m, p1)     ((void)0)
+#  define pngtest_debug2(m, p1, p2) ((void)0)
+#else /* PNG_DEBUG < 0 */
+#  error "Bad PNG_DEBUG value"
 #endif
 
 /* Turn on CPU timing
@@ -120,25 +138,8 @@
 #endif
 
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-#define PNG_tIME_STRING_LENGTH 29
 static int tIME_chunk_present = 0;
-static char tIME_string[PNG_tIME_STRING_LENGTH] = "tIME chunk is not present";
-
-#if PNG_LIBPNG_VER < 10619
-#define png_convert_to_rfc1123_buffer(ts, t) tIME_to_str(read_ptr, ts, t)
-
-static int
-tIME_to_str(png_structp png_ptr, png_charp ts, png_const_timep t)
-{
-   png_const_charp str = png_convert_to_rfc1123(png_ptr, t);
-
-   if (str == NULL)
-       return 0;
-
-   strcpy(ts, str);
-   return 1;
-}
-#endif /* older libpng */
+static char tIME_string[] = "tIME chunk is not present";
 #endif
 
 static int verbose = 0;
@@ -149,22 +150,6 @@
 static int error_count = 0; /* count calls to png_error */
 static int warning_count = 0; /* count calls to png_warning */
 
-/* Define png_jmpbuf() in case we are using a pre-1.0.6 version of libpng */
-#ifndef png_jmpbuf
-#  define png_jmpbuf(png_ptr) png_ptr->jmpbuf
-#endif
-
-/* Defines for unknown chunk handling if required. */
-#ifndef PNG_HANDLE_CHUNK_ALWAYS
-#  define PNG_HANDLE_CHUNK_ALWAYS       3
-#endif
-#ifndef PNG_HANDLE_CHUNK_IF_SAFE
-#  define PNG_HANDLE_CHUNK_IF_SAFE      2
-#endif
-
-/* Utility to save typing/errors, the argument must be a name */
-#define MEMZERO(var) ((void)memset(&var, 0, sizeof var))
-
 /* Example of using row callbacks to make a simple progress meter */
 static int status_pass = 1;
 static int status_dots_requested = 0;
@@ -173,8 +158,13 @@
 static void PNGCBAPI
 read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
 {
-   if (png_ptr == NULL || row_number > PNG_UINT_31_MAX)
-      return;
+   /* The callback should always receive correct parameters. */
+   if (png_ptr == NULL)
+      png_error(png_ptr, "read_row_callback: bad png_ptr");
+   if (row_number > PNG_UINT_31_MAX)
+      png_error(png_ptr, "read_row_callback: bad row number");
+   if (pass < 0 || pass > 7)
+      png_error(png_ptr, "read_row_callback: bad pass");
 
    if (status_pass != pass)
    {
@@ -188,7 +178,7 @@
    if (status_dots == 0)
    {
       fprintf(stdout, "\n         ");
-      status_dots=30;
+      status_dots = 30;
    }
 
    fprintf(stdout, "r");
@@ -198,8 +188,13 @@
 static void PNGCBAPI
 write_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
 {
-   if (png_ptr == NULL || row_number > PNG_UINT_31_MAX || pass > 7)
-      return;
+   /* The callback should always receive correct parameters. */
+   if (png_ptr == NULL)
+      png_error(png_ptr, "write_row_callback: bad png_ptr");
+   if (row_number > PNG_UINT_31_MAX)
+      png_error(png_ptr, "write_row_callback: bad row number");
+   if (pass < 0 || pass > 7)
+      png_error(png_ptr, "write_row_callback: bad pass");
 
    fprintf(stdout, "w");
 }
@@ -212,9 +207,13 @@
 static void PNGCBAPI
 read_user_callback(png_structp png_ptr, png_row_infop row_info, png_bytep data)
 {
-   PNG_UNUSED(png_ptr)
-   PNG_UNUSED(row_info)
-   PNG_UNUSED(data)
+   /* The callback should always receive correct parameters. */
+   if (png_ptr == NULL)
+      png_error(png_ptr, "read_user_callback: bad png_ptr");
+   if (row_info == NULL)
+      png_error(png_ptr, "read_user_callback: bad row info");
+   if (data == NULL)
+      png_error(png_ptr, "read_user_callback: bad data");
 }
 #endif
 
@@ -229,8 +228,14 @@
 count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
 {
    png_bytep dp = data;
+
+   /* The callback should always receive correct parameters. */
    if (png_ptr == NULL)
-      return;
+      png_error(png_ptr, "count_zero_samples: bad png_ptr");
+   if (row_info == NULL)
+      png_error(png_ptr, "count_zero_samples: bad row info");
+   if (data == NULL)
+      png_error(png_ptr, "count_zero_samples: bad data");
 
    /* Contents of row_info:
     *  png_uint_32 width      width of row
@@ -248,7 +253,7 @@
       int pos = 0;
       png_uint_32 n, nstop;
 
-      for (n = 0, nstop=row_info->width; n<nstop; n++)
+      for (n = 0, nstop = row_info->width; n < nstop; n++)
       {
          if (row_info->bit_depth == 1)
          {
@@ -294,7 +299,7 @@
          {
             if ((*dp | *(dp+1)) == 0)
                zero_samples++;
-            dp+=2;
+            dp += 2;
          }
       }
    }
@@ -306,7 +311,7 @@
       if (row_info->color_type > 3)
          color_channels--;
 
-      for (n = 0, nstop=row_info->width; n<nstop; n++)
+      for (n = 0, nstop = row_info->width; n < nstop; n++)
       {
          for (channel = 0; channel < color_channels; channel++)
          {
@@ -319,7 +324,7 @@
                if ((*dp | *(dp+1)) == 0)
                   zero_samples++;
 
-               dp+=2;
+               dp += 2;
             }
          }
          if (row_info->color_type > 3)
@@ -346,9 +351,6 @@
 #ifdef PNG_IO_STATE_SUPPORTED
 void
 pngtest_check_io_state(png_structp png_ptr, size_t data_length,
-    png_uint_32 io_op);
-void
-pngtest_check_io_state(png_structp png_ptr, size_t data_length,
     png_uint_32 io_op)
 {
    png_uint_32 io_state = png_get_io_state(png_ptr);
@@ -361,7 +363,7 @@
    /* Check if the buffer size specific to the current location
     * (file signature / header / data / crc) is as expected.
     */
-   switch (io_state & PNG_IO_MASK_LOC)
+   switch ((io_state & PNG_IO_MASK_LOC) != 0)
    {
    case PNG_IO_SIGNATURE:
       if (data_length > 8)
@@ -391,19 +393,18 @@
    size_t check = 0;
    png_voidp io_ptr;
 
+   if (png_ptr == NULL)
+      png_error(png_ptr, "pngtest_read_data: bad png_ptr");
+
    /* fread() returns 0 on error, so it is OK to store this in a size_t
     * instead of an int, which is what fread() actually returns.
     */
    io_ptr = png_get_io_ptr(png_ptr);
    if (io_ptr != NULL)
-   {
       check = fread(data, 1, length, (png_FILE_p)io_ptr);
-   }
 
    if (check != length)
-   {
       png_error(png_ptr, "Read Error");
-   }
 
 #ifdef PNG_IO_STATE_SUPPORTED
    pngtest_check_io_state(png_ptr, length, PNG_IO_READING);
@@ -414,8 +415,10 @@
 static void PNGCBAPI
 pngtest_flush(png_structp png_ptr)
 {
+   if (png_ptr == NULL)
+      png_error(png_ptr, "pngtest_flush: bad png_ptr");
+
    /* Do nothing; fflush() is said to be just a waste of energy. */
-   PNG_UNUSED(png_ptr)   /* Stifle compiler warning */
 }
 #endif
 
@@ -429,12 +432,13 @@
 {
    size_t check;
 
+   if (png_ptr == NULL)
+      png_error(png_ptr, "pngtest_write_data: bad png_ptr");
+
    check = fwrite(data, 1, length, (png_FILE_p)png_get_io_ptr(png_ptr));
 
    if (check != length)
-   {
       png_error(png_ptr, "Write Error");
-   }
 
 #ifdef PNG_IO_STATE_SUPPORTED
    pngtest_check_io_state(png_ptr, length, PNG_IO_WRITING);
@@ -524,7 +528,7 @@
     */
 
    if (size == 0)
-      return (NULL);
+      return NULL;
 
    /* This calls the library allocator twice, once to get the requested
       buffer and once to get a new free list entry. */
@@ -537,7 +541,7 @@
       pinfo->size = size;
       current_allocation += size;
       total_allocation += size;
-      num_allocations ++;
+      ++num_allocations;
 
       if (current_allocation > maximum_allocation)
          maximum_allocation = current_allocation;
@@ -565,7 +569,7 @@
          printf("png_malloc %lu bytes at %p\n", (unsigned long)size,
              pinfo->pointer);
 
-      return (png_voidp)(pinfo->pointer);
+      return (png_voidp)pinfo->pointer;
    }
 }
 
@@ -635,15 +639,14 @@
 /* (sTER is a public chunk not yet known by libpng.  vpAg is a private
 chunk used in ImageMagick to store "virtual page" size).  */
 
-static struct user_chunk_data
+typedef struct user_chunk_info_def
 {
    png_const_infop info_ptr;
    png_uint_32     vpAg_width, vpAg_height;
    png_byte        vpAg_units;
    png_byte        sTER_mode;
    int             location[2];
-}
-user_chunk_data;
+} user_chunk_info;
 
 /* Used for location and order; zero means nothing. */
 #define have_sTER   0x01
@@ -653,37 +656,38 @@
 #define after_IDAT  0x40
 
 static void
-init_callback_info(png_const_infop info_ptr)
+init_user_chunk_info(png_const_infop info_ptr, user_chunk_info *chunk_data)
 {
-   MEMZERO(user_chunk_data);
-   user_chunk_data.info_ptr = info_ptr;
+   memset(chunk_data, 0, sizeof(*chunk_data));
+   chunk_data->info_ptr = info_ptr;
 }
 
 static int
-set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
+set_chunk_location(png_structp png_ptr, user_chunk_info *chunk_data, int what)
 {
    int location;
 
-   if ((data->location[0] & what) != 0 || (data->location[1] & what) != 0)
-      return 0; /* already have one of these */
+   if ((chunk_data->location[0] & what) != 0 ||
+       (chunk_data->location[1] & what) != 0)
+      return 0; /* we already have one of these */
 
    /* Find where we are (the code below zeroes info_ptr to indicate that the
     * chunks before the first IDAT have been read.)
     */
-   if (data->info_ptr == NULL) /* after IDAT */
+   if (chunk_data->info_ptr == NULL) /* after IDAT */
       location = what | after_IDAT;
 
-   else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE) != 0)
+   else if (png_get_valid(png_ptr, chunk_data->info_ptr, PNG_INFO_PLTE) != 0)
       location = what | before_IDAT;
 
    else
       location = what | before_PLTE;
 
-   if (data->location[0] == 0)
-      data->location[0] = location;
+   if (chunk_data->location[0] == 0)
+      chunk_data->location[0] = location;
 
    else
-      data->location[1] = location;
+      chunk_data->location[1] = location;
 
    return 1; /* handled */
 }
@@ -691,16 +695,16 @@
 static int PNGCBAPI
 read_user_chunk_callback(png_struct *png_ptr, png_unknown_chunkp chunk)
 {
-   struct user_chunk_data *my_user_chunk_data =
-      (struct user_chunk_data*)png_get_user_chunk_ptr(png_ptr);
+   user_chunk_info *my_user_chunk_data =
+      (user_chunk_info*)png_get_user_chunk_ptr(png_ptr);
 
    if (my_user_chunk_data == NULL)
-      png_error(png_ptr, "lost user chunk pointer");
+      png_error(png_ptr, "lost pointer to user chunk data");
 
    /* Return one of the following:
-    *    return (-n);  chunk had an error
-    *    return (0);  did not recognize
-    *    return (n);  success
+    *    return -n;  chunk had an error
+    *    return 0;   did not recognize
+    *    return n;   success
     *
     * The unknown chunk structure contains the chunk data:
     * png_byte name[5];
@@ -715,54 +719,54 @@
       {
          /* Found sTER chunk */
          if (chunk->size != 1)
-            return (-1); /* Error return */
+            return -1; /* Error return */
 
          if (chunk->data[0] != 0 && chunk->data[0] != 1)
-            return (-1);  /* Invalid mode */
+            return -1;  /* Invalid mode */
 
-         if (set_location(png_ptr, my_user_chunk_data, have_sTER) != 0)
+         if (set_chunk_location(png_ptr, my_user_chunk_data, have_sTER) != 0)
          {
-            my_user_chunk_data->sTER_mode=chunk->data[0];
-            return (1);
+            my_user_chunk_data->sTER_mode = chunk->data[0];
+            return 1;
          }
 
          else
-            return (0); /* duplicate sTER - give it to libpng */
+            return 0; /* duplicate sTER - give it to libpng */
       }
 
    if (chunk->name[0] != 118 || chunk->name[1] != 112 ||    /* v  p */
        chunk->name[2] !=  65 || chunk->name[3] != 103)      /* A  g */
-      return (0); /* Did not recognize */
+      return 0; /* Did not recognize */
 
    /* Found ImageMagick vpAg chunk */
 
    if (chunk->size != 9)
-      return (-1); /* Error return */
+      return -1; /* Error return */
 
-   if (set_location(png_ptr, my_user_chunk_data, have_vpAg) == 0)
-      return (0);  /* duplicate vpAg */
+   if (set_chunk_location(png_ptr, my_user_chunk_data, have_vpAg) == 0)
+      return 0;  /* duplicate vpAg */
 
    my_user_chunk_data->vpAg_width = png_get_uint_31(png_ptr, chunk->data);
    my_user_chunk_data->vpAg_height = png_get_uint_31(png_ptr, chunk->data + 4);
    my_user_chunk_data->vpAg_units = chunk->data[8];
 
-   return (1);
+   return 1;
 }
 
 #ifdef PNG_WRITE_SUPPORTED
 static void
-write_sTER_chunk(png_structp write_ptr)
+write_sTER_chunk(png_structp write_ptr, user_chunk_info *data)
 {
    png_byte sTER[5] = {115,  84,  69,  82, '\0'};
 
    if (verbose != 0)
-      fprintf(STDERR, "\n stereo mode = %d\n", user_chunk_data.sTER_mode);
+      fprintf(STDERR, "\n stereo mode = %d\n", data->sTER_mode);
 
-   png_write_chunk(write_ptr, sTER, &user_chunk_data.sTER_mode, 1);
+   png_write_chunk(write_ptr, sTER, &data->sTER_mode, 1);
 }
 
 static void
-write_vpAg_chunk(png_structp write_ptr)
+write_vpAg_chunk(png_structp write_ptr, user_chunk_info *data)
 {
    png_byte vpAg[5] = {118, 112,  65, 103, '\0'};
 
@@ -770,18 +774,18 @@
 
    if (verbose != 0)
       fprintf(STDERR, " vpAg = %lu x %lu, units = %d\n",
-          (unsigned long)user_chunk_data.vpAg_width,
-          (unsigned long)user_chunk_data.vpAg_height,
-          user_chunk_data.vpAg_units);
+          (unsigned long)data->vpAg_width,
+          (unsigned long)data->vpAg_height,
+          data->vpAg_units);
 
-   png_save_uint_32(vpag_chunk_data, user_chunk_data.vpAg_width);
-   png_save_uint_32(vpag_chunk_data + 4, user_chunk_data.vpAg_height);
-   vpag_chunk_data[8] = user_chunk_data.vpAg_units;
+   png_save_uint_32(vpag_chunk_data, data->vpAg_width);
+   png_save_uint_32(vpag_chunk_data + 4, data->vpAg_height);
+   vpag_chunk_data[8] = data->vpAg_units;
    png_write_chunk(write_ptr, vpAg, vpag_chunk_data, 9);
 }
 
 static void
-write_chunks(png_structp write_ptr, int location)
+write_chunks(png_structp write_ptr, user_chunk_info *data, int location)
 {
    int i;
 
@@ -791,13 +795,13 @@
     * vpAg chunks, resulting in an error later.  This is not worth worrying
     * about - the chunks should not be duplicated!
     */
-   for (i=0; i<2; ++i)
+   for (i = 0; i < 2; ++i)
    {
-      if (user_chunk_data.location[i] == (location | have_sTER))
-         write_sTER_chunk(write_ptr);
+      if (data->location[i] == (location | have_sTER))
+         write_sTER_chunk(write_ptr, data);
 
-      else if (user_chunk_data.location[i] == (location | have_vpAg))
-         write_vpAg_chunk(write_ptr);
+      else if (data->location[i] == (location | have_vpAg))
+         write_vpAg_chunk(write_ptr, data);
    }
 }
 #endif /* WRITE */
@@ -872,9 +876,9 @@
    png_bytep row_buf;
    png_uint_32 y;
    png_uint_32 width, height;
-   volatile int num_passes;
-   int pass;
    int bit_depth, color_type;
+   user_chunk_info my_user_chunk_data;
+   int pass, num_passes;
 
    row_buf = NULL;
    error_parameters.file_name = inname;
@@ -882,14 +886,14 @@
    if ((fpin = fopen(inname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find input file %s\n", inname);
-      return (1);
+      return 1;
    }
 
    if ((fpout = fopen(outname, "wb")) == NULL)
    {
       fprintf(STDERR, "Could not open output file %s\n", outname);
-      FCLOSE(fpin);
-      return (1);
+      fclose(fpin);
+      return 1;
    }
 
    pngtest_debug("Allocating read and write structures");
@@ -925,8 +929,8 @@
 #endif
 
 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
-   init_callback_info(read_info_ptr);
-   png_set_read_user_chunk_fn(read_ptr, &user_chunk_data,
+   init_user_chunk_info(read_info_ptr, &my_user_chunk_data);
+   png_set_read_user_chunk_fn(read_ptr, &my_user_chunk_data,
        read_user_chunk_callback);
 #endif
 
@@ -946,9 +950,9 @@
       png_destroy_info_struct(write_ptr, &write_end_info_ptr);
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
 #endif
-      FCLOSE(fpin);
-      FCLOSE(fpout);
-      return (1);
+      fclose(fpin);
+      fclose(fpout);
+      return 1;
    }
 
 #ifdef PNG_WRITE_SUPPORTED
@@ -966,9 +970,9 @@
         fprintf(STDERR, "   destroying write structs\n");
       png_destroy_info_struct(write_ptr, &write_end_info_ptr);
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
-      FCLOSE(fpin);
-      FCLOSE(fpout);
-      return (1);
+      fclose(fpin);
+      fclose(fpout);
+      return 1;
    }
 #endif
 #endif
@@ -1053,13 +1057,13 @@
 #endif
 
 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
-   /* Preserve all the unknown chunks, if possible.  If this is disabled then,
+   /* Preserve all the unknown chunks, if possible.  If this is disabled, then
     * even if the png_{get,set}_unknown_chunks stuff is enabled, we can't use
     * libpng to *save* the unknown chunks on read (because we can't switch the
     * save option on!)
     *
-    * Notice that if SET_UNKNOWN_CHUNKS is *not* supported read will discard all
-    * unknown chunks and write will write them all.
+    * Notice that if SET_UNKNOWN_CHUNKS is *not* supported, the reader will
+    * discard all unknown chunks, and the writer will write them all.
     */
 #ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
    png_set_keep_unknown_chunks(read_ptr, PNG_HANDLE_CHUNK_ALWAYS,
@@ -1080,7 +1084,7 @@
     * remove the info_ptr (which is only used to determine position relative to
     * PLTE) here to indicate that we are after the IDAT.
     */
-   user_chunk_data.info_ptr = NULL;
+   my_user_chunk_data.info_ptr = NULL;
 #endif
 
    pngtest_debug("Transferring info struct");
@@ -1196,14 +1200,12 @@
       png_color_16p background;
 
       if (png_get_bKGD(read_ptr, read_info_ptr, &background) != 0)
-      {
          png_set_bKGD(write_ptr, write_info_ptr, background);
-      }
    }
 #endif
 #ifdef PNG_READ_eXIf_SUPPORTED
    {
-      png_bytep exif=NULL;
+      png_bytep exif = NULL;
       png_uint_32 exif_length;
 
       if (png_get_eXIf_1(read_ptr, read_info_ptr, &exif_length, &exif) != 0)
@@ -1232,9 +1234,7 @@
 
       if (png_get_oFFs(read_ptr, read_info_ptr, &offset_x, &offset_y,
           &unit_type) != 0)
-      {
          png_set_oFFs(write_ptr, write_info_ptr, offset_x, offset_y, unit_type);
-      }
    }
 #endif
 #ifdef PNG_pCAL_SUPPORTED
@@ -1246,10 +1246,8 @@
 
       if (png_get_pCAL(read_ptr, read_info_ptr, &purpose, &X0, &X1, &type,
           &nparams, &units, &params) != 0)
-      {
          png_set_pCAL(write_ptr, write_info_ptr, purpose, X0, X1, type,
              nparams, units, params);
-      }
    }
 #endif
 #ifdef PNG_pHYs_SUPPORTED
@@ -1279,9 +1277,7 @@
 
       if (png_get_sCAL(read_ptr, read_info_ptr, &unit, &scal_width,
           &scal_height) != 0)
-      {
          png_set_sCAL(write_ptr, write_info_ptr, unit, scal_width, scal_height);
-      }
    }
 #else
 #ifdef PNG_FIXED_POINT_SUPPORTED
@@ -1304,11 +1300,9 @@
    {
        png_sPLT_tp entries;
 
-       int num_entries = (int) png_get_sPLT(read_ptr, read_info_ptr, &entries);
-       if (num_entries)
-       {
+       int num_entries = png_get_sPLT(read_ptr, read_info_ptr, &entries);
+       if (num_entries != 0)
            png_set_sPLT(write_ptr, write_info_ptr, entries, num_entries);
-       }
    }
 #endif
 
@@ -1328,7 +1322,7 @@
             int i;
 
             fprintf(STDERR,"\n");
-            for (i=0; i<num_text; i++)
+            for (i = 0; i < num_text; i++)
             {
                fprintf(STDERR,"   Text compression[%d]=%d\n",
                    i, text_ptr[i].compression);
@@ -1390,22 +1384,8 @@
           &unknowns);
 
       if (num_unknowns != 0)
-      {
          png_set_unknown_chunks(write_ptr, write_info_ptr, unknowns,
              num_unknowns);
-#if PNG_LIBPNG_VER < 10600
-         /* Copy the locations from the read_info_ptr.  The automatically
-          * generated locations in write_end_info_ptr are wrong prior to 1.6.0
-          * because they are reset from the write pointer (removed in 1.6.0).
-          */
-         {
-            int i;
-            for (i = 0; i < num_unknowns; i++)
-              png_set_unknown_chunk_location(write_ptr, write_info_ptr, i,
-                  unknowns[i].location);
-         }
-#endif
-      }
    }
 #endif
 
@@ -1417,15 +1397,15 @@
     */
    png_write_info_before_PLTE(write_ptr, write_info_ptr);
 
-   write_chunks(write_ptr, before_PLTE); /* before PLTE */
+   write_chunks(write_ptr, &my_user_chunk_data, before_PLTE); /* before PLTE */
 
    png_write_info(write_ptr, write_info_ptr);
 
-   write_chunks(write_ptr, before_IDAT); /* after PLTE */
+   write_chunks(write_ptr, &my_user_chunk_data, before_IDAT); /* after PLTE */
 
    png_write_info(write_ptr, write_end_info_ptr);
 
-   write_chunks(write_ptr, after_IDAT); /* after IDAT */
+   write_chunks(write_ptr, &my_user_chunk_data, after_IDAT); /* after IDAT */
 
 #ifdef PNG_COMPRESSION_COMPAT
    /* Test the 'compatibility' setting here, if it is available. */
@@ -1433,13 +1413,6 @@
 #endif
 #endif
 
-#ifdef SINGLE_ROWBUF_ALLOC
-   pngtest_debug("Allocating row buffer...");
-   row_buf = (png_bytep)png_malloc(read_ptr,
-       png_get_rowbytes(read_ptr, read_info_ptr));
-
-   pngtest_debug1("\t%p", row_buf);
-#endif /* SINGLE_ROWBUF_ALLOC */
    pngtest_debug("Writing row data");
 
 #if defined(PNG_READ_INTERLACING_SUPPORTED) &&\
@@ -1486,7 +1459,6 @@
       pngtest_debug1("Writing row data for pass %d", pass);
       for (y = 0; y < pass_height; y++)
       {
-#ifndef SINGLE_ROWBUF_ALLOC
          pngtest_debug2("Allocating row buffer (pass %d, y = %u)...", pass, y);
 
          row_buf = (png_bytep)png_malloc(read_ptr,
@@ -1495,7 +1467,6 @@
          pngtest_debug2("\t%p (%lu bytes)", row_buf,
              (unsigned long)png_get_rowbytes(read_ptr, read_info_ptr));
 
-#endif /* !SINGLE_ROWBUF_ALLOC */
          png_read_rows(read_ptr, (png_bytepp)&row_buf, NULL, 1);
 
 #ifdef PNG_WRITE_SUPPORTED
@@ -1512,11 +1483,9 @@
 #endif
 #endif /* WRITE */
 
-#ifndef SINGLE_ROWBUF_ALLOC
          pngtest_debug2("Freeing row buffer (pass %d, y = %u)", pass, y);
          png_free(read_ptr, row_buf);
          row_buf = NULL;
-#endif /* !SINGLE_ROWBUF_ALLOC */
       }
    }
 
@@ -1548,7 +1517,7 @@
             int i;
 
             fprintf(STDERR,"\n");
-            for (i=0; i<num_text; i++)
+            for (i = 0; i < num_text; i++)
             {
                fprintf(STDERR,"   Text compression[%d]=%d\n",
                    i, text_ptr[i].compression);
@@ -1561,7 +1530,7 @@
 #endif
 #ifdef PNG_READ_eXIf_SUPPORTED
    {
-      png_bytep exif=NULL;
+      png_bytep exif = NULL;
       png_uint_32 exif_length;
 
       if (png_get_eXIf_1(read_ptr, end_info_ptr, &exif_length, &exif) != 0)
@@ -1604,22 +1573,8 @@
           &unknowns);
 
       if (num_unknowns != 0)
-      {
          png_set_unknown_chunks(write_ptr, write_end_info_ptr, unknowns,
              num_unknowns);
-#if PNG_LIBPNG_VER < 10600
-         /* Copy the locations from the read_info_ptr.  The automatically
-          * generated locations in write_end_info_ptr are wrong prior to 1.6.0
-          * because they are reset from the write pointer (removed in 1.6.0).
-          */
-         {
-            int i;
-            for (i = 0; i < num_unknowns; i++)
-              png_set_unknown_chunk_location(write_ptr, write_end_info_ptr, i,
-                  unknowns[i].location);
-         }
-#endif
-      }
    }
 #endif
 
@@ -1638,7 +1593,7 @@
     * There seems to be no way round this, however vpAg/sTER are not expected
     * after IDAT.
     */
-   write_chunks(write_ptr, after_IDAT);
+   write_chunks(write_ptr, &my_user_chunk_data, after_IDAT);
 
    png_write_end(write_ptr, write_end_info_ptr);
 #endif
@@ -1655,23 +1610,18 @@
 #endif
 
    pngtest_debug("Destroying data structs");
-#ifdef SINGLE_ROWBUF_ALLOC
-   pngtest_debug("destroying row_buf for read_ptr");
-   png_free(read_ptr, row_buf);
-   row_buf = NULL;
-#endif /* SINGLE_ROWBUF_ALLOC */
-   pngtest_debug("destroying read_ptr, read_info_ptr, end_info_ptr");
+   pngtest_debug("Destroying read_ptr, read_info_ptr, end_info_ptr");
    png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
 #ifdef PNG_WRITE_SUPPORTED
-   pngtest_debug("destroying write_end_info_ptr");
+   pngtest_debug("Destroying write_end_info_ptr");
    png_destroy_info_struct(write_ptr, &write_end_info_ptr);
-   pngtest_debug("destroying write_ptr, write_info_ptr");
+   pngtest_debug("Destroying write_ptr, write_info_ptr");
    png_destroy_write_struct(&write_ptr, &write_info_ptr);
 #endif
    pngtest_debug("Destruction complete.");
 
-   FCLOSE(fpin);
-   FCLOSE(fpout);
+   fclose(fpin);
+   fclose(fpout);
 
    /* Summarize any warnings or errors and in 'strict' mode fail the test.
     * Unsupported chunks can result in warnings, in that case ignore the strict
@@ -1686,7 +1636,7 @@
           inname, error_count, warning_count);
 
       if (strict != 0)
-         return (1);
+         return 1;
    }
 
 #  ifdef PNG_WRITE_SUPPORTED
@@ -1704,21 +1654,21 @@
           inname, warning_count);
 
       if (strict != 0)
-         return (1);
+         return 1;
    }
 
    pngtest_debug("Opening files for comparison");
    if ((fpin = fopen(inname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find file %s\n", inname);
-      return (1);
+      return 1;
    }
 
    if ((fpout = fopen(outname, "rb")) == NULL)
    {
       fprintf(STDERR, "Could not find file %s\n", outname);
-      FCLOSE(fpin);
-      return (1);
+      fclose(fpin);
+      return 1;
    }
 
 #if defined (PNG_WRITE_SUPPORTED) /* else nothing was written */ &&\
@@ -1753,14 +1703,14 @@
                wrote_question = 1;
             }
 
-            FCLOSE(fpin);
-            FCLOSE(fpout);
+            fclose(fpin);
+            fclose(fpout);
 
             if (strict != 0 && unsupported_chunks == 0)
-              return (1);
+              return 1;
 
             else
-              return (0);
+              return 0;
          }
 
          if (num_in == 0)
@@ -1785,8 +1735,8 @@
                wrote_question = 1;
             }
 
-            FCLOSE(fpin);
-            FCLOSE(fpout);
+            fclose(fpin);
+            fclose(fpout);
 
             /* NOTE: the unsupported_chunks escape is permitted here because
              * unsupported text chunk compression will result in the compression
@@ -1794,19 +1744,19 @@
              * can be exactly the same size!
              */
             if (strict != 0 && unsupported_chunks == 0)
-              return (1);
+              return 1;
 
             else
-              return (0);
+              return 0;
          }
       }
    }
 #endif /* WRITE && WRITE_FILTER */
 
-   FCLOSE(fpin);
-   FCLOSE(fpout);
+   fclose(fpin);
+   fclose(fpout);
 
-   return (0);
+   return 0;
 }
 
 /* Input and output filenames */
@@ -1851,12 +1801,11 @@
       fprintf(STDERR, " NOTE: libpng compiled for max 64k, zlib not\n");
 #endif
 
-   if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING))
+   if (strcmp(png_libpng_ver, PNG_LIBPNG_VER_STRING) != 0)
    {
-      fprintf(STDERR,
-          "Warning: versions are different between png.h and png.c\n");
-      fprintf(STDERR, "  png.h version: %s\n", PNG_LIBPNG_VER_STRING);
-      fprintf(STDERR, "  png.c version: %s\n\n", png_libpng_ver);
+      fprintf(STDERR, "Warning: mismatching versions of png.h and png.c\n");
+      fprintf(STDERR, "  png.h version string: %s\n", PNG_LIBPNG_VER_STRING);
+      fprintf(STDERR, "  png.c version string: %s\n\n", png_libpng_ver);
       ++ierror;
    }
 
@@ -1890,7 +1839,7 @@
          inname = argv[2];
          strict++;
          relaxed = 0;
-         multiple=1;
+         multiple = 1;
       }
 
       else if (strcmp(argv[1], "--relaxed") == 0)
@@ -1900,7 +1849,7 @@
          inname = argv[2];
          strict = 0;
          relaxed++;
-         multiple=1;
+         multiple = 1;
       }
       else if (strcmp(argv[1], "--xfail") == 0)
       {
@@ -1910,7 +1859,7 @@
          strict = 0;
          xfail++;
          relaxed++;
-         multiple=1;
+         multiple = 1;
       }
 
       else
@@ -1942,7 +1891,7 @@
 #if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
       int allocation_now = current_allocation;
 #endif
-      for (i=2; i<argc; ++i)
+      for (i = 2; i < argc; ++i)
       {
          int kerror;
          fprintf(STDERR, "\n Testing %s:", argv[i]);
@@ -2013,7 +1962,7 @@
    else
    {
       int i;
-      for (i = 0; i<3; ++i)
+      for (i = 0; i < 3; ++i)
       {
          int kerror;
 #if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
@@ -2141,7 +2090,7 @@
           (unsigned long) png_get_chunk_malloc_max(dummy_ptr));
    png_destroy_read_struct(&dummy_ptr, NULL, NULL);
 
-   return (int)(ierror != 0);
+   return (ierror != 0);
 }
 #else
 int
@@ -2150,9 +2099,6 @@
    fprintf(STDERR,
        " test ignored because libpng was not built with read support\n");
    /* And skip this test */
-   return PNG_LIBPNG_VER < 10600 ? 0 : 77;
+   return SKIP;
 }
 #endif
-
-/* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_38_git Your_png_h_is_not_version_1_6_38_git;
diff --git a/pngtrans.c b/pngtrans.c
index 1100f46..62cb21e 100644
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -103,10 +103,10 @@
    if (png_ptr != 0 && png_ptr->interlaced != 0)
    {
       png_ptr->transformations |= PNG_INTERLACE;
-      return (7);
+      return 7;
    }
 
-   return (1);
+   return 1;
 }
 #endif
 
@@ -498,6 +498,8 @@
    png_bytep dp = row; /* destination pointer */
    png_bytep ep = row + row_info->rowbytes; /* One beyond end of row */
 
+   png_debug(1, "in png_do_strip_channel");
+
    /* At the start sp will point to the first byte to copy and dp to where
     * it is copied to.  ep always points just beyond the end of the row, so
     * the loop simply copies (channels-1) channels until sp reaches ep.
@@ -698,6 +700,8 @@
 void /* PRIVATE */
 png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
 {
+   png_debug(1, "in png_do_check_palette_indexes");
+
    if (png_ptr->num_palette < (1 << row_info->bit_depth) &&
       png_ptr->num_palette > 0) /* num_palette can be 0 in MNG files */
    {
@@ -708,7 +712,7 @@
        * forms produced on either GCC or MSVC.
        */
       int padding = PNG_PADBITS(row_info->pixel_depth, row_info->width);
-      png_bytep rp = png_ptr->row_buf + row_info->rowbytes - 1;
+      png_bytep rp = png_ptr->row_buf + row_info->rowbytes;
 
       switch (row_info->bit_depth)
       {
@@ -833,7 +837,7 @@
 png_get_user_transform_ptr(png_const_structrp png_ptr)
 {
    if (png_ptr == NULL)
-      return (NULL);
+      return NULL;
 
    return png_ptr->user_transform_ptr;
 }
diff --git a/pngwrite.c b/pngwrite.c
index 59377a4..77e412f 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1,7 +1,7 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * Copyright (c) 2018-2019 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -75,10 +75,10 @@
  * library.  If you have a new chunk to add, make a function to write it,
  * and put it in the correct location here.  If you want the chunk written
  * after the image data, put it in png_write_end().  I strongly encourage
- * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
- * the chunk, as that will keep the code from breaking if you want to just
- * write a plain PNG file.  If you have long comments, I suggest writing
- * them in png_write_end(), and compressing them.
+ * you to supply a PNG_INFO_<chunk> flag, and check info_ptr->valid before
+ * writing the chunk, as that will keep the code from breaking if you want
+ * to just write a plain PNG file.  If you have long comments, I suggest
+ * writing them in png_write_end(), and compressing them.
  */
 void PNGAPI
 png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
@@ -239,7 +239,10 @@
 
 #ifdef PNG_WRITE_eXIf_SUPPORTED
    if ((info_ptr->valid & PNG_INFO_eXIf) != 0)
+   {
       png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif);
+      png_ptr->mode |= PNG_WROTE_eXIf;
+   }
 #endif
 
 #ifdef PNG_WRITE_hIST_SUPPORTED
@@ -366,7 +369,8 @@
       png_error(png_ptr, "No IDATs written into file");
 
 #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
-   if (png_ptr->num_palette_max > png_ptr->num_palette)
+   if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
+       png_ptr->num_palette_max >= png_ptr->num_palette)
       png_benign_error(png_ptr, "Wrote palette index exceeding num_palette");
 #endif
 
@@ -439,8 +443,9 @@
 #endif
 
 #ifdef PNG_WRITE_eXIf_SUPPORTED
-   if ((info_ptr->valid & PNG_INFO_eXIf) != 0)
-      png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif);
+      if ((info_ptr->valid & PNG_INFO_eXIf) != 0 &&
+          (png_ptr->mode & PNG_WROTE_eXIf) == 0)
+         png_write_eXIf(png_ptr, info_ptr->exif, info_ptr->num_exif);
 #endif
 
 #ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
@@ -489,6 +494,16 @@
    png_debug(1, "in png_convert_from_time_t");
 
    tbuf = gmtime(&ttime);
+   if (tbuf == NULL)
+   {
+      /* TODO: add a safe function which takes a png_ptr argument and raises
+       * a png_error if the ttime argument is invalid and the call to gmtime
+       * fails as a consequence.
+       */
+      memset(ptime, 0, sizeof(*ptime));
+      return;
+   }
+
    png_convert_from_struct_tm(ptime, tbuf);
 }
 #endif
@@ -700,12 +715,12 @@
    /* 1.5.6: moved from png_struct to be a local structure: */
    png_row_info row_info;
 
-   if (png_ptr == NULL)
-      return;
-
    png_debug2(1, "in png_write_row (row %u, pass %d)",
        png_ptr->row_number, png_ptr->pass);
 
+   if (png_ptr == NULL)
+      return;
+
    /* Initialize transformations and other stuff if first time */
    if (png_ptr->row_number == 0 && png_ptr->pass == 0)
    {
@@ -1196,6 +1211,8 @@
 void PNGAPI
 png_set_compression_window_bits(png_structrp png_ptr, int window_bits)
 {
+   png_debug(1, "in png_set_compression_window_bits");
+
    if (png_ptr == NULL)
       return;
 
@@ -1279,6 +1296,8 @@
 void PNGAPI
 png_set_text_compression_window_bits(png_structrp png_ptr, int window_bits)
 {
+   png_debug(1, "in png_set_text_compression_window_bits");
+
    if (png_ptr == NULL)
       return;
 
@@ -1316,6 +1335,8 @@
 void PNGAPI
 png_set_write_status_fn(png_structrp png_ptr, png_write_status_ptr write_row_fn)
 {
+   png_debug(1, "in png_set_write_status_fn");
+
    if (png_ptr == NULL)
       return;
 
@@ -1343,6 +1364,8 @@
 png_write_png(png_structrp png_ptr, png_inforp info_ptr,
     int transforms, voidp params)
 {
+   png_debug(1, "in png_write_png");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
diff --git a/pngwutil.c b/pngwutil.c
index 16345e4..14cc4ce 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -1,7 +1,7 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * Copyright (c) 2018 Cosmin Truta
+ * Copyright (c) 2018-2024 Cosmin Truta
  * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
  * Copyright (c) 1996-1997 Andreas Dilger
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
@@ -1747,7 +1747,7 @@
 {
    png_uint_32 purpose_len;
    size_t units_len, total_len;
-   png_size_tp params_len;
+   size_t *params_len;
    png_byte buf[10];
    png_byte new_purpose[80];
    int i;
@@ -1769,7 +1769,7 @@
    png_debug1(3, "pCAL units length = %d", (int)units_len);
    total_len = purpose_len + units_len + 10;
 
-   params_len = (png_size_tp)png_malloc(png_ptr,
+   params_len = (size_t *)png_malloc(png_ptr,
        (png_alloc_size_t)((png_alloc_size_t)nparams * (sizeof (size_t))));
 
    /* Find the length of each parameter, making sure we don't count the
@@ -2311,7 +2311,7 @@
         break;
    }
 
-   return (sum);
+   return sum;
 }
 
 static void /* PRIVATE */
@@ -2361,7 +2361,7 @@
         break;
    }
 
-   return (sum);
+   return sum;
 }
 static void /* PRIVATE */
 png_setup_up_row_only(png_structrp png_ptr, size_t row_bytes)
@@ -2417,7 +2417,7 @@
         break;
    }
 
-   return (sum);
+   return sum;
 }
 static void /* PRIVATE */
 png_setup_avg_row_only(png_structrp png_ptr, png_uint_32 bpp,
@@ -2500,7 +2500,7 @@
         break;
    }
 
-   return (sum);
+   return sum;
 }
 static void /* PRIVATE */
 png_setup_paeth_row_only(png_structrp png_ptr, png_uint_32 bpp,
diff --git a/powerpc/.editorconfig b/powerpc/.editorconfig
new file mode 100644
index 0000000..b142d82
--- /dev/null
+++ b/powerpc/.editorconfig
@@ -0,0 +1,7 @@
+# https://editorconfig.org
+
+root = false
+
+# FIXME
+[*.[ch]]
+max_line_length = unset
diff --git a/projects/.editorconfig b/projects/.editorconfig
new file mode 100644
index 0000000..bd9b590
--- /dev/null
+++ b/projects/.editorconfig
@@ -0,0 +1,13 @@
+# https://editorconfig.org
+
+root = false
+
+[*]
+charset = unset
+end_of_line = unset
+indent_size = unset
+indent_style = unset
+insert_final_newline = unset
+max_doc_length = unset
+max_line_length = unset
+trim_trailing_whitespace = unset
diff --git a/projects/vstudio/README.txt b/projects/vstudio/README.txt
index e28ec95..53f6b59 100644
--- a/projects/vstudio/README.txt
+++ b/projects/vstudio/README.txt
@@ -1,7 +1,7 @@
 Instructions for building libpng using Microsoft Visual Studio
 ==============================================================
 
-Copyright (c) 2018 Cosmin Truta
+Copyright (c) 2018,2022 Cosmin Truta
 Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
 
 This code is released under the libpng license.
@@ -9,9 +9,9 @@
 in png.h
 
 This directory contains a solution for building libpng under Microsoft
-Visual Studio 2010.  It may also work under later versions of Visual
-Studio.  You should be familiar with Visual Studio before using this
-solution.
+Visual Studio 2019.  It may also work under earlier or later versions
+of Visual Studio.  You should be familiar with Visual Studio before
+using this solution.
 
 Initial preparations
 --------------------
diff --git a/projects/vstudio/libpng/libpng.vcxproj b/projects/vstudio/libpng/libpng.vcxproj
index 9bfb718..e10f4ff 100644
--- a/projects/vstudio/libpng/libpng.vcxproj
+++ b/projects/vstudio/libpng/libpng.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -29,19 +45,45 @@
     <ConfigurationType>DynamicLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
     <WholeProgramOptimization>true</WholeProgramOptimization>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>DynamicLibrary</ConfigurationType>
     <WholeProgramOptimization>true</WholeProgramOptimization>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>DynamicLibrary</ConfigurationType>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -49,15 +91,27 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
@@ -65,22 +119,42 @@
     </CustomBuildBeforeTargets>
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets>
     </CustomBuildBeforeTargets>
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildBeforeTargets />
     <TargetName>$(ProjectName)16</TargetName>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildBeforeTargets />
+    <TargetName>$(ProjectName)16</TargetName>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
@@ -88,7 +162,37 @@
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <Optimization>Disabled</Optimization>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>zlib.lib</AdditionalDependencies>
+      <Version>16</Version>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <FloatingPointExceptions>false</FloatingPointExceptions>
@@ -114,12 +218,12 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <FloatingPointExceptions>false</FloatingPointExceptions>
@@ -130,7 +234,34 @@
       <StringPooling>true</StringPooling>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -145,7 +276,37 @@
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <Optimization>Full</Optimization>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>zlib.lib</AdditionalDependencies>
+      <Version>16</Version>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_USRDLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <FloatingPointExceptions>false</FloatingPointExceptions>
       <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
       <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
@@ -170,13 +331,13 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <PrecompiledHeader>Use</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <FloatingPointExceptions>false</FloatingPointExceptions>
       <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
       <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
@@ -186,7 +347,39 @@
       <MinimalRebuild>false</MinimalRebuild>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <Optimization>Full</Optimization>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+    </ClCompile>
+    <Link>
+      <SubSystem>Windows</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>Use</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <TreatWChar_tAsBuiltInType>false</TreatWChar_tAsBuiltInType>
+      <PrecompiledHeaderFile>pngpriv.h</PrecompiledHeaderFile>
+      <BrowseInformation>true</BrowseInformation>
+      <CompileAs>CompileAsC</CompileAs>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <Optimization>Full</Optimization>
       <WholeProgramOptimization>true</WholeProgramOptimization>
     </ClCompile>
@@ -201,11 +394,40 @@
     </Lib>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClCompile Include="..\..\..\arm\arm_init.c">
+      <DeploymentContent>true</DeploymentContent>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="..\..\..\arm\filter_neon_intrinsics.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
+    <ClCompile Include="..\..\..\arm\palette_neon_intrinsics.c">
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">NotUsing</PrecompiledHeader>
+      <PreprocessorDefinitions Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">WIN32;_DEBUG;PNG_ARM_NEON_OPT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">NotUsing</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">NotUsing</PrecompiledHeader>
+    </ClCompile>
     <ClCompile Include="..\..\..\png.c">
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">Create</PrecompiledHeader>
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">Create</PrecompiledHeader>
+      <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">Create</PrecompiledHeader>
     </ClCompile>
     <ClCompile Include="..\..\..\pngerror.c" />
     <ClCompile Include="..\..\..\pngget.c" />
@@ -225,7 +447,9 @@
   <ItemGroup>
     <ResourceCompile Include="..\..\..\scripts\pngwin.rc">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">true</ExcludedFromBuild>
     </ResourceCompile>
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
diff --git a/projects/vstudio/pnglibconf/pnglibconf.vcxproj b/projects/vstudio/pnglibconf/pnglibconf.vcxproj
index efcc440..e0a3887 100644
--- a/projects/vstudio/pnglibconf/pnglibconf.vcxproj
+++ b/projects/vstudio/pnglibconf/pnglibconf.vcxproj
@@ -1,6 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -16,6 +20,14 @@
     <UseDebugLibraries>false</UseDebugLibraries>
     <WholeProgramOptimization>true</WholeProgramOptimization>
     <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(SolutionDir)\zlib.props" />
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
@@ -24,10 +36,16 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <CustomBuildBeforeTargets>Build</CustomBuildBeforeTargets>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <CustomBuildBeforeTargets>Build</CustomBuildBeforeTargets>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
@@ -53,6 +71,31 @@
       <Inputs>..\..\..\scripts\pnglibconf.h.prebuilt</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <Optimization>MaxSpeed</Optimization>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <CustomBuildStep>
+      <Command>copy ..\..\..\scripts\pnglibconf.h.prebuilt ..\..\..\pnglibconf.h</Command>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Message>Generating pnglibconf.h</Message>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Outputs>..\..\..\pnglibconf.h</Outputs>
+    </CustomBuildStep>
+    <CustomBuildStep>
+      <Inputs>..\..\..\scripts\pnglibconf.h.prebuilt</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
   <ItemGroup>
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
diff --git a/projects/vstudio/pngstest/pngstest.vcxproj b/projects/vstudio/pngstest/pngstest.vcxproj
index 21810e3..3937cb4 100644
--- a/projects/vstudio/pngstest/pngstest.vcxproj
+++ b/projects/vstudio/pngstest/pngstest.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
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     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngstest.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing libpng simplified API test program</Message>
+      <Command>"$(OutDir)pngstest.exe" --strict --log --touch "$(IntDir)pngstest.out" ../../../contrib/pngsuite/basn0g01.png ../../../contrib/pngsuite/basn0g02.png ../../../contrib/pngsuite/basn0g04.png ../../../contrib/pngsuite/basn0g08.png ../../../contrib/pngsuite/basn0g16.png ../../../contrib/pngsuite/basn2c08.png ../../../contrib/pngsuite/basn2c16.png ../../../contrib/pngsuite/basn3p01.png ../../../contrib/pngsuite/basn3p02.png ../../../contrib/pngsuite/basn3p04.png ../../../contrib/pngsuite/basn3p08.png ../../../contrib/pngsuite/basn4a08.png ../../../contrib/pngsuite/basn4a16.png ../../../contrib/pngsuite/basn6a08.png ../../../contrib/pngsuite/basn6a16.png ../../../contrib/pngsuite/ftbbn0g01.png ../../../contrib/pngsuite/ftbbn0g02.png ../../../contrib/pngsuite/ftbbn0g04.png ../../../contrib/pngsuite/ftbbn2c16.png ../../../contrib/pngsuite/ftbbn3p08.png ../../../contrib/pngsuite/ftbgn2c16.png ../../../contrib/pngsuite/ftbgn3p08.png ../../../contrib/pngsuite/ftbrn2c08.png ../../../contrib/pngsuite/ftbwn0g16.png ../../../contrib/pngsuite/ftbwn3p08.png ../../../contrib/pngsuite/ftbyn3p08.png ../../../contrib/pngsuite/ftp0n0g08.png ../../../contrib/pngsuite/ftp0n2c08.png ../../../contrib/pngsuite/ftp0n3p08.png ../../../contrib/pngsuite/ftp1n3p08.png</Command>
+      <Outputs>$(IntDir)pngstest.out</Outputs>
+      <Inputs>$(OutDir)pngstest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngtest/pngtest.vcxproj b/projects/vstudio/pngtest/pngtest.vcxproj
index f1df07d..72beced 100644
--- a/projects/vstudio/pngtest/pngtest.vcxproj
+++ b/projects/vstudio/pngtest/pngtest.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,44 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG test program</Message>
+      <Command>$(OutDir)pngtest.exe ..\..\..\pngtest.png $(IntDir)pngout.png</Command>
+      <Command>"$(OutDir)pngtest.exe" ..\..\..\pngtest.png "$(IntDir)pngout.png"</Command>
+      <Outputs>$(IntDir)pngout.png</Outputs>
+      <Inputs>..\..\..\pngtest.png;$(OutDir)pngtest.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngunknown/pngunknown.vcxproj b/projects/vstudio/pngunknown/pngunknown.vcxproj
index 409d662..f4d130d 100644
--- a/projects/vstudio/pngunknown/pngunknown.vcxproj
+++ b/projects/vstudio/pngunknown/pngunknown.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngunknown.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngunknown.exe" --strict --default --touch "$(IntDir)pngunknown.out" ../../../pngtest.png</Command>
+      <Outputs>$(IntDir)pngunknown.out</Outputs>
+      <Inputs>$(OutDir)pngunknown.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/pngvalid/pngvalid.vcxproj b/projects/vstudio/pngvalid/pngvalid.vcxproj
index c117d29..3726193 100644
--- a/projects/vstudio/pngvalid/pngvalid.vcxproj
+++ b/projects/vstudio/pngvalid/pngvalid.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -28,18 +44,42 @@
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>Application</ConfigurationType>
     <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <CharacterSet>Unicode</CharacterSet>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -47,36 +87,64 @@
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>false</LinkIncremental>
     <CustomBuildAfterTargets />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <LinkIncremental>false</LinkIncremental>
+    <CustomBuildAfterTargets />
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -85,7 +153,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +210,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -119,7 +220,40 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <StringPooling>true</StringPooling>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <BrowseInformation>true</BrowseInformation>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <ClCompile>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <WarningLevel>Level3</WarningLevel>
+      <MinimalRebuild>false</MinimalRebuild>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -174,12 +308,47 @@
       <Inputs>$(OutDir)pngvalid.exe</Inputs>
     </CustomBuildStep>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <FunctionLevelLinking>false</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -187,7 +356,43 @@
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <StringPooling>true</StringPooling>
+      <MinimalRebuild>false</MinimalRebuild>
+      <BrowseInformation>true</BrowseInformation>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <FloatingPointExceptions>false</FloatingPointExceptions>
+    </ClCompile>
+    <Link>
+      <SubSystem>Console</SubSystem>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalDependencies>libpng16.lib;zlib.lib</AdditionalDependencies>
+      <AdditionalLibraryDirectories>$(OutDir)</AdditionalLibraryDirectories>
+      <LinkTimeCodeGeneration>UseLinkTimeCodeGeneration</LinkTimeCodeGeneration>
+    </Link>
+    <CustomBuildStep>
+      <Message>Executing PNG validation program</Message>
+      <Command>"$(OutDir)pngvalid.exe" --touch "$(IntDir)pngvalid.out"</Command>
+      <Outputs>$(IntDir)pngvalid.out</Outputs>
+      <Inputs>$(OutDir)pngvalid.exe</Inputs>
+    </CustomBuildStep>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <PrecompiledHeader>NotUsing</PrecompiledHeader>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <FunctionLevelLinking>false</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
+      <CompileAsManaged>false</CompileAsManaged>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
diff --git a/projects/vstudio/vstudio.sln b/projects/vstudio/vstudio.sln
index af0b1ba..5fc1c29 100644
--- a/projects/vstudio/vstudio.sln
+++ b/projects/vstudio/vstudio.sln
@@ -1,5 +1,7 @@
-Microsoft Visual Studio Solution File, Format Version 11.00
-# Visual Studio 2010
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.31515.178
+MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "zlib", "zlib\zlib.vcxproj", "{60F89955-91C6-3A36-8000-13C592FEC2DF}"
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "pnglibconf", "pnglibconf\pnglibconf.vcxproj", "{EB33566E-DA7F-4D28-9077-88C0B7C77E35}"
@@ -40,70 +42,133 @@
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug Library|ARM64 = Debug Library|ARM64
 		Debug Library|Win32 = Debug Library|Win32
+		Debug|ARM64 = Debug|ARM64
 		Debug|Win32 = Debug|Win32
+		Release Library|ARM64 = Release Library|ARM64
 		Release Library|Win32 = Release Library|Win32
+		Release|ARM64 = Release|ARM64
 		Release|Win32 = Release|Win32
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.Build.0 = Debug Library|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.ActiveCfg = Debug|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.Build.0 = Debug|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.ActiveCfg = Release Library|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.Build.0 = Release Library|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.ActiveCfg = Release|Win32
-		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.Build.0 = Release|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.Build.0 = Debug Library|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.ActiveCfg = Debug|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.Build.0 = Debug|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.ActiveCfg = Release Library|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.Build.0 = Release Library|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.ActiveCfg = Release|Win32
-		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.Build.0 = Release|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|ARM64.Build.0 = Debug|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|Win32.ActiveCfg = Debug|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Debug|Win32.Build.0 = Debug|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release Library|Win32.Build.0 = Release Library|Win32
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|ARM64.ActiveCfg = Release|ARM64
+		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|ARM64.Build.0 = Release|ARM64
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|Win32.ActiveCfg = Release|Win32
 		{60F89955-91C6-3A36-8000-13C592FEC2DF}.Release|Win32.Build.0 = Release|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.Build.0 = Debug Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.ActiveCfg = Debug|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.Build.0 = Debug|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.ActiveCfg = Release Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.Build.0 = Release Library|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.ActiveCfg = Release|Win32
-		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug Library|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Debug|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release Library|Win32.Build.0 = Release|Win32
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|ARM64.ActiveCfg = Release|ARM64
+		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|ARM64.Build.0 = Release|ARM64
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|Win32.ActiveCfg = Release|Win32
 		{EB33566E-DA7F-4D28-9077-88C0B7C77E35}.Release|Win32.Build.0 = Release|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|ARM64.Build.0 = Debug|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.ActiveCfg = Debug|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Debug|Win32.Build.0 = Debug|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release Library|Win32.Build.0 = Release Library|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|ARM64.ActiveCfg = Release|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|ARM64.Build.0 = Release|ARM64
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.ActiveCfg = Release|Win32
+		{D6973076-9317-4EF2-A0B8-B7A18AC0713E}.Release|Win32.Build.0 = Release|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|ARM64.Build.0 = Debug|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.ActiveCfg = Debug|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Debug|Win32.Build.0 = Debug|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release Library|Win32.Build.0 = Release Library|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|ARM64.ActiveCfg = Release|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|ARM64.Build.0 = Release|ARM64
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.ActiveCfg = Release|Win32
+		{228BA965-50D5-42B2-8BCF-AFCC227E3C1D}.Release|Win32.Build.0 = Release|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|ARM64.Build.0 = Debug|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.ActiveCfg = Debug|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Debug|Win32.Build.0 = Debug|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|ARM64.Build.0 = Release Library|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.ActiveCfg = Release Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release Library|Win32.Build.0 = Release Library|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|ARM64.ActiveCfg = Release|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|ARM64.Build.0 = Release|ARM64
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.ActiveCfg = Release|Win32
+		{9B36B6FE-7FC0-434F-A71F-BBEF8099F1D8}.Release|Win32.Build.0 = Release|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|ARM64.Build.0 = Debug|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|Win32.ActiveCfg = Debug|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Debug|Win32.Build.0 = Debug|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release Library|Win32.Build.0 = Release Library|Win32
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|ARM64.ActiveCfg = Release|ARM64
+		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|ARM64.Build.0 = Release|ARM64
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|Win32.ActiveCfg = Release|Win32
 		{277AC57F-313B-4D06-B119-A3CDB672D2FF}.Release|Win32.Build.0 = Release|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|ARM64.ActiveCfg = Debug Library|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|ARM64.Build.0 = Debug Library|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|Win32.ActiveCfg = Debug Library|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug Library|Win32.Build.0 = Debug Library|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|ARM64.ActiveCfg = Debug|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|ARM64.Build.0 = Debug|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|Win32.ActiveCfg = Debug|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Debug|Win32.Build.0 = Debug|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|ARM64.ActiveCfg = Release Library|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|ARM64.Build.0 = Release Library|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|Win32.ActiveCfg = Release Library|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release Library|Win32.Build.0 = Release Library|Win32
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|ARM64.ActiveCfg = Release|ARM64
+		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|ARM64.Build.0 = Release|ARM64
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|Win32.ActiveCfg = Release|Win32
 		{C5D3156C-8C8C-4936-B35F-2B829BA36FEC}.Release|Win32.Build.0 = Release|Win32
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {785775C5-509E-4727-A290-F1B65E1B68B2}
+	EndGlobalSection
 EndGlobal
diff --git a/projects/vstudio/zlib/zlib.vcxproj b/projects/vstudio/zlib/zlib.vcxproj
index 0df16db..23e6065 100644
--- a/projects/vstudio/zlib/zlib.vcxproj
+++ b/projects/vstudio/zlib/zlib.vcxproj
@@ -1,18 +1,34 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug Library|ARM64">
+      <Configuration>Debug Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug Library|Win32">
       <Configuration>Debug Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|ARM64">
+      <Configuration>Debug</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Debug|Win32">
       <Configuration>Debug</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release Library|ARM64">
+      <Configuration>Release Library</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release Library|Win32">
       <Configuration>Release Library</Configuration>
       <Platform>Win32</Platform>
     </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|ARM64">
+      <Configuration>Release</Configuration>
+      <Platform>ARM64</Platform>
+    </ProjectConfiguration>
     <ProjectConfiguration Include="Release|Win32">
       <Configuration>Release</Configuration>
       <Platform>Win32</Platform>
@@ -40,18 +56,41 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
     <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="Configuration">
+    <ConfigurationType>StaticLibrary</ConfigurationType>
+    <PlatformToolset>v142</PlatformToolset>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">
@@ -59,42 +98,69 @@
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" />
+  </ImportGroup>
   <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="PropertySheets">
     <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
   </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <LinkIncremental>true</LinkIncremental>
+  </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -102,16 +168,33 @@
       <SubSystem>Windows</SubSystem>
     </Link>
   </ItemDefinitionGroup>
-  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|ARM64'">
     <ClCompile>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <ClCompile>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -120,9 +203,26 @@
       <SubSystem>Windows</SubSystem>
     </Link>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64'">
+    <ClCompile>
+      <PreprocessorDefinitions>WIN32;_DEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Disabled</Optimization>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -131,9 +231,9 @@
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
-      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -144,6 +244,29 @@
       <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
     </Lib>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|ARM64'">
+    <ClCompile>
+      <WarningLevel>Level3</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>false</TreatWarningAsError>
+      <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
       <WarningLevel>$(WarningLevel)</WarningLevel>
@@ -156,7 +279,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
       <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -169,6 +292,30 @@
       <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
     </Lib>
   </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64'">
+    <ClCompile>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
+      <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <Optimization>Full</Optimization>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <WholeProgramOptimization>true</WholeProgramOptimization>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <BrowseInformation>true</BrowseInformation>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
+      <PreprocessorDefinitions>WIN32;NDEBUG;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <SubSystem>Windows</SubSystem>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+    </Link>
+    <Lib>
+      <LinkTimeCodeGeneration>true</LinkTimeCodeGeneration>
+    </Lib>
+  </ItemDefinitionGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
diff --git a/scripts/README.txt b/scripts/README.txt
index 3d911ef..326160c 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -13,7 +13,7 @@
  makefile.atari    =>  Atari makefile
  makefile.bc32     =>  32-bit Borland C++ (all modules compiled in C mode)
  makefile.beos     =>  BeOS makefile
- makefile.cegcc    =>  minge32ce for Windows CE makefile
+ makefile.clang    =>  Generic clang makefile
  makefile.darwin   =>  Darwin makefile, for macOS (formerly Mac OS X)
  makefile.dec      =>  DEC Alpha UNIX makefile
  makefile.dj2      =>  DJGPP 2 makefile
@@ -75,5 +75,5 @@
  macro.lst         =>  Used by autoconf tools
  prefix.dfn        =>  Used by autoconf tools
 
-
-Further information can be found in comments in the individual makefiles.
+Further information can be found in comments in the individual scripts and
+makefiles.
diff --git a/scripts/autoconf/README.md b/scripts/autoconf/README.md
new file mode 100644
index 0000000..64963b7
--- /dev/null
+++ b/scripts/autoconf/README.md
@@ -0,0 +1,7 @@
+Autoconf Macro Files for the PNG Reference Library
+==================================================
+
+The Autoconf files associated with libpng are free software.
+Use, modification and distribution of each individual file
+are subject to the specific licensing terms and conditions
+stated at the top of the file.
diff --git a/scripts/libtool.m4 b/scripts/autoconf/libtool.m4
similarity index 97%
rename from scripts/libtool.m4
rename to scripts/autoconf/libtool.m4
index a3bc337..79a2451 100644
--- a/scripts/libtool.m4
+++ b/scripts/autoconf/libtool.m4
@@ -1,6 +1,7 @@
 # libtool.m4 - Configure libtool for the host system. -*-Autoconf-*-
 #
-#   Copyright (C) 1996-2001, 2003-2015 Free Software Foundation, Inc.
+#   Copyright (C) 1996-2001, 2003-2019, 2021-2022 Free Software
+#   Foundation, Inc.
 #   Written by Gordon Matzigkeit, 1996
 #
 # This file is free software; the Free Software Foundation gives
@@ -31,7 +32,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ])
 
-# serial 58 LT_INIT
+# serial 59 LT_INIT
 
 
 # LT_PREREQ(VERSION)
@@ -181,6 +182,7 @@
 m4_require([_LT_CHECK_SHELL_FEATURES])dnl
 m4_require([_LT_PATH_CONVERSION_FUNCTIONS])dnl
 m4_require([_LT_CMD_RELOAD])dnl
+m4_require([_LT_DECL_FILECMD])dnl
 m4_require([_LT_CHECK_MAGIC_METHOD])dnl
 m4_require([_LT_CHECK_SHAREDLIB_FROM_LINKLIB])dnl
 m4_require([_LT_CMD_OLD_ARCHIVE])dnl
@@ -219,8 +221,8 @@
 ofile=libtool
 can_build_shared=yes
 
-# All known linkers require a '.a' archive for static linking (except MSVC,
-# which needs '.lib').
+# All known linkers require a '.a' archive for static linking (except MSVC and
+# ICC, which need '.lib').
 libext=a
 
 with_gnu_ld=$lt_cv_prog_gnu_ld
@@ -778,7 +780,7 @@
   # if finds mixed CR/LF and LF-only lines.  Since sed operates in
   # text mode, it properly converts lines to CR/LF.  This bash problem
   # is reportedly fixed, but why not run on old versions too?
-  sed '$q' "$ltmain" >> "$cfgfile" \
+  $SED '$q' "$ltmain" >> "$cfgfile" \
      || (rm -f "$cfgfile"; exit 1)
 
    mv -f "$cfgfile" "$ofile" ||
@@ -1042,8 +1044,8 @@
 _LT_EOF
       echo "$LTCC $LTCFLAGS -c -o conftest.o conftest.c" >&AS_MESSAGE_LOG_FD
       $LTCC $LTCFLAGS -c -o conftest.o conftest.c 2>&AS_MESSAGE_LOG_FD
-      echo "$AR cru libconftest.a conftest.o" >&AS_MESSAGE_LOG_FD
-      $AR cru libconftest.a conftest.o 2>&AS_MESSAGE_LOG_FD
+      echo "$AR $AR_FLAGS libconftest.a conftest.o" >&AS_MESSAGE_LOG_FD
+      $AR $AR_FLAGS libconftest.a conftest.o 2>&AS_MESSAGE_LOG_FD
       echo "$RANLIB libconftest.a" >&AS_MESSAGE_LOG_FD
       $RANLIB libconftest.a 2>&AS_MESSAGE_LOG_FD
       cat > conftest.c << _LT_EOF
@@ -1067,17 +1069,12 @@
       _lt_dar_allow_undefined='$wl-undefined ${wl}suppress' ;;
     darwin1.*)
       _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-    darwin*) # darwin 5.x on
-      # if running on 10.5 or later, the deployment target defaults
-      # to the OS version, if on x86, and 10.4, the deployment
-      # target defaults to 10.4. Don't you love it?
-      case ${MACOSX_DEPLOYMENT_TARGET-10.0},$host in
-	10.0,*86*-darwin8*|10.0,*-darwin[[91]]*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
-	10.[[012]][[,.]]*)
-	  _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
-	10.*)
-	  _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
+    darwin*)
+      case $MACOSX_DEPLOYMENT_TARGET,$host in
+        10.[[012]],*|,*powerpc*-darwin[[5-8]]*)
+          _lt_dar_allow_undefined='$wl-flat_namespace $wl-undefined ${wl}suppress' ;;
+        *)
+          _lt_dar_allow_undefined='$wl-undefined ${wl}dynamic_lookup' ;;
       esac
     ;;
   esac
@@ -1126,12 +1123,12 @@
     output_verbose_link_cmd=func_echo_all
     _LT_TAGVAR(archive_cmds, $1)="\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dsymutil"
     _LT_TAGVAR(module_cmds, $1)="\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dsymutil"
-    _LT_TAGVAR(archive_expsym_cmds, $1)="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
-    _LT_TAGVAR(module_expsym_cmds, $1)="sed -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
+    _LT_TAGVAR(archive_expsym_cmds, $1)="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$libobjs \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring $_lt_dar_single_mod$_lt_dar_export_syms$_lt_dsymutil"
+    _LT_TAGVAR(module_expsym_cmds, $1)="$SED -e 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC \$allow_undefined_flag -o \$lib -bundle \$libobjs \$deplibs \$compiler_flags$_lt_dar_export_syms$_lt_dsymutil"
     m4_if([$1], [CXX],
 [   if test yes != "$lt_cv_apple_cc_single_mod"; then
       _LT_TAGVAR(archive_cmds, $1)="\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dsymutil"
-      _LT_TAGVAR(archive_expsym_cmds, $1)="sed 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dar_export_syms$_lt_dsymutil"
+      _LT_TAGVAR(archive_expsym_cmds, $1)="$SED 's|^|_|' < \$export_symbols > \$output_objdir/\$libname-symbols.expsym~\$CC -r -keep_private_externs -nostdlib -o \$lib-master.o \$libobjs~\$CC -dynamiclib \$allow_undefined_flag -o \$lib \$lib-master.o \$deplibs \$compiler_flags -install_name \$rpath/\$soname \$verstring$_lt_dar_export_syms$_lt_dsymutil"
     fi
 ],[])
   else
@@ -1245,7 +1242,8 @@
 # _LT_WITH_SYSROOT
 # ----------------
 AC_DEFUN([_LT_WITH_SYSROOT],
-[AC_MSG_CHECKING([for sysroot])
+[m4_require([_LT_DECL_SED])dnl
+AC_MSG_CHECKING([for sysroot])
 AC_ARG_WITH([sysroot],
 [AS_HELP_STRING([--with-sysroot@<:@=DIR@:>@],
   [Search for dependent libraries within DIR (or the compiler's sysroot
@@ -1262,7 +1260,7 @@
    fi
    ;; #(
  /*)
-   lt_sysroot=`echo "$with_sysroot" | sed -e "$sed_quote_subst"`
+   lt_sysroot=`echo "$with_sysroot" | $SED -e "$sed_quote_subst"`
    ;; #(
  no|'')
    ;; #(
@@ -1292,7 +1290,7 @@
   # options accordingly.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *ELF-32*)
 	HPUX_IA64_MODE=32
 	;;
@@ -1309,7 +1307,7 @@
   echo '[#]line '$LINENO' "configure"' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
     if test yes = "$lt_cv_prog_gnu_ld"; then
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -melf32bsmip"
 	  ;;
@@ -1321,7 +1319,7 @@
 	;;
       esac
     else
-      case `/usr/bin/file conftest.$ac_objext` in
+      case `$FILECMD conftest.$ac_objext` in
 	*32-bit*)
 	  LD="${LD-ld} -32"
 	  ;;
@@ -1343,7 +1341,7 @@
   echo '[#]line '$LINENO' "configure"' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
     emul=elf
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *32-bit*)
 	emul="${emul}32"
 	;;
@@ -1351,7 +1349,7 @@
 	emul="${emul}64"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *MSB*)
 	emul="${emul}btsmip"
 	;;
@@ -1359,7 +1357,7 @@
 	emul="${emul}ltsmip"
 	;;
     esac
-    case `/usr/bin/file conftest.$ac_objext` in
+    case `$FILECMD conftest.$ac_objext` in
       *N32*)
 	emul="${emul}n32"
 	;;
@@ -1379,14 +1377,14 @@
   # not appear in the list.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
       *32-bit*)
 	case $host in
 	  x86_64-*kfreebsd*-gnu)
 	    LD="${LD-ld} -m elf_i386_fbsd"
 	    ;;
 	  x86_64-*linux*)
-	    case `/usr/bin/file conftest.o` in
+	    case `$FILECMD conftest.o` in
 	      *x86-64*)
 		LD="${LD-ld} -m elf32_x86_64"
 		;;
@@ -1454,7 +1452,7 @@
   # options accordingly.
   echo 'int i;' > conftest.$ac_ext
   if AC_TRY_EVAL(ac_compile); then
-    case `/usr/bin/file conftest.o` in
+    case `$FILECMD conftest.o` in
     *64-bit*)
       case $lt_cv_prog_gnu_ld in
       yes*)
@@ -1493,9 +1491,22 @@
 m4_defun([_LT_PROG_AR],
 [AC_CHECK_TOOLS(AR, [ar], false)
 : ${AR=ar}
-: ${AR_FLAGS=cru}
 _LT_DECL([], [AR], [1], [The archiver])
-_LT_DECL([], [AR_FLAGS], [1], [Flags to create an archive])
+
+# Use ARFLAGS variable as AR's operation code to sync the variable naming with
+# Automake.  If both AR_FLAGS and ARFLAGS are specified, AR_FLAGS should have
+# higher priority because thats what people were doing historically (setting
+# ARFLAGS for automake and AR_FLAGS for libtool).  FIXME: Make the AR_FLAGS
+# variable obsoleted/removed.
+
+test ${AR_FLAGS+y} || AR_FLAGS=${ARFLAGS-cr}
+lt_ar_flags=$AR_FLAGS
+_LT_DECL([], [lt_ar_flags], [0], [Flags to create an archive (by configure)])
+
+# Make AR_FLAGS overridable by 'make ARFLAGS='.  Don't try to run-time override
+# by AR_FLAGS because that was never working and AR_FLAGS is about to die.
+_LT_DECL([], [AR_FLAGS], [\@S|@{ARFLAGS-"\@S|@lt_ar_flags"}],
+         [Flags to create an archive])
 
 AC_CACHE_CHECK([for archiver @FILE support], [lt_cv_ar_at_file],
   [lt_cv_ar_at_file=no
@@ -1714,7 +1725,7 @@
     lt_cv_sys_max_cmd_len=8192;
     ;;
 
-  bitrig* | darwin* | dragonfly* | freebsd* | netbsd* | openbsd*)
+  bitrig* | darwin* | dragonfly* | freebsd* | midnightbsd* | netbsd* | openbsd*)
     # This has been around since 386BSD, at least.  Likely further.
     if test -x /sbin/sysctl; then
       lt_cv_sys_max_cmd_len=`/sbin/sysctl -n kern.argmax`
@@ -1757,7 +1768,7 @@
   sysv5* | sco5v6* | sysv4.2uw2*)
     kargmax=`grep ARG_MAX /etc/conf/cf.d/stune 2>/dev/null`
     if test -n "$kargmax"; then
-      lt_cv_sys_max_cmd_len=`echo $kargmax | sed 's/.*[[	 ]]//'`
+      lt_cv_sys_max_cmd_len=`echo $kargmax | $SED 's/.*[[	 ]]//'`
     else
       lt_cv_sys_max_cmd_len=32768
     fi
@@ -2207,26 +2218,35 @@
 striplib=
 old_striplib=
 AC_MSG_CHECKING([whether stripping libraries is possible])
-if test -n "$STRIP" && $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
-  test -z "$old_striplib" && old_striplib="$STRIP --strip-debug"
-  test -z "$striplib" && striplib="$STRIP --strip-unneeded"
-  AC_MSG_RESULT([yes])
+if test -z "$STRIP"; then
+  AC_MSG_RESULT([no])
 else
-# FIXME - insert some real tests, host_os isn't really good enough
-  case $host_os in
-  darwin*)
-    if test -n "$STRIP"; then
+  if $STRIP -V 2>&1 | $GREP "GNU strip" >/dev/null; then
+    old_striplib="$STRIP --strip-debug"
+    striplib="$STRIP --strip-unneeded"
+    AC_MSG_RESULT([yes])
+  else
+    case $host_os in
+    darwin*)
+      # FIXME - insert some real tests, host_os isn't really good enough
       striplib="$STRIP -x"
       old_striplib="$STRIP -S"
       AC_MSG_RESULT([yes])
-    else
+      ;;
+    freebsd*)
+      if $STRIP -V 2>&1 | $GREP "elftoolchain" >/dev/null; then
+        old_striplib="$STRIP --strip-debug"
+        striplib="$STRIP --strip-unneeded"
+        AC_MSG_RESULT([yes])
+      else
+        AC_MSG_RESULT([no])
+      fi
+      ;;
+    *)
       AC_MSG_RESULT([no])
-    fi
-    ;;
-  *)
-    AC_MSG_RESULT([no])
-    ;;
-  esac
+      ;;
+    esac
+  fi
 fi
 _LT_DECL([], [old_striplib], [1], [Commands to strip libraries])
 _LT_DECL([], [striplib], [1])
@@ -2549,7 +2569,7 @@
     case $host_os in
     cygwin*)
       # Cygwin DLLs use 'cyg' prefix rather than 'lib'
-      soname_spec='`echo $libname | sed -e 's/^lib/cyg/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
+      soname_spec='`echo $libname | $SED -e 's/^lib/cyg/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
 m4_if([$1], [],[
       sys_lib_search_path_spec="$sys_lib_search_path_spec /usr/lib/w32api"])
       ;;
@@ -2559,14 +2579,14 @@
       ;;
     pw32*)
       # pw32 DLLs use 'pw' prefix rather than 'lib'
-      library_names_spec='`echo $libname | sed -e 's/^lib/pw/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
+      library_names_spec='`echo $libname | $SED -e 's/^lib/pw/'``echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
       ;;
     esac
     dynamic_linker='Win32 ld.exe'
     ;;
 
-  *,cl*)
-    # Native MSVC
+  *,cl* | *,icl*)
+    # Native MSVC or ICC
     libname_spec='$name'
     soname_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext'
     library_names_spec='$libname.dll.lib'
@@ -2585,7 +2605,7 @@
       done
       IFS=$lt_save_ifs
       # Convert to MSYS style.
-      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | sed -e 's|\\\\|/|g' -e 's| \\([[a-zA-Z]]\\):| /\\1|g' -e 's|^ ||'`
+      sys_lib_search_path_spec=`$ECHO "$sys_lib_search_path_spec" | $SED -e 's|\\\\|/|g' -e 's| \\([[a-zA-Z]]\\):| /\\1|g' -e 's|^ ||'`
       ;;
     cygwin*)
       # Convert to unix form, then to dos form, then back to unix form
@@ -2622,7 +2642,7 @@
     ;;
 
   *)
-    # Assume MSVC wrapper
+    # Assume MSVC and ICC wrapper
     library_names_spec='$libname`echo $release | $SED -e 's/[[.]]/-/g'`$versuffix$shared_ext $libname.lib'
     dynamic_linker='Win32 ld.exe'
     ;;
@@ -2655,7 +2675,7 @@
   shlibpath_var=LD_LIBRARY_PATH
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   # DragonFly does not have aout.  When/if they implement a new
   # versioning mechanism, adjust this.
   if test -x /usr/bin/objformat; then
@@ -3454,7 +3474,7 @@
 
 bsdi[[45]]*)
   lt_cv_deplibs_check_method='file_magic ELF [[0-9]][[0-9]]*-bit [[ML]]SB (shared object|dynamic lib)'
-  lt_cv_file_magic_cmd='/usr/bin/file -L'
+  lt_cv_file_magic_cmd='$FILECMD -L'
   lt_cv_file_magic_test_file=/shlib/libc.so
   ;;
 
@@ -3488,14 +3508,14 @@
   lt_cv_deplibs_check_method=pass_all
   ;;
 
-freebsd* | dragonfly*)
+freebsd* | dragonfly* | midnightbsd*)
   if echo __ELF__ | $CC -E - | $GREP __ELF__ > /dev/null; then
     case $host_cpu in
     i*86 )
       # Not sure whether the presence of OpenBSD here was a mistake.
       # Let's accept both of them until this is cleared up.
       lt_cv_deplibs_check_method='file_magic (FreeBSD|OpenBSD|DragonFly)/i[[3-9]]86 (compact )?demand paged shared library'
-      lt_cv_file_magic_cmd=/usr/bin/file
+      lt_cv_file_magic_cmd=$FILECMD
       lt_cv_file_magic_test_file=`echo /usr/lib/libc.so.*`
       ;;
     esac
@@ -3509,7 +3529,7 @@
   ;;
 
 hpux10.20* | hpux11*)
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   case $host_cpu in
   ia64*)
     lt_cv_deplibs_check_method='file_magic (s[[0-9]][[0-9]][[0-9]]|ELF-[[0-9]][[0-9]]) shared object file - IA64'
@@ -3556,7 +3576,7 @@
 
 newos6*)
   lt_cv_deplibs_check_method='file_magic ELF [[0-9]][[0-9]]*-bit [[ML]]SB (executable|dynamic lib)'
-  lt_cv_file_magic_cmd=/usr/bin/file
+  lt_cv_file_magic_cmd=$FILECMD
   lt_cv_file_magic_test_file=/usr/lib/libnls.so
   ;;
 
@@ -3683,13 +3703,13 @@
 	mingw*) lt_bad_file=conftest.nm/nofile ;;
 	*) lt_bad_file=/dev/null ;;
 	esac
-	case `"$tmp_nm" -B $lt_bad_file 2>&1 | sed '1q'` in
+	case `"$tmp_nm" -B $lt_bad_file 2>&1 | $SED '1q'` in
 	*$lt_bad_file* | *'Invalid file or object type'*)
 	  lt_cv_path_NM="$tmp_nm -B"
 	  break 2
 	  ;;
 	*)
-	  case `"$tmp_nm" -p /dev/null 2>&1 | sed '1q'` in
+	  case `"$tmp_nm" -p /dev/null 2>&1 | $SED '1q'` in
 	  */dev/null*)
 	    lt_cv_path_NM="$tmp_nm -p"
 	    break 2
@@ -3715,7 +3735,7 @@
     # Let the user override the test.
   else
     AC_CHECK_TOOLS(DUMPBIN, [dumpbin "link -dump"], :)
-    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | sed '1q'` in
+    case `$DUMPBIN -symbols -headers /dev/null 2>&1 | $SED '1q'` in
     *COFF*)
       DUMPBIN="$DUMPBIN -symbols -headers"
       ;;
@@ -3955,7 +3975,7 @@
 
 if test "$lt_cv_nm_interface" = "MS dumpbin"; then
   # Gets list of data symbols to import.
-  lt_cv_sys_global_symbol_to_import="sed -n -e 's/^I .* \(.*\)$/\1/p'"
+  lt_cv_sys_global_symbol_to_import="$SED -n -e 's/^I .* \(.*\)$/\1/p'"
   # Adjust the below global symbol transforms to fixup imported variables.
   lt_cdecl_hook=" -e 's/^I .* \(.*\)$/extern __declspec(dllimport) char \1;/p'"
   lt_c_name_hook=" -e 's/^I .* \(.*\)$/  {\"\1\", (void *) 0},/p'"
@@ -3973,20 +3993,20 @@
 # Transform an extracted symbol line into a proper C declaration.
 # Some systems (esp. on ia64) link data and code symbols differently,
 # so use this general approach.
-lt_cv_sys_global_symbol_to_cdecl="sed -n"\
+lt_cv_sys_global_symbol_to_cdecl="$SED -n"\
 $lt_cdecl_hook\
 " -e 's/^T .* \(.*\)$/extern int \1();/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/extern char \1;/p'"
 
 # Transform an extracted symbol line into symbol name and symbol address
-lt_cv_sys_global_symbol_to_c_name_address="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address="$SED -n"\
 $lt_c_name_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(.*\)$/  {\"\1\", (void *) \&\1},/p'"
 
 # Transform an extracted symbol line into symbol name with lib prefix and
 # symbol address.
-lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="sed -n"\
+lt_cv_sys_global_symbol_to_c_name_address_lib_prefix="$SED -n"\
 $lt_c_name_lib_hook\
 " -e 's/^: \(.*\) .*$/  {\"\1\", (void *) 0},/p'"\
 " -e 's/^$symcode$symcode* .* \(lib.*\)$/  {\"\1\", (void *) \&\1},/p'"\
@@ -4010,7 +4030,7 @@
   if test "$lt_cv_nm_interface" = "MS dumpbin"; then
     # Fake it for dumpbin and say T for any non-static function,
     # D for any global variable and I for any imported variable.
-    # Also find C++ and __fastcall symbols from MSVC++,
+    # Also find C++ and __fastcall symbols from MSVC++ or ICC,
     # which start with @ or ?.
     lt_cv_sys_global_symbol_pipe="$AWK ['"\
 "     {last_section=section; section=\$ 3};"\
@@ -4028,9 +4048,9 @@
 "     s[1]~prfx {split(s[1],t,\"@\"); print f,t[1],substr(t[1],length(prfx))}"\
 "     ' prfx=^$ac_symprfx]"
   else
-    lt_cv_sys_global_symbol_pipe="sed -n -e 's/^.*[[	 ]]\($symcode$symcode*\)[[	 ]][[	 ]]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
+    lt_cv_sys_global_symbol_pipe="$SED -n -e 's/^.*[[	 ]]\($symcode$symcode*\)[[	 ]][[	 ]]*$ac_symprfx$sympat$opt_cr$/$symxfrm/p'"
   fi
-  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | sed '/ __gnu_lto/d'"
+  lt_cv_sys_global_symbol_pipe="$lt_cv_sys_global_symbol_pipe | $SED '/ __gnu_lto/d'"
 
   # Check to see that the pipe works correctly.
   pipe_works=no
@@ -4317,7 +4337,7 @@
 	    ;;
 	esac
 	;;
-      freebsd* | dragonfly*)
+      freebsd* | dragonfly* | midnightbsd*)
 	# FreeBSD uses GNU C++
 	;;
       hpux9* | hpux10* | hpux11*)
@@ -4400,7 +4420,7 @@
 	    _LT_TAGVAR(lt_prog_compiler_static, $1)='-qstaticlink'
 	    ;;
 	  *)
-	    case `$CC -V 2>&1 | sed 5q` in
+	    case `$CC -V 2>&1 | $SED 5q` in
 	    *Sun\ C*)
 	      # Sun C++ 5.9
 	      _LT_TAGVAR(lt_prog_compiler_pic, $1)='-KPIC'
@@ -4736,7 +4756,7 @@
 	_LT_TAGVAR(lt_prog_compiler_static, $1)='-qstaticlink'
 	;;
       *)
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ Ceres\ Fortran* | *Sun*Fortran*\ [[1-7]].* | *Sun*Fortran*\ 8.[[0-3]]*)
 	  # Sun Fortran 8.3 passes all unrecognized flags to the linker
 	  _LT_TAGVAR(lt_prog_compiler_pic, $1)='-KPIC'
@@ -4919,7 +4939,7 @@
     if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
       _LT_TAGVAR(export_symbols_cmds, $1)='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && ([substr](\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
     else
-      _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+      _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
     fi
     ;;
   pw32*)
@@ -4927,7 +4947,7 @@
     ;;
   cygwin* | mingw* | cegcc*)
     case $cc_basename in
-    cl*)
+    cl* | icl*)
       _LT_TAGVAR(exclude_expsyms, $1)='_NULL_IMPORT_DESCRIPTOR|_IMPORT_DESCRIPTOR_.*'
       ;;
     *)
@@ -4984,15 +5004,15 @@
 
   case $host_os in
   cygwin* | mingw* | pw32* | cegcc*)
-    # FIXME: the MSVC++ port hasn't been tested in a loooong time
+    # FIXME: the MSVC++ and ICC port hasn't been tested in a loooong time
     # When not using gcc, we currently assume that we are using
-    # Microsoft Visual C++.
+    # Microsoft Visual C++ or Intel C++ Compiler.
     if test yes != "$GCC"; then
       with_gnu_ld=no
     fi
     ;;
   interix*)
-    # we just hope/assume this is gcc and not c89 (= MSVC++)
+    # we just hope/assume this is gcc and not c89 (= MSVC++ or ICC)
     with_gnu_ld=yes
     ;;
   openbsd* | bitrig*)
@@ -5044,7 +5064,7 @@
       _LT_TAGVAR(whole_archive_flag_spec, $1)=
     fi
     supports_anon_versioning=no
-    case `$LD -v | $SED -e 's/([^)]\+)\s\+//' 2>&1` in
+    case `$LD -v | $SED -e 's/([[^)]]\+)\s\+//' 2>&1` in
       *GNU\ gold*) supports_anon_versioning=yes ;;
       *\ [[01]].* | *\ 2.[[0-9]].* | *\ 2.10.*) ;; # catch versions < 2.11
       *\ 2.11.93.0.2\ *) supports_anon_versioning=yes ;; # RH7.3 ...
@@ -5156,6 +5176,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       _LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       _LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+      _LT_TAGVAR(file_list_spec, $1)='@'
       ;;
 
     interix[[3-9]]*)
@@ -5170,7 +5191,7 @@
       # 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
       # time.  Moving up from 0x10000000 also allows more sbrk(2) space.
       _LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-      _LT_TAGVAR(archive_expsym_cmds, $1)='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+      _LT_TAGVAR(archive_expsym_cmds, $1)='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
       ;;
 
     gnu* | linux* | tpf* | k*bsd*-gnu | kopensolaris*-gnu)
@@ -5213,7 +5234,7 @@
 	  _LT_TAGVAR(compiler_needs_object, $1)=yes
 	  ;;
 	esac
-	case `$CC -V 2>&1 | sed 5q` in
+	case `$CC -V 2>&1 | $SED 5q` in
 	*Sun\ C*)			# Sun C 5.9
 	  _LT_TAGVAR(whole_archive_flag_spec, $1)='$wl--whole-archive`new_convenience=; for conv in $convenience\"\"; do test -z \"$conv\" || new_convenience=\"$new_convenience,$conv\"; done; func_echo_all \"$new_convenience\"` $wl--no-whole-archive'
 	  _LT_TAGVAR(compiler_needs_object, $1)=yes
@@ -5225,7 +5246,7 @@
 
         if test yes = "$supports_anon_versioning"; then
           _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-            cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+            cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
             echo "local: *; };" >> $output_objdir/$libname.ver~
             $CC '"$tmp_sharedflag""$tmp_addflag"' $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
         fi
@@ -5241,7 +5262,7 @@
 	  _LT_TAGVAR(archive_cmds, $1)='$LD -shared $libobjs $deplibs $linker_flags -soname $soname -o $lib'
 	  if test yes = "$supports_anon_versioning"; then
 	    _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-              cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+              cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
               echo "local: *; };" >> $output_objdir/$libname.ver~
               $LD -shared $libobjs $deplibs $linker_flags -soname $soname -version-script $output_objdir/$libname.ver -o $lib'
 	  fi
@@ -5373,7 +5394,7 @@
 	if $NM -V 2>&1 | $GREP 'GNU' > /dev/null; then
 	  _LT_TAGVAR(export_symbols_cmds, $1)='$NM -Bpg $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W")) && ([substr](\$ 3,1,1) != ".")) { if (\$ 2 == "W") { print \$ 3 " weak" } else { print \$ 3 } } }'\'' | sort -u > $export_symbols'
 	else
-	  _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
+	  _LT_TAGVAR(export_symbols_cmds, $1)='`func_echo_all $NM | $SED -e '\''s/B\([[^B]]*\)$/P\1/'\''` -PCpgl $libobjs $convenience | awk '\''{ if (((\$ 2 == "T") || (\$ 2 == "D") || (\$ 2 == "B") || (\$ 2 == "L") || (\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) && ([substr](\$ 1,1,1) != ".")) { if ((\$ 2 == "W") || (\$ 2 == "V") || (\$ 2 == "Z")) { print \$ 1 " weak" } else { print \$ 1 } } }'\'' | sort -u > $export_symbols'
 	fi
 	aix_use_runtimelinking=no
 
@@ -5556,12 +5577,12 @@
 
     cygwin* | mingw* | pw32* | cegcc*)
       # When not using gcc, we currently assume that we are using
-      # Microsoft Visual C++.
+      # Microsoft Visual C++ or Intel C++ Compiler.
       # hardcode_libdir_flag_spec is actually meaningless, as there is
       # no search path for DLLs.
       case $cc_basename in
-      cl*)
-	# Native MSVC
+      cl* | icl*)
+	# Native MSVC or ICC
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	_LT_TAGVAR(always_export_symbols, $1)=yes
@@ -5602,7 +5623,7 @@
           fi'
 	;;
       *)
-	# Assume MSVC wrapper
+	# Assume MSVC and ICC wrapper
 	_LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
 	_LT_TAGVAR(allow_undefined_flag, $1)=unsupported
 	# Tell ltmain to make .lib files, not .a files.
@@ -5650,7 +5671,7 @@
       ;;
 
     # FreeBSD 3 and greater uses gcc -shared to do shared libraries.
-    freebsd* | dragonfly*)
+    freebsd* | dragonfly* | midnightbsd*)
       _LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag -o $lib $libobjs $deplibs $compiler_flags'
       _LT_TAGVAR(hardcode_libdir_flag_spec, $1)='-R$libdir'
       _LT_TAGVAR(hardcode_direct, $1)=yes
@@ -5861,6 +5882,7 @@
 	emximp -o $lib $output_objdir/$libname.def'
       _LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
       _LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+      _LT_TAGVAR(file_list_spec, $1)='@'
       ;;
 
     osf3*)
@@ -6631,8 +6653,8 @@
 
       cygwin* | mingw* | pw32* | cegcc*)
 	case $GXX,$cc_basename in
-	,cl* | no,cl*)
-	  # Native MSVC
+	,cl* | no,cl* | ,icl* | no,icl*)
+	  # Native MSVC or ICC
 	  # hardcode_libdir_flag_spec is actually meaningless, as there is
 	  # no search path for DLLs.
 	  _LT_TAGVAR(hardcode_libdir_flag_spec, $1)=' '
@@ -6730,6 +6752,7 @@
 	  emximp -o $lib $output_objdir/$libname.def'
 	_LT_TAGVAR(old_archive_From_new_cmds, $1)='emximp -o $output_objdir/${libname}_dll.a $output_objdir/$libname.def'
 	_LT_TAGVAR(enable_shared_with_static_runtimes, $1)=yes
+	_LT_TAGVAR(file_list_spec, $1)='@'
 	;;
 
       dgux*)
@@ -6760,7 +6783,7 @@
         _LT_TAGVAR(archive_cmds_need_lc, $1)=no
         ;;
 
-      freebsd* | dragonfly*)
+      freebsd* | dragonfly* | midnightbsd*)
         # FreeBSD 3 and later use GNU C++ and GNU ld with standard ELF
         # conventions
         _LT_TAGVAR(ld_shlibs, $1)=yes
@@ -6897,7 +6920,7 @@
 	# 256 KiB-aligned image base between 0x50000000 and 0x6FFC0000 at link
 	# time.  Moving up from 0x10000000 also allows more sbrk(2) space.
 	_LT_TAGVAR(archive_cmds, $1)='$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
-	_LT_TAGVAR(archive_expsym_cmds, $1)='sed "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
+	_LT_TAGVAR(archive_expsym_cmds, $1)='$SED "s|^|_|" $export_symbols >$output_objdir/$soname.expsym~$CC -shared $pic_flag $libobjs $deplibs $compiler_flags $wl-h,$soname $wl--retain-symbols-file,$output_objdir/$soname.expsym $wl--image-base,`expr ${RANDOM-$$} % 4096 / 2 \* 262144 + 1342177280` -o $lib'
 	;;
       irix5* | irix6*)
         case $cc_basename in
@@ -7037,13 +7060,13 @@
 	    _LT_TAGVAR(archive_cmds, $1)='$CC -qmkshrobj $libobjs $deplibs $compiler_flags $wl-soname $wl$soname -o $lib'
 	    if test yes = "$supports_anon_versioning"; then
 	      _LT_TAGVAR(archive_expsym_cmds, $1)='echo "{ global:" > $output_objdir/$libname.ver~
-                cat $export_symbols | sed -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
+                cat $export_symbols | $SED -e "s/\(.*\)/\1;/" >> $output_objdir/$libname.ver~
                 echo "local: *; };" >> $output_objdir/$libname.ver~
                 $CC -qmkshrobj $libobjs $deplibs $compiler_flags $wl-soname $wl$soname $wl-version-script $wl$output_objdir/$libname.ver -o $lib'
 	    fi
 	    ;;
 	  *)
-	    case `$CC -V 2>&1 | sed 5q` in
+	    case `$CC -V 2>&1 | $SED 5q` in
 	    *Sun\ C*)
 	      # Sun C++ 5.9
 	      _LT_TAGVAR(no_undefined_flag, $1)=' -zdefs'
@@ -8189,6 +8212,14 @@
 AC_SUBST([DLLTOOL])
 ])
 
+# _LT_DECL_FILECMD
+# ----------------
+# Check for a file(cmd) program that can be used to detect file type and magic
+m4_defun([_LT_DECL_FILECMD],
+[AC_CHECK_TOOL([FILECMD], [file], [:])
+_LT_DECL([], [FILECMD], [1], [A file(cmd) program that detects file types])
+])# _LD_DECL_FILECMD
+
 # _LT_DECL_SED
 # ------------
 # Check for a fully-functional sed program, that truncates
diff --git a/scripts/ltoptions.m4 b/scripts/autoconf/ltoptions.m4
similarity index 98%
rename from scripts/ltoptions.m4
rename to scripts/autoconf/ltoptions.m4
index 94b0829..b0b5e9c 100644
--- a/scripts/ltoptions.m4
+++ b/scripts/autoconf/ltoptions.m4
@@ -1,7 +1,7 @@
 # Helper functions for option handling.                    -*- Autoconf -*-
 #
-#   Copyright (C) 2004-2005, 2007-2009, 2011-2015 Free Software
-#   Foundation, Inc.
+#   Copyright (C) 2004-2005, 2007-2009, 2011-2019, 2021-2022 Free
+#   Software Foundation, Inc.
 #   Written by Gary V. Vaughan, 2004
 #
 # This file is free software; the Free Software Foundation gives
diff --git a/scripts/ltsugar.m4 b/scripts/autoconf/ltsugar.m4
similarity index 97%
rename from scripts/ltsugar.m4
rename to scripts/autoconf/ltsugar.m4
index 48bc934..902508b 100644
--- a/scripts/ltsugar.m4
+++ b/scripts/autoconf/ltsugar.m4
@@ -1,6 +1,6 @@
 # ltsugar.m4 -- libtool m4 base layer.                         -*-Autoconf-*-
 #
-# Copyright (C) 2004-2005, 2007-2008, 2011-2015 Free Software
+# Copyright (C) 2004-2005, 2007-2008, 2011-2019, 2021-2022 Free Software
 # Foundation, Inc.
 # Written by Gary V. Vaughan, 2004
 #
diff --git a/scripts/ltversion.m4 b/scripts/autoconf/ltversion.m4
similarity index 66%
rename from scripts/ltversion.m4
rename to scripts/autoconf/ltversion.m4
index fa04b52..b155d0a 100644
--- a/scripts/ltversion.m4
+++ b/scripts/autoconf/ltversion.m4
@@ -1,6 +1,7 @@
 # ltversion.m4 -- version numbers			-*- Autoconf -*-
 #
-#   Copyright (C) 2004, 2011-2015 Free Software Foundation, Inc.
+#   Copyright (C) 2004, 2011-2019, 2021-2022 Free Software Foundation,
+#   Inc.
 #   Written by Scott James Remnant, 2004
 #
 # This file is free software; the Free Software Foundation gives
@@ -9,15 +10,15 @@
 
 # @configure_input@
 
-# serial 4179 ltversion.m4
+# serial 4245 ltversion.m4
 # This file is part of GNU Libtool
 
-m4_define([LT_PACKAGE_VERSION], [2.4.6])
-m4_define([LT_PACKAGE_REVISION], [2.4.6])
+m4_define([LT_PACKAGE_VERSION], [2.4.7])
+m4_define([LT_PACKAGE_REVISION], [2.4.7])
 
 AC_DEFUN([LTVERSION_VERSION],
-[macro_version='2.4.6'
-macro_revision='2.4.6'
+[macro_version='2.4.7'
+macro_revision='2.4.7'
 _LT_DECL(, macro_version, 0, [Which release of libtool.m4 was used?])
 _LT_DECL(, macro_revision, 0)
 ])
diff --git a/scripts/lt~obsolete.m4 b/scripts/autoconf/lt~obsolete.m4
similarity index 98%
rename from scripts/lt~obsolete.m4
rename to scripts/autoconf/lt~obsolete.m4
index c6b26f8..0f7a875 100644
--- a/scripts/lt~obsolete.m4
+++ b/scripts/autoconf/lt~obsolete.m4
@@ -1,7 +1,7 @@
 # lt~obsolete.m4 -- aclocal satisfying obsolete definitions.    -*-Autoconf-*-
 #
-#   Copyright (C) 2004-2005, 2007, 2009, 2011-2015 Free Software
-#   Foundation, Inc.
+#   Copyright (C) 2004-2005, 2007, 2009, 2011-2019, 2021-2022 Free
+#   Software Foundation, Inc.
 #   Written by Scott James Remnant, 2004.
 #
 # This file is free software; the Free Software Foundation gives
diff --git a/scripts/checksym.awk b/scripts/checksym.awk
index fe3af55..2ab52ec 100755
--- a/scripts/checksym.awk
+++ b/scripts/checksym.awk
@@ -1,4 +1,5 @@
 #!/bin/awk -f
+
 # Check a list of symbols against the master definition
 # (official) list.  Arguments:
 #
@@ -105,11 +106,13 @@
 # At the end check for symbols marked as both duplicated and removed
 END{
    if (symbolo > lasto) {
-      print "highest symbol ordinal in png.h,", symbolo ", exceeds last ordinal from png.h", lasto
+      print "highest symbol ordinal in png.h,",
+            symbolo ", exceeds last ordinal from png.h", lasto
       err = 1
    }
    if (mastero > lasto) {
-      print "highest symbol ordinal in", master ",", mastero ", exceeds last ordinal from png.h", lasto
+      print "highest symbol ordinal in", master ",",
+            mastero ", exceeds last ordinal from png.h", lasto
       err = 1
    }
    unexported=0
@@ -148,17 +151,21 @@
          unexported = 0
       }
       if (symbol[o] != "" && removed[o] != "") {
-         print "png.h: symbol", o, "both exported as '" symbol[o] "' and removed as '" removed[o] "'"
+         print "png.h: symbol", o,
+               "both exported as '" symbol[o] "' and removed as '" removed[o] "'"
          err = 1
       } else if (symbol[o] != official[o]) {
          # either the symbol is missing somewhere or it changed
          err = 1
          if (symbol[o] == "")
-            print "png.h: symbol", o, "is exported as '" official[o] "' in", master
+            print "png.h: symbol", o,
+                  "is exported as '" official[o] "' in", master
          else if (official[o] == "")
-            print "png.h: exported symbol", o, "'" symbol[o] "' not present in", master
+            print "png.h: exported symbol", o,
+                  "'" symbol[o] "' not present in", master
          else
-            print "png.h: exported symbol", o, "'" symbol[o] "' exists as '" official[o] "' in", master
+            print "png.h: exported symbol", o,
+                  "'" symbol[o] "' exists as '" official[o] "' in", master
       }
 
       # Finally generate symbols.new
diff --git a/scripts/cmake/AUTHORS.md b/scripts/cmake/AUTHORS.md
new file mode 100644
index 0000000..1c1173a
--- /dev/null
+++ b/scripts/cmake/AUTHORS.md
@@ -0,0 +1,35 @@
+CMake Files, Lists and Scripts for the PNG Reference Library
+============================================================
+
+Author List
+-----------
+
+ * Alex Gaynor
+ * Andreas Franek
+ * B. Scott Michel
+ * Cameron Cawley
+ * Christian Ehrlicher
+ * Christopher Sean Morrison
+ * Claudio Bley
+ * Clifford Yapp
+ * Clinton Ingram
+ * Cosmin Truta
+ * David Callu
+ * Gleb Mazovetskiy
+ * Glenn Randers-Pehrson
+ * Gunther Nikl
+ * Jeremy Maitin-Shepard
+ * John Bowler
+ * Jon Creighton
+ * Kyle Bentley
+ * Martin Storsjö
+ * Owen Rudge
+ * Roger Leigh
+ * Roger Lowman
+ * Sam Serrels
+ * Simon Hausmann
+ * Steve Robinson
+ * Timothy Lyanguzov
+ * Tyler Kropp
+ * Vadim Barkov
+ * Vicky Pfau
diff --git a/scripts/cmake/README.md b/scripts/cmake/README.md
new file mode 100644
index 0000000..ca41889
--- /dev/null
+++ b/scripts/cmake/README.md
@@ -0,0 +1,35 @@
+CMake Files, Lists and Scripts for the PNG Reference Library
+============================================================
+
+Copyright Notice
+----------------
+
+ * Copyright (c) 2018-2024 Cosmin Truta.
+ * Copyright (c) 2007-2018 Glenn Randers-Pehrson.
+ * Originally written by Christian Ehrlicher, 2007.
+
+Use, modification and distribution of the CMake
+files in the libpng distribution are subject to
+the same licensing terms and conditions as libpng.
+Please see the copyright notice in `png.h` or visit
+http://libpng.org/pub/png/src/libpng-LICENSE.txt
+
+File List
+---------
+
+    CMakeLists.txt                 ==>  The main CMake lists file
+    scripts/cmake/AUTHORS.md       ==>  The Authors file
+    scripts/cmake/README.md        ==>  This file
+    scripts/cmake/genchk.cmake.in  ==>  Template for genchk.cmake
+    scripts/cmake/genout.cmake.in  ==>  Template for genout.cmake
+    scripts/cmake/gensrc.cmake.in  ==>  Template for gensrc.cmake
+    scripts/cmake/test.cmake.in    ==>  Template for test.cmake
+
+Acknowledgements
+----------------
+
+See the accompanying file `scripts/cmake/AUTHORS.md`
+for the list of Contributing Authors.
+
+If you are a Contributing Author, please make sure
+that you are being acknowledged.
diff --git a/scripts/genchk.cmake.in b/scripts/cmake/genchk.cmake.in
similarity index 69%
rename from scripts/genchk.cmake.in
rename to scripts/cmake/genchk.cmake.in
index ab3b9d7..5ea92dd 100644
--- a/scripts/genchk.cmake.in
+++ b/scripts/cmake/genchk.cmake.in
@@ -1,15 +1,20 @@
 # genchk.cmake.in
 # Generate .chk from .out with awk (generic), based upon the automake logic.
 
-# Copyright (C) 2016 Glenn Randers-Pehrson
+# Copyright (c) 2022-2024 Cosmin Truta
+# Copyright (c) 2016 Glenn Randers-Pehrson
 # Written by Roger Leigh, 2016
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
+#
+# Use, modification and distribution are subject to
+# the same licensing terms and conditions as libpng.
+# Please see the copyright notice in png.h or visit
+# http://libpng.org/pub/png/src/libpng-LICENSE.txt
+#
+# SPDX-License-Identifier: libpng-2.0
 
 # Variables substituted from CMakeLists.txt
 set(SRCDIR "@CMAKE_CURRENT_SOURCE_DIR@")
+set(BINDIR "@CMAKE_CURRENT_BINARY_DIR@")
 
 set(AWK "@AWK@")
 
@@ -20,10 +25,10 @@
 get_filename_component(INPUTDIR "${INPUT}" PATH)
 get_filename_component(OUTPUTDIR "${OUTPUT}" PATH)
 
-if("${INPUTEXT}" STREQUAL ".out" AND "${OUTPUTEXT}" STREQUAL ".chk")
+if(INPUTEXT STREQUAL ".out" AND OUTPUTEXT STREQUAL ".chk")
   # Generate .chk from .out with awk (generic)
   file(REMOVE "${OUTPUT}" "${OUTPUTDIR}/${OUTPUTBASE}.new")
-  execute_process(COMMAND "${AWK}" -f "${SRCDIR}/scripts/checksym.awk"
+  execute_process(COMMAND "${AWK}" -f "${BINDIR}/scripts/checksym.awk"
                           "${SRCDIR}/scripts/${INPUTBASE}.def"
                           "of=${OUTPUTDIR}/${OUTPUTBASE}.new"
                           "${INPUT}"
diff --git a/scripts/genout.cmake.in b/scripts/cmake/genout.cmake.in
similarity index 81%
rename from scripts/genout.cmake.in
rename to scripts/cmake/genout.cmake.in
index 01f12de..ab82859 100644
--- a/scripts/genout.cmake.in
+++ b/scripts/cmake/genout.cmake.in
@@ -1,12 +1,16 @@
 # genout.cmake.in
 # Generate .out from .c with awk (generic), based upon the automake logic.
 
-# Copyright (C) 2016 Glenn Randers-Pehrson
+# Copyright (c) 2022-2024 Cosmin Truta
+# Copyright (c) 2016 Glenn Randers-Pehrson
 # Written by Roger Leigh, 2016
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
+#
+# Use, modification and distribution are subject to
+# the same licensing terms and conditions as libpng.
+# Please see the copyright notice in png.h or visit
+# http://libpng.org/pub/png/src/libpng-LICENSE.txt
+#
+# SPDX-License-Identifier: libpng-2.0
 
 # Variables substituted from CMakeLists.txt
 set(SRCDIR "@CMAKE_CURRENT_SOURCE_DIR@")
@@ -20,14 +24,14 @@
 set(PNGLIB_MAJOR "@PNGLIB_MAJOR@")
 set(PNGLIB_MINOR "@PNGLIB_MINOR@")
 set(PNGLIB_VERSION "@PNGLIB_VERSION@")
-set(ZLIBINCDIR "@ZLIB_INCLUDE_DIR@")
+set(ZLIBINCDIR "@ZLIB_INCLUDE_DIRS@")
 
 set(PLATFORM_C_FLAGS)
 if(APPLE)
-  set(CMAKE_OSX_ARCHITECTURES "@CMAKE_OSX_ARCHITECTURES@")
+  set(CMAKE_OSX_INTERNAL_ARCHITECTURES "@CMAKE_OSX_INTERNAL_ARCHITECTURES@")
   set(CMAKE_OSX_SYSROOT "@CMAKE_OSX_SYSROOT@")
-  if(CMAKE_OSX_ARCHITECTURES)
-    set(PLATFORM_C_FLAGS ${PLATFORM_C_FLAGS} -arch ${CMAKE_OSX_ARCHITECTURES})
+  if(CMAKE_OSX_INTERNAL_ARCHITECTURES)
+    set(PLATFORM_C_FLAGS ${PLATFORM_C_FLAGS} -arch ${CMAKE_OSX_INTERNAL_ARCHITECTURES})
   endif()
   if(CMAKE_OSX_SYSROOT)
     set(PLATFORM_C_FLAGS ${PLATFORM_C_FLAGS} -isysroot ${CMAKE_OSX_SYSROOT})
@@ -41,7 +45,7 @@
 get_filename_component(INPUTDIR "${INPUT}" PATH)
 get_filename_component(OUTPUTDIR "${OUTPUT}" PATH)
 
-if ("${INPUTEXT}" STREQUAL ".c" AND "${OUTPUTEXT}" STREQUAL ".out")
+if(INPUTEXT STREQUAL ".c" AND OUTPUTEXT STREQUAL ".out")
   get_filename_component(GENDIR "${OUTPUT}" PATH)
   file(MAKE_DIRECTORY "${GENDIR}")
 
diff --git a/scripts/gensrc.cmake.in b/scripts/cmake/gensrc.cmake.in
similarity index 87%
rename from scripts/gensrc.cmake.in
rename to scripts/cmake/gensrc.cmake.in
index f28a622..52dab8d 100644
--- a/scripts/gensrc.cmake.in
+++ b/scripts/cmake/gensrc.cmake.in
@@ -1,12 +1,16 @@
 # gensrc.cmake.in
 # Generate source files with awk, based upon the automake logic.
 
-# Copyright (C) 2016 Glenn Randers-Pehrson
+# Copyright (c) 2022-2024 Cosmin Truta
+# Copyright (c) 2016 Glenn Randers-Pehrson
 # Written by Roger Leigh, 2016
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
+#
+# Use, modification and distribution are subject to
+# the same licensing terms and conditions as libpng.
+# Please see the copyright notice in png.h or visit
+# http://libpng.org/pub/png/src/libpng-LICENSE.txt
+#
+# SPDX-License-Identifier: libpng-2.0
 
 # Variables substituted from CMakeLists.txt
 set(SRCDIR "@CMAKE_CURRENT_SOURCE_DIR@")
@@ -17,7 +21,7 @@
 set(PNG_PREFIX "@PNG_PREFIX@")
 set(PNGLIB_VERSION "@PNGLIB_VERSION@")
 
-if("${OUTPUT}" STREQUAL "scripts/pnglibconf.c")
+if(OUTPUT STREQUAL "scripts/pnglibconf.c")
   # Generate scripts/pnglibconf.c
 
   file(REMOVE "${BINDIR}/pnglibconf.tf6" "${BINDIR}/pnglibconf.tf7")
@@ -45,7 +49,7 @@
   file(MAKE_DIRECTORY "${BINDIR}/scripts")
   file(RENAME "pnglibconf.tf7" "${BINDIR}/scripts/pnglibconf.c")
 
-elseif ("${OUTPUT}" STREQUAL "pnglibconf.c")
+elseif(OUTPUT STREQUAL "pnglibconf.c")
   # Generate pnglibconf.c
 
   file(REMOVE "${BINDIR}/pnglibconf.tf4" "${BINDIR}/pnglibconf.tf5")
@@ -72,7 +76,7 @@
   file(MAKE_DIRECTORY "${BINDIR}/scripts")
   file(RENAME "pnglibconf.tf5" "${BINDIR}/pnglibconf.c")
 
-elseif ("${OUTPUT}" STREQUAL "pnglibconf.h")
+elseif(OUTPUT STREQUAL "pnglibconf.h")
   # Generate pnglibconf.h
 
   file(REMOVE "${BINDIR}/${OUTPUT}")
@@ -101,7 +105,7 @@
     endif()
   endif()
 
-elseif ("${OUTPUT}" STREQUAL "pngprefix.h")
+elseif(OUTPUT STREQUAL "pngprefix.h")
   # Generate pngprefix.h
 
   file(REMOVE "${BINDIR}/${OUTPUT}")
@@ -123,16 +127,18 @@
     file(WRITE "${BINDIR}/${OUTPUT}" "/* No libpng symbol prefix configured. */")
   endif()
 
-elseif("${OUTPUT}" STREQUAL "scripts/pnglibconf.h.prebuilt")
+elseif(OUTPUT STREQUAL "scripts/pnglibconf.h.prebuilt")
   # Generate scripts/pnglibconf.h.prebuilt (fails build)
 
   message(STATUS "Attempting to build scripts/pnglibconf.h.prebuilt")
   message(STATUS "This is a machine generated file, but if you want to make")
-  message(STATUS "a new one simply build the 'genfiles' target, and copy")
+  message(STATUS "a new one simply build the 'png_genfiles' target, and copy")
   message(STATUS "scripts/pnglibconf.out to scripts/pnglibconf.h.prebuilt")
   message(STATUS "AND set PNG_ZLIB_VERNUM to 0 (you MUST do this)")
   message(FATAL_ERROR "Stopping build")
 
 else()
+
   message(FATAL_ERROR "Unsupported output: ${OUTPUT}")
+
 endif()
diff --git a/scripts/test.cmake.in b/scripts/cmake/test.cmake.in
similarity index 63%
rename from scripts/test.cmake.in
rename to scripts/cmake/test.cmake.in
index fa6a889..a1cd30f 100644
--- a/scripts/test.cmake.in
+++ b/scripts/cmake/test.cmake.in
@@ -1,11 +1,15 @@
 # test.cmake.in
 
-# Copyright (C) 2016 Glenn Randers-Pehrson
+# Copyright (c) 2024 Cosmin Truta
+# Copyright (c) 2016 Glenn Randers-Pehrson
 # Written by Roger Leigh, 2016
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
+#
+# Use, modification and distribution are subject to
+# the same licensing terms and conditions as libpng.
+# Please see the copyright notice in png.h or visit
+# http://libpng.org/pub/png/src/libpng-LICENSE.txt
+#
+# SPDX-License-Identifier: libpng-2.0
 
 set(TEST_OPTIONS "@TEST_OPTIONS@")
 set(TEST_FILES "@TEST_FILES@")
@@ -22,8 +26,7 @@
   set(ENV{PATH} "${LIBPNG_DIR};$ENV{PATH}")
 endif()
 
-execute_process(COMMAND "${CMAKE_COMMAND}" -E echo "Running ${TEST_COMMAND}" ${TEST_OPTIONS} ${NATIVE_TEST_FILES})
-
+message("Running ${TEST_COMMAND}" ${TEST_OPTIONS} ${NATIVE_TEST_FILES})
 execute_process(COMMAND "${TEST_COMMAND}" ${TEST_OPTIONS} ${NATIVE_TEST_FILES}
                 RESULT_VARIABLE TEST_STATUS)
 if(TEST_STATUS)
diff --git a/scripts/descrip.mms b/scripts/descrip.mms
index a3aefbf..c440fc3 100644
--- a/scripts/descrip.mms
+++ b/scripts/descrip.mms
@@ -6,14 +6,11 @@
 pref = /prefix=all
 .endif
 
+OBJS = png.obj, pngerror.obj, pngget.obj, pngmem.obj, pngpread.obj,\
+       pngread.obj, pngrio.obj, pngrtran.obj, pngrutil.obj, pngset.obj,\
+       pngtrans.obj, pngwio.obj, pngwrite.obj, pngwtran.obj, pngwutil.obj
 
-
-OBJS = png.obj, pngset.obj, pngget.obj, pngrutil.obj, pngtrans.obj,\
-	pngwutil.obj, pngread.obj, pngmem.obj, pngwrite.obj, pngrtran.obj,\
-	pngwtran.obj, pngrio.obj, pngwio.obj, pngerror.obj, pngpread.obj
-
-
-CFLAGS= $(C_DEB) $(CC_DEFS) $(PREF)
+CFLAGS = $(C_DEB) $(CC_DEFS) $(PREF)
 
 all : pngtest.exe libpng.olb
 	@ write sys$output " pngtest available"
@@ -21,32 +18,30 @@
 libpng.olb : libpng.olb($(OBJS))
 	@ write sys$output " libpng available"
 
-
 pngtest.exe : pngtest.obj libpng.olb
-              link pngtest,libpng.olb/lib,$(ZLIBSRC)libz.olb/lib
+	link pngtest,libpng.olb/lib,$(ZLIBSRC)libz.olb/lib
 
 test : pngtest.exe
-   run pngtest
+	run pngtest
 
 clean :
 	delete *.obj;*,*.exe;
 
-
 # Other dependencies.
-png.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+png.obj :      png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngget.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngmem.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngpread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngset.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngget.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngread.obj :  png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngrio.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngrtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngrutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngmem.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngrio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
-pngwio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngset.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngtrans.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
+pngwio.obj :   png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwrite.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 pngwutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,pnginfo.h, pngdebug.h
 
-pngtest.obj : png.h, pngconf.h, pnglibconf.h
+pngtest.obj :  png.h, pngconf.h, pnglibconf.h
diff --git a/scripts/dfn.awk b/scripts/dfn.awk
index 346b9db..0b25c8a 100755
--- a/scripts/dfn.awk
+++ b/scripts/dfn.awk
Binary files differ
diff --git a/scripts/intprefix.c b/scripts/intprefix.c
index 254f8e9..4085e54 100644
--- a/scripts/intprefix.c
+++ b/scripts/intprefix.c
@@ -1,7 +1,6 @@
 
 /* intprefix.c - generate an unprefixed internal symbol list
  *
- * Last changed in libpng version 1.6.16 [December 22, 2014]
  * Copyright (c) 2013-2014 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
diff --git a/scripts/libpng-config-head.in b/scripts/libpng-config-head.in
index c1da02c..df8d662 100644
--- a/scripts/libpng-config-head.in
+++ b/scripts/libpng-config-head.in
@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.6.38.git
+version=1.6.43.git
 prefix=""
 libdir=""
 libs=""
diff --git a/scripts/libpng.pc.in b/scripts/libpng.pc.in
index 19afcc3..0fc82fa 100644
--- a/scripts/libpng.pc.in
+++ b/scripts/libpng.pc.in
@@ -5,6 +5,6 @@
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.6.38.git
+Version: 1.6.43.git
 Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}
diff --git a/scripts/makefile.32sunu b/scripts/makefile.32sunu
index c849ecd..822e8a9 100644
--- a/scripts/makefile.32sunu
+++ b/scripts/makefile.32sunu
@@ -1,38 +1,32 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
-
+#
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
 # Library name:
 LIBNAME=libpng16
-PNGMAJ = 16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
 CC=cc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -f -s
+AR=ar
 RANLIB=echo
+LN_SF=ln -f -s
 RM_F=/bin/rm -f
 
 SUN_CC_FLAGS=-fast -xtarget=ultra
 SUN_LD_FLAGS=-fast -xtarget=ultra
 
-# where make install puts libpng.a, libpng16.so and libpng16/png.h
-prefix=/a
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 # Changing these to ../zlib poses a security risk.  If you want
 # to have zlib in an adjacent directory, specify the full path instead of "..".
@@ -44,34 +38,15 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS=$(SUN_CC_FLAGS) # $(WARNMORE) -g
+ARFLAGS=rc
 LDFLAGS=$(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) libpng.a -lz -lm
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -83,36 +58,16 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -KPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 include scripts/pnglibconf.mak
 DELETE = $(RM_F)
 DFNFLAGS = $(DEFS) $(CPPFLAGS)
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo libdir=\"$(LIBPATH)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-R$(LIBPATH)\"; \
-	echo ccopts=\"-fast -xtarget=ultra\"; \
-	echo ldopts=\"-fast -xtarget=ultra\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -138,107 +93,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) $(SUN_CC_FLAGS) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtestd -L$(DL) -R$(DL) `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(SUN_CC_FLAGS) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)*
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.64sunu b/scripts/makefile.64sunu
index 8880fa9..65414b6 100644
--- a/scripts/makefile.64sunu
+++ b/scripts/makefile.64sunu
@@ -1,38 +1,32 @@
 # makefile for libpng on Solaris 2.x with cc
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
-
+#
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
 # Library name:
 LIBNAME=libpng16
-PNGMAJ = 16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
 CC=cc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -f -s
+AR=ar
 RANLIB=echo
+LN_SF=ln -f -s
 RM_F=/bin/rm -f
 
 SUN_CC_FLAGS=-fast -xtarget=ultra -xarch=v9
 SUN_LD_FLAGS=-fast -xtarget=ultra -xarch=v9
 
-# where make install puts libpng.a, libpng16.so and libpng16/png.h
-prefix=/a
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 # Changing these to ../zlib poses a security risk.  If you want
 # to have zlib in an adjacent directory, specify the full path instead of "..".
@@ -44,34 +38,15 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS= $(SUN_CC_FLAGS) # $(WARNMORE) -g
+CFLAGS=$(SUN_CC_FLAGS) # $(WARNMORE) -g
+ARFLAGS=rc
 LDFLAGS=-L. -R. $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -83,36 +58,16 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -KPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 include scripts/pnglibconf.mak
 DELETE = $(RM_F)
 DFNFLAGS = $(DEFS) $(CPPFLAGS)
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo libdir=\"$(LIBPATH)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-R$(LIBPATH)\"; \
-	echo ccopts=\"-fast -xtarget=ultra -xarch=v9\"; \
-	echo ldopts=\"-fast -xtarget=ultra -xarch=v9\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -138,107 +93,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) $(SUN_CC_FLAGS) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtestd -L$(DL) -R$(DL) `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(SUN_CC_FLAGS) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   $(SUN_LD_FLAGS) -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)*
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.aix b/scripts/makefile.aix
index 5f62d50..5b24f54 100644
--- a/scripts/makefile.aix
+++ b/scripts/makefile.aix
@@ -1,6 +1,6 @@
 # makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2000, 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006-2009, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000 Cosmin Truta
 # Copyright (C) 2000 Marc O. Gloor (AIX support added, from makefile.gcc)
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -15,84 +15,47 @@
 # Compiler, linker, lib and other tools
 CC = gcc
 LD = $(CC)
-AR_RC = ar rcs
-MKDIR_P = mkdir -p
+AR = ar
 RANLIB = ranlib
 RM_F = rm -f
-LN_SF = ln -f -s
 
 LIBNAME = libpng16
 PNGMAJ = 16
 
-prefix=/usr/local
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-
 WARNMORE =
 CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng16 -lz -lm
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS = rc
+LDFLAGS = -L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-all: $(LIBNAME).a pngtest$(E)
+all: $(LIBNAME).a pngtest
 
 include scripts/pnglibconf.mak
 REMOVE = $(RM_F)
 DFNFLAGS = $(DEFS) $(CPPFLAGS)
 
 $(LIBNAME).a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-test: pngtest$(E)
-	./pngtest$(E)
+test: pngtest
+	./pngtest
 
-pngtest$(E): pngtest.o $(LIBNAME).a
+pngtest: pngtest.o $(LIBNAME).a
 	$(LD) -o $@ pngtest.o $(LDFLAGS)
 
-install: $(LIBNAME).a
-	-@if [ ! -d $(DI)  ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME)  ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DI)/$(LIBNAME)/png.h
-	-@$(RM_F) $(DI)/$(LIBNAME)/pngconf.h
-	-@$(RM_F) $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h
-	-@$(RM_F) $(DI)/pngconf.h
-	-@$(RM_F) $(DI)/pnglibconf.h
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h \
-	$(DI)/$(LIBNAME)/pngconf.h \
-	$(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) -r $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
-	-@$(RM_F) $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	cp $(LIBNAME).a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
-	(cd $(DI); $(LN_SF) libpng/* .;)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
 	$(RM_F) *.o $(LIBNAME).a pngtest pngout.png pnglibconf.h
diff --git a/scripts/makefile.amiga b/scripts/makefile.amiga
index 16a4bd5..321c711 100644
--- a/scripts/makefile.amiga
+++ b/scripts/makefile.amiga
@@ -26,16 +26,14 @@
 RM= delete quiet
 # library (.lib) file creation command
 AR= oml
-# make directory command
-MKDIR= makedir
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 all: libpng.lib pngtest
 
diff --git a/scripts/makefile.atari b/scripts/makefile.atari
index b5dbd49..6ed1f79 100644
--- a/scripts/makefile.atari
+++ b/scripts/makefile.atari
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2022 Cosmin Truta
 # Copyright (C) 2002, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -9,35 +10,20 @@
 # Modified for LC56/ATARI assumes libz.lib is in same dir and uses default
 # rules for library management
 #
-CPPFLAGS = -I..\zlib
+CPPFLAGS = -I../zlib
 CFLAGS = -O
 LBR = png.lib
-LDFLAGS = -L. -L..\zlib -lpng -lz -lm
-
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
+LDFLAGS = -L. -L../zlib -lpng -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = $(LBR)(png.o) $(LBR)(pngset.o) $(LBR)(pngget.o) $(LBR)(pngrutil.o)\
-	$(LBR)(pngtrans.o) $(LBR)(pngwutil.o)\
-	$(LBR)(pngread.o) $(LBR)(pngerror.o) $(LBR)(pngwrite.o)\
-	$(LBR)(pngrtran.o) $(LBR)(pngwtran.o)\
-	$(LBR)(pngmem.o) $(LBR)(pngrio.o) $(LBR)(pngwio.o) $(LBR)(pngpread.o)
+OBJS = $(LBR)(png.o) $(LBR)(pngerror.o) $(LBR)(pngget.o) $(LBR)(pngmem.o) \
+       $(LBR)(pngpread.o) $(LBR)(pngread.o) $(LBR)(pngrio.o) \
+       $(LBR)(pngrtran.o) $(LBR)(pngrutil.o) $(LBR)(pngset.o) \
+       $(LBR)(pngtrans.o) $(LBR)(pngwio.o) $(LBR)(pngwrite.o) \
+       $(LBR)(pngwtran.o) $(LBR)(pngwutil.o)
 
 all: $(LBR) pngtest.ttp
 
@@ -54,18 +40,6 @@
 pngtest.ttp: pngtest.o $(LBR)
 	$(CC) $(CFLAGS) $(LDFLAGS) -o$@ pngtest.o
 
-install: libpng.a
-	-@mkdir $(DESTDIR)$(INCPATH)
-	-@mkdir $(DESTDIR)$(INCPATH)/libpng
-	-@mkdir $(DESTDIR)$(LIBPATH)
-	-@rm -f $(DESTDIR)$(INCPATH)/png.h
-	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
-	-@rm -f $(DESTDIR)$(INCPATH)/pnglibconf.h
-	cp png.h $(DESTDIR)$(INCPATH)/libpng
-	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
-	cp pnglibconf.h $(DESTDIR)$(INCPATH)/libpng
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pnglibconf.h
-	(cd $(DESTDIR)$(INCPATH); ln -f -s $(LIBNAME) libpng; \
-	ln -f -s $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
diff --git a/scripts/makefile.bc32 b/scripts/makefile.bc32
index bdbc4cb..7e8f5e1 100644
--- a/scripts/makefile.bc32
+++ b/scripts/makefile.bc32
@@ -50,13 +50,13 @@
 # -M  generate map file
 LDFLAGS=-L$(ZLIB_DIR) -M $(LDEBUG)
 
-# Pre-built configuration
+## Pre-built configuration
 # See scripts\pnglibconf.mak for more options
 !ifndef PNGLIBCONF_H_PREBUILT
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
 !endif
 
-## Variables
+## File lists
 OBJS = \
 	png.obj \
 	pngerror.obj \
@@ -121,22 +121,22 @@
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
-png.obj: png.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.obj:      png.c      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.obj: pngerror.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.obj: pngget.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.obj: pngmem.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.obj:   pngget.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.obj:   pngmem.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.obj: pngpread.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.obj: pngread.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.obj: pngrio.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.obj:  pngread.c  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.obj:   pngrio.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.obj: pngrtran.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.obj: pngrutil.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.obj: pngset.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.obj:   pngset.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.obj: pngtrans.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.obj: pngwio.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.obj:   pngwio.c   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.obj: pngwrite.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.obj: pngwtran.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.obj: pngwutil.c png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtest.obj: pngtest.c png.h pngconf.h pnglibconf.h
+pngtest.obj:  pngtest.c  png.h pngconf.h pnglibconf.h
 
 $(LIBNAME): $(OBJS)
 	-del $(LIBNAME)
diff --git a/scripts/makefile.beos b/scripts/makefile.beos
index 01346f1..fcc7f9c 100644
--- a/scripts/makefile.beos
+++ b/scripts/makefile.beos
@@ -1,5 +1,6 @@
 # makefile for libpng on BeOS x86 ELF with gcc
 # modified from makefile.linux by Sander Stoks
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1999 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -10,20 +11,17 @@
 
 # Library name:
 LIBNAME=libpng16
-PNGMAJ = 16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
 CC=gcc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -sf
 CP=cp
 RM_F=/bin/rm -f
 
@@ -37,45 +35,23 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 
 # On BeOS, -O1 is actually better than -O3.  This is a known bug but it's
 # still here in R4.5
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O1 -funroll-loops $(ALIGN) # $(WARNMORE) -g
+CFLAGS=-O1 -funroll-loops $(ALIGN) -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS=rc
 # LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz
-LDFLAGS=-L. -Wl,-soname=$(LIBSOMAJ) -L$(ZLIBLIB) -lz
-
-# where make install puts libpng.a, libpng16.so*, and png.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
+LDFLAGS=-L. -Wl,-soname=$(LIBSOMAJ) -L$(ZLIBLIB) -lz # -g
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS)
 
@@ -84,37 +60,22 @@
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo libs=\"-lpng16 -lz \"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 	cp $(LIBSO)* /boot/home/config/lib
 
 $(LIBSOMAJ): $(OBJSDLL)
-	$(CC) -nostart -Wl,-soname,$(LIBSOMAJ) -o \
-	$(LIBSOMAJ) $(OBJSDLL) $(LDFLAGS)
+	$(CC) -nostart -Wl,-soname,$(LIBSOMAJ) \
+	 -o $(LIBSOMAJ) $(OBJSDLL) $(LDFLAGS)
 
 pngtest: pngtest.o $(LIBSO)
 	$(CC) -L$(ZLIBLIB) -L. -lz -lpng16 -o pngtest pngtest.o
@@ -122,101 +83,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) $(CFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) -Wl,-rpath $(ZLIBLIB):$(DL) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) $(CFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtesti \
-	pnglibconf.h libpng.pc
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.cegcc b/scripts/makefile.cegcc
deleted file mode 100644
index 6f915c2..0000000
--- a/scripts/makefile.cegcc
+++ /dev/null
@@ -1,116 +0,0 @@
-# Makefile for creating Windows CE release archives, with the
-# mingw32ce compiler.
-
-# Last updated: 22-Jul-2008
-
-# Copyright (C) 2008 Vincent Torri
-
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# To get some help, type
-#
-# make help
-#
-# To create the archives
-#
-# make
-#
-# To remove everything, type:
-#
-# make clean
-
-VERMAJ = 1
-VERMIN = 6
-VERMIC = 37
-VER = $(VERMAJ).$(VERMIN).$(VERMIC)
-NAME = libpng
-PACKAGE = $(NAME)-$(VER)
-
-BIN = libpng16-0.dll
-LIB = libpng16.a libpng16.dll.a libpng.a libpng.dll.a
-INCLUDE = png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-PC = libpng16.pc libpng.pc
-
-MANIFESTVERBIN = "Libpng-$(VER): Binary files"
-MANIFESTVERDEV = "Libpng-$(VER): Developer files"
-MANIFESTVERDESC = "Libpng: the official PNG reference library"
-
-all: $(NAME)
-
-$(NAME): remove-old copy-src compilation copy manifest archive
-	@echo " * Removal of the directories"
-	@rm -rf $(PACKAGE)/ $(PACKAGE)-bin/ $(PACKAGE)-dev/
-
-remove-old:
-	@echo " * Removal of the old files"
-	@rm -rf $(PACKAGE)-bin*
-	@rm -rf $(PACKAGE)-dev*
-
-copy-src:
-	@echo " * Copy of source files"
-	@cp -R ../src/$(PACKAGE) .
-	@echo " * Creation of directories and files"
-	@mkdir -p $(PACKAGE)-bin/bin
-	@mkdir -p $(PACKAGE)-bin/manifest
-	@mkdir -p $(PACKAGE)-dev/lib/pkgconfig
-	@mkdir -p $(PACKAGE)-dev/include/$(NAME)$(VERMAJ)$(VERMIN)
-	@mkdir -p $(PACKAGE)-dev/manifest
-	@touch $(PACKAGE)-bin/manifest/$(PACKAGE)-bin.mft
-	@touch $(PACKAGE)-bin/manifest/$(PACKAGE)-bin.ver
-	@touch $(PACKAGE)-dev/manifest/$(PACKAGE)-dev.mft
-	@touch $(PACKAGE)-dev/manifest/$(PACKAGE)-dev.ver
-
-compilation:
-	@echo " * Compilation of $(PACKAGE)"
-	cd $(PACKAGE) && CPPFLAGS="$(CPPFLAGS) -DPNG_CONSOLE_IO_SUPPORTED -D_WIN32_WCE=0x0420" \
-		CFLAGS="$(CFLAGS) -mms-bitfields -O3 -pipe -fomit-frame-pointer" \
-		LDFLAGS="$(LDFLAGS) -Wl,--enable-auto-import -Wl,-s" \
-		./configure --prefix=/opt/wince --host=arm-mingw32ce && make
-
-copy:
-	@echo " * Copy of binary and development files"
-	@for i in $(BIN); do \
-	  cp $(PACKAGE)/.libs/$$i $(PACKAGE)-bin/bin; \
-	done
-	@for i in $(LIB); do \
-	  cp $(PACKAGE)/.libs/$$i $(PACKAGE)-dev/lib; \
-	done
-	@for i in $(INCLUDE); do \
-	  cp $(PACKAGE)/$$i $(PACKAGE)-dev/include/$(NAME)$(VERMAJ)$(VERMIN); \
-	done
-	@for i in $(PC); do \
-	  cp $(PACKAGE)/$$i $(PACKAGE)-dev/lib/pkgconfig; \
-	done
-
-manifest:
-	@echo " * Creation of the manifest"
-	@cd $(PACKAGE)-bin && find * >> manifest/$(PACKAGE)-bin.mft
-	@cd $(PACKAGE)-bin && \
-	  echo $(MANIFESTVERBIN) >> manifest/$(PACKAGE)-bin.ver && \
-	  echo $(MANIFESTVERDESC) >> manifest/$(PACKAGE)-bin.ver
-	@cd $(PACKAGE)-dev && find * >> manifest/$(PACKAGE)-dev.mft
-	@cd $(PACKAGE)-dev && \
-	  echo $(MANIFESTVERDEV) >> manifest/$(PACKAGE)-dev.ver && \
-	  echo $(MANIFESTVERDESC) >> manifest/$(PACKAGE)-dev.ver
-
-archive:
-	@echo " * Creation of the archives"
-	@tar cf $(PACKAGE)-bin.tar $(PACKAGE)-bin
-	@bzip2 -9 $(PACKAGE)-bin.tar
-	@tar cf $(PACKAGE)-dev.tar $(PACKAGE)-dev
-	@bzip2 -9 $(PACKAGE)-dev.tar
-
-clean:
-	@echo " * Cleaning"
-	@rm -rf $(PACKAGE)*
-
-help:
-	@echo
-	@echo "To create the archives, type:"
-	@echo " make"
-	@echo
-	@echo "To remove everything, type:"
-	@echo " make clean"
-	@echo
diff --git a/scripts/makefile.clang b/scripts/makefile.clang
index fcaefae..08aaccf 100644
--- a/scripts/makefile.clang
+++ b/scripts/makefile.clang
@@ -1,6 +1,6 @@
 # makefile for libpng using clang (generic, static library)
+# Copyright (C) 2000, 2014, 2019-2024 Cosmin Truta
 # Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
@@ -14,17 +14,22 @@
 # Compiler, linker, lib and other tools
 CC = clang
 LD = $(CC)
-AR_RC = ar rcs
+AR = ar
 RANLIB = ranlib
 CP = cp
 RM_F = rm -f
 
+# Compiler and linker flags
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
 	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L$(ZLIBLIB)
+DEFS = $(NOHWOPT)
+CPPFLAGS = -I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS = rc
+LDFLAGS = -L$(ZLIBLIB) # -g
 LIBS = -lz -lm
 
 # File extensions
@@ -34,10 +39,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static
@@ -56,7 +61,7 @@
 	@false
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 test: pngtest$(EXEEXT)
diff --git a/scripts/makefile.darwin b/scripts/makefile.darwin
index 33c27cc..e68797e 100644
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -1,4 +1,5 @@
-# makefile for libpng on Darwin / Mac OS X
+# makefile for libpng on Darwin / macOS
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2004, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 2001 Christoph Pfisterer
 # derived from makefile.linux:
@@ -9,66 +10,42 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where "make install" puts libpng.a, libpng16.dylib, png.h, pngconf.h,
-# and pnglibconf.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 ZLIBLIB=/usr/lib
 ZLIBINC=/usr/include
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).dylib
 LIBSOMAJ=$(LIBNAME).$(PNGMAJ).dylib
-LIBSOREL=$(LIBNAME).$(PNGMAJ).$(RELEASE).dylib
-OLDSO=libpng.dylib
 
 # Utilities:
 CC=cc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -sf
 CP=cp
-RM_F=/bin/rm -f
+RM_F=rm -f
 
-CPPFLAGS=-I$(ZLIBINC)
-# CFLAGS=-W -Wall -O3 -funroll-loops
-CFLAGS=-W -Wall -O -funroll-loops
+NOHWOPT=-DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+        -DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
+DEFS=$(NOHWOPT)
+CPPFLAGS=-I$(ZLIBINC) $(DEFS)
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef
+ARFLAGS=rc
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -80,37 +57,20 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fno-common -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
 $(LIBSOMAJ): $(OBJSDLL)
 	$(CC) -dynamiclib \
-	 -install_name $(LIBPATH)/$(LIBSOMAJ) \
 	 -current_version 16 -compatibility_version 16 \
 	 -o $(LIBSOMAJ) \
 	 $(OBJSDLL) -L$(ZLIBLIB) -lz
@@ -121,105 +81,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	$(RANLIB) $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOMAJ)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)
-	chmod 755 $(DL)/$(LIBSOMAJ)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) $(CFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	libpng.pc $(LIBNAME).*dylib pngtesti pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBNAME).*dylib pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.dec b/scripts/makefile.dec
index 8566a02..2cca020 100644
--- a/scripts/makefile.dec
+++ b/scripts/makefile.dec
@@ -1,4 +1,5 @@
 # makefile for libpng on DEC Alpha Unix
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2000-2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -7,47 +8,21 @@
 # and license in png.h
 
 # Library name:
-PNGMAJ = 16
-LIBNAME = libpng16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
-MKDIR_P=mkdir
-LN_SF=ln -f -s
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -f -s
 CP=cp
 RM_F=/bin/rm -f
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib
 #ZLIBINC=/usr/local/include
@@ -56,51 +31,34 @@
 
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS=-std -w1 -O # -g
+ARFLAGS=rc
 LDFLAGS=-L$(ZLIBLIB) -rpath $(ZLIBLIB) libpng.a -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-all: $(LIBSO) libpng.a pngtest libpng.pc libpng-config
+all: $(LIBSO) libpng.a pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"-std\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
 $(LIBSOMAJ): $(OBJS)
-	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) \
-	-soname $(LIBSOMAJ)
+	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) -soname $(LIBSOMAJ)
 
 pngtest: pngtest.o libpng.a
 	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
@@ -108,103 +66,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@/bin/rm -f $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@/bin/rm -f $(DI)/libpng
-	(cd $(DI); $(LN_SF)(LIBNAME) libpng; $(LN_SF)(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@/bin/rm -f $(DL)/libpng.a
-	(cd $(DL); $(LN_SF)(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@/bin/rm -f $(DM)/man3/libpng.3
-	-@/bin/rm -f $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@/bin/rm -f $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@/bin/rm -f $(DB)/libpng-config
-	-@/bin/rm -f $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF)(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -w1 -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB)  -R$(ZLIBLIB) -R$(DL) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) -w1 $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -R$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.dj2 b/scripts/makefile.dj2
index e59c432..3767150 100644
--- a/scripts/makefile.dj2
+++ b/scripts/makefile.dj2
@@ -1,4 +1,5 @@
 # DJGPP (DOS gcc) makefile for libpng
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2009-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -6,19 +7,14 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where make install will put libpng.a and png.h
-#prefix=/usr/local
-prefix=.
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
 CC=gcc
+AR=ar
+RANLIB=ranlib
 CPPFLAGS=-I../zlib -DPNG_NO_SNPRINTF
 CFLAGS=-O
+ARFLAGS=rc
 LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
 
-RANLIB=ranlib
-
 CP=cp
 RM_F=rm -f
 
@@ -26,9 +22,9 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o pngwtran.o \
-	pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -39,7 +35,7 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	ar rc $@  $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
@@ -48,19 +44,24 @@
 
 test: pngtest
 	./pngtest
+
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
+
 clean:
 	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
@@ -69,4 +70,4 @@
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.emcc b/scripts/makefile.emcc
new file mode 100644
index 0000000..1ab01b8
--- /dev/null
+++ b/scripts/makefile.emcc
@@ -0,0 +1,84 @@
+# makefile for libpng using emscripten
+# Copyright (C) 2000, 2014, 2019-2024 Cosmin Truta
+# Copyright (C) 2021 Kirk Roerig
+# Copyright (C) 2008, 2014 Glenn Randers-Pehrson
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+
+# Location of the zlib library and include files
+ZLIBINC = ../zlib
+ZLIBLIB = ../zlib
+
+# Compiler, linker, lib and other tools
+CC = emcc
+LD = $(CC)
+AR = emar
+RANLIB = emranlib
+CP = cp
+RM_F = rm -f
+
+CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
+CFLAGS = -O2 -Wall -Wextra -Wundef
+ARFLAGS = rc
+LDFLAGS = -L$(ZLIBLIB)
+PNGTEST_LDFLAGS = --preload-file=pngtest.png
+LIBS = -lz -lm
+
+# Pre-built configuration
+# See scripts/pnglibconf.mak for more options
+PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
+
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+
+# Targets
+all: static
+
+pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
+	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
+
+.c.o:
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+
+static: libpng.a pngtest
+
+shared:
+	@echo This makefile cannot create shared libraries.
+	@false
+
+libpng.a: $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+	$(RANLIB) $@
+
+test: pngtest
+	node ./pngtest
+
+pngtest: pngtest.o libpng.a
+	$(LD) $(LDFLAGS) $(PNGTEST_LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
+
+clean:
+	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
+	$(RM_F) pngtest.data pngtest.wasm
+
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.freebsd b/scripts/makefile.freebsd
index 5fec61e..e4e96a1 100644
--- a/scripts/makefile.freebsd
+++ b/scripts/makefile.freebsd
@@ -1,4 +1,5 @@
 # makefile for libpng under FreeBSD
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2014 Glenn Randers-Pehrson and Andrey A. Chernov
 # Copyright (C) 2002, 2007, 2009 Glenn Randers-Pehrson and Andrey A. Chernov
 #
@@ -6,28 +7,11 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-PREFIX?=        /usr/local
-SHLIB_VER?=     16
-
 LIB=		png
+SHLIB_VER=	16
 SHLIB_MAJOR=	${SHLIB_VER}
 SHLIB_MINOR=	0
-NO_PROFILE=	YES
-NO_OBJ=		YES
 
-# where make install puts libpng.a and png.h
-DESTDIR=	${PREFIX}
-LIBDIR=		/lib
-INCS=		png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-INCSDIR=	/include/libpng
-INCDIR=		${INCSDIR}		# for 4.x bsd.lib.mk
-MAN=		libpng.3 libpngpf.3 png.5
-MANDIR=		/man/man
-SYMLINKS=       libpng/png.h ${INCSDIR}/../png.h \
-		libpng/pngconf.h ${INCSDIR}/../pngconf.h \
-		libpng/pnglibconf.h ${INCSDIR}/../pnglibconf.h
-
-# where make install finds libz.a and zlib.h
 ZLIBLIB=	/usr/lib
 ZLIBINC=	/usr/include
 
@@ -37,33 +21,33 @@
 DPADD+=		${LIBM} ${LIBZ}
 
 CPPFLAGS+=	-I. -I${ZLIBINC}
-CFLAGS+=	-W -Wall
+CFLAGS+=	-Wall -Wextra -Wundef
+LDFLAGS+=	-L. -L${ZLIBLIB}
+
+CLEANFILES+=	pngtest pngtest.o pngout.png
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT= scripts/pnglibconf.h.prebuilt
 
-SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
-	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
-	pngwtran.c pngmem.c pngerror.c pngpread.c
+SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 
 .c.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
+	${CC} -c ${CPPFLAGS} ${CFLAGS} -o $@ $<
 
-pngtest: pngtest.o libpng.a
-	${CC} ${CFLAGS} -L. -static -o pngtest pngtest.o -L${ZLIBLIB} \
-	-lpng ${LDADD}
+pnglibconf.h:	${PNGLIBCONF_H_PREBUILT}
+	cp ${PNGLIBCONF_H_PREBUILT} $@
 
-CLEANFILES= pngtest pngtest.o pngout.png
+pngtest:	pngtest.o libpng.a
+	${CC} ${LDFLAGS} -static -o pngtest pngtest.o -lpng ${LDADD}
 
-test: pngtest
+test:	pngtest
 	./pngtest
 
-pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
-	cp $(PNGLIBCONF_H_PREBUILT) $@
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 .include <bsd.lib.mk>
diff --git a/scripts/makefile.gcc b/scripts/makefile.gcc
index a977313..fc0a1a0 100644
--- a/scripts/makefile.gcc
+++ b/scripts/makefile.gcc
@@ -1,6 +1,6 @@
 # makefile for libpng using gcc (generic, static library)
+# Copyright (C) 2000, 2014, 2019-2024 Cosmin Truta
 # Copyright (C) 2008, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000, 2014, 2019 Cosmin Truta
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
 # This code is released under the libpng license.
@@ -14,17 +14,22 @@
 # Compiler, linker, lib and other tools
 CC = gcc
 LD = $(CC)
-AR_RC = ar rcs
+AR = ar
 RANLIB = ranlib
 CP = cp
 RM_F = rm -f
 
+# Compiler and linker flags
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE = -Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
 	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 # $(WARNMORE) -g
-LDFLAGS = -L$(ZLIBLIB)
+DEFS = $(NOHWOPT)
+CPPFLAGS = -I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS = -O2 -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS = rc
+LDFLAGS = -L$(ZLIBLIB) # -g
 LIBS = -lz -lm
 
 # File extensions
@@ -34,10 +39,10 @@
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static
@@ -56,7 +61,7 @@
 	@false
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 test: pngtest$(EXEEXT)
diff --git a/scripts/makefile.hp64 b/scripts/makefile.hp64
index 4421e78..c974d2f 100644
--- a/scripts/makefile.hp64
+++ b/scripts/makefile.hp64
@@ -1,4 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 1999-2002, 2006, 2009, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # Contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
@@ -19,21 +20,18 @@
 #   SHAREDLIB=libz.sl
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
 LIBSOMAJ=$(LIBNAME).sl.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.sl
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -sf
 CP=cp
 RM_F=/bin/rm -f
 
@@ -42,39 +40,16 @@
 CFLAGS=-O -Ae -Wl,+vnocompatwarnings +DD64 +Z
 # Caution: be sure you have built zlib with the same CFLAGS.
 CCFLAGS=-O -Ae -Wl,+vnocompatwarnings +DD64 +Z
-
+ARFLAGS=rc
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
 
-# where make install puts libpng.a, libpng16.sl, and png.h
-prefix=/opt/libpng
-exec_prefix=$(prefix)
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -86,32 +61,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) +z -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"-O -Ae -Wl,+vnocompatwarnings +DD64 +Z\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -125,107 +83,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) $(CCFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) $(CCFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.hpgcc b/scripts/makefile.hpgcc
index efef1f3..a24fb93 100644
--- a/scripts/makefile.hpgcc
+++ b/scripts/makefile.hpgcc
@@ -1,4 +1,5 @@
 # makefile for libpng on HP-UX using GCC with the HP ANSI/C linker.
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006-2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 2001, Laurent faillie
 # Copyright (C) 1998, 1999 Greg Roelofs
@@ -9,30 +10,22 @@
 # and license in png.h
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
 LIBSOMAJ=$(LIBNAME).sl.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.sl
 
 # Utilities:
 CC=gcc
-LD=ld
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LD=ld
+LN_SF=ln -sf
 CP=cp
 RM_F=/bin/rm -f
 
-# where "make install" puts libpng.a, $(OLDSO)*, png.h, pngconf.h
-# and pnglibconf.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 ZLIBLIB=/opt/zlib/lib
 ZLIBINC=/opt/zlib/include
@@ -44,44 +37,19 @@
 #   LDSHARED=ld -b
 #   SHAREDLIB=libz.sl
 
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O3 -funroll-loops $(ALIGN) # $(WARNMORE) -g
-#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS=rc
+#LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -93,27 +61,12 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -127,108 +80,38 @@
 test: pngtest
 	./pngtest
 
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
-
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) -Wl,-rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.hpux b/scripts/makefile.hpux
index 27b312a..c3950ae 100644
--- a/scripts/makefile.hpux
+++ b/scripts/makefile.hpux
@@ -1,4 +1,5 @@
 # makefile for libpng, HPUX (10.20 and 11.00) using the ANSI/C product.
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 1999-2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42
 # Contributed by Jim Rice and updated by Chris Schleicher, Hewlett Packard
@@ -20,59 +21,34 @@
 #   SHAREDLIB=libz.sl
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).sl
 LIBSOMAJ=$(LIBNAME).sl.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.sl
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -sf
 RM_F=/bin/rm -f
 
-# where make install puts libpng.a, libpng16.sl, and png.h
-prefix=/opt/libpng
-exec_prefix=$(prefix)
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
 CPPFLAGS=-I$(ZLIBINC)
 CFLAGS=-O -Ae +DA1.1 +DS2.0
 # Caution: be sure you have built zlib with the same CFLAGS.
 CCFLAGS=-O -Ae +DA1.1 +DS2.0
+ARFLAGS=rc
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
 
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -84,32 +60,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) +z -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"-O -Ae +DA1.1 +DS2.0\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -123,107 +82,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) $(CCFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) $(CCFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.ibmc b/scripts/makefile.ibmc
index 89b1196..95cd0d8 100644
--- a/scripts/makefile.ibmc
+++ b/scripts/makefile.ibmc
@@ -1,7 +1,7 @@
 # Makefile for libpng (static)
 # IBM C version 3.x for Win32 and OS/2
 # Copyright (C) 2006, 2014 Glenn Randers-Pehrson
-# Copyright (C) 2000 Cosmin Truta
+# Copyright (C) 2000, 2020 Cosmin Truta
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -37,10 +37,10 @@
 A=.lib
 E=.exe
 
-# Variables
+# File lists
 OBJS = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O) \
-	pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
-	pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+       pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O) \
+       pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
 
 LIBS = libpng$(A) $(ZLIBLIB)/zlib$(A)
 
@@ -65,11 +65,11 @@
 	$(LD) $(LDFLAGS) pngtest$(O) $(LIBS)
 
 clean:
-	$(RM) *$(O)
-	$(RM) libpng$(A)
-	$(RM) pnglibconf.h
-	$(RM) pngtest$(E)
-	$(RM) pngout.png
+	-$(RM) *$(O)
+	-$(RM) libpng$(A)
+	-$(RM) pnglibconf.h
+	-$(RM) pngtest$(E)
+	-$(RM) pngout.png
 
 png$(O):      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
diff --git a/scripts/makefile.intel b/scripts/makefile.intel
index 4187261..d996011 100644
--- a/scripts/makefile.intel
+++ b/scripts/makefile.intel
@@ -31,7 +31,7 @@
 
 # --------------------------------------------------------------------------
 
-CC=icl -c
+CC=icl
 CPPFLAGS=-I$(ZLIBINC)
 CFLAGS=-O2 -G$(CPU)$(CALLING) -Qip -Qunroll4 -nologo
 LD=link
@@ -42,61 +42,65 @@
 # See scripts\pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
 
+# File extensions
 O=.obj
 
-OBJS=png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O) \
-pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O) \
-pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+# File lists
+OBJS1=png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2=pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3=pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS=$(OBJS1) $(OBJS2) $(OBJS3)
 
+# Targets
 all: test
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngwutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 libpng.lib: $(OBJS)
 	if exist libpng.lib del libpng.lib
@@ -106,10 +110,9 @@
 	$(LD) $(LDFLAGS) /OUT:pngtest.exe pngtest.obj libpng.lib $(ZLIBLIB)\zlib.lib
 
 pngtest$(O): png.h pngconf.h pnglibconf.h
-	$(CC) $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 test: pngtest.exe
 	pngtest.exe
 
-
 # End of makefile for libpng
diff --git a/scripts/makefile.linux b/scripts/makefile.linux
index f2d8bea..c49cdde 100644
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so on Linux ELF with gcc
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 1998, 1999, 2002, 2006, 2008, 2010-2014 Greg Roelofs and
 # Glenn Randers-Pehrson
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -8,30 +9,20 @@
 # and license in png.h
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
-RELEASE = 37
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=ranlib
+LN_SF=ln -sf
 CP=cp
-RM_F=/bin/rm -f
-
-# where "make install" puts libpng16.a, libpng16.so*,
-# libpng16/png.h, libpng16/pngconf.h, and libpng16/pnglibconf.h
-# Prefix must be a full pathname.
-prefix=/usr/local
-exec_prefix=$(prefix)
+RM_F=rm -f
 
 # Where the zlib library and include files are located.
 #ZLIBLIB=/usr/local/lib
@@ -39,49 +30,27 @@
 ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
+# Compiler and linker flags
+NOHWOPT=-DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
-
-CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O3 -funroll-loops $(ALIGN) # $(WARNMORE) -g
-
-LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
-
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
+DEFS=$(NOHWOPT)
+CPPFLAGS=-I$(ZLIBINC) $(DEFS) # -DPNG_DEBUG=5
+CFLAGS=-O3 -funroll-loops -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS=rc
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm # -g
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -93,32 +62,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest pngtest-static libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest pngtest-static
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -141,106 +93,39 @@
 	@echo ""
 	./pngtest-static
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) -Wl, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) $(OBJS) $(OBJSDLL) libpng.a
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
+	$(RM_F) pngtest*.o pngtest pngtest-static pngout.png
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.linux-opt b/scripts/makefile.linux-opt
deleted file mode 100644
index 327151f..0000000
--- a/scripts/makefile.linux-opt
+++ /dev/null
@@ -1,265 +0,0 @@
-# makefile for libpng.a and libpng16.so on Linux ELF with gcc
-# Copyright (C) 1998,1999,2002,2006,2008,2010-2014,2017 Greg Roelofs and
-# Glenn Randers-Pehrson
-# Copyright (C) 1996,1997 Andreas Dilger
-#
-# This code is released under the libpng license.
-# For conditions of distribution and use, see the disclaimer
-# and license in png.h
-
-# Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
-RELEASE = 37
-
-# Shared library names:
-LIBSO=$(LIBNAME).so
-LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
-
-# Utilities:
-AR_RC=ar rc
-CC=gcc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
-RANLIB=ranlib
-CP=cp
-RM_F=/bin/rm -f
-
-# where "make install" puts libpng16.a, libpng16.so*,
-# libpng16/png.h, libpng16/pngconf.h, and libpng16/pnglibconf.h
-# Prefix must be a full pathname.
-prefix=/usr/local
-exec_prefix=$(prefix)
-
-# Where the zlib library and include files are located.
-#ZLIBLIB=/usr/local/lib
-#ZLIBINC=/usr/local/include
-ZLIBLIB=../zlib
-ZLIBINC=../zlib
-
-ALIGN=
-# for i386:
-#ALIGN=-malign-loops=2 -malign-functions=2
-
-#WARNMORE=-Wwrite-strings -Wpointer-arith \
-#	-Wmissing-declarations -Wtraditional -Wcast-align \
-#	-Wstrict-prototypes -Wmissing-prototypes
-
-# for pgcc version 2.95.1, -O3 is buggy; don't use it.
-
-CPPFLAGS=-I$(ZLIBINC)
-CPPFLAGS += -DPNG_ARM_NEON
-CPPFLAGS += -DPNG_MIPS_MSA
-CPPFLAGS += -DPNG_INTEL_SSE
-CPPFLAGS += -DPNG_POWERPC_VSX
-CPPFLAGS+=-ansi -pedantic -Wextra -Wall -Wshadow -Wno-sign-conversion
-CPPFLAGS+=-W -Wall -Wconversion $(ALIGN)
-# CPPFLAGS+=$(WARNMORE)
-CFLAGS= -O3 -funroll-loops
-
-LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS_A=-L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) libpng.a -lz -lm
-
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
-# Pre-built configuration
-# See scripts/pnglibconf.mak for more options
-PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
-
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o \
-	arm/arm_init.o arm/filter_neon_intrinsics.o \
-	mips/mips_init.o mips/filter_msa_intrinsics.o \
-	intel/intel_init.o intel/filter_sse2_intrinsics.o\
-	powerpc/powerpc_init.o powerpc/filter_vsx_intrinsics.o
-
-OBJSDLL = $(OBJS:.o=.pic.o)
-
-.SUFFIXES:      .c .o .pic.o
-
-.c.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
-
-.c.pic.o:
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fPIC -o $@ $*.c
-
-all: libpng.a $(LIBSO) pngtest pngtest-static libpng.pc libpng-config
-
-pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
-	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
-
-libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
-	$(RANLIB) $@
-
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
-$(LIBSO): $(LIBSOMAJ)
-	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
-
-$(LIBSOMAJ): $(OBJSDLL)
-	$(CC) -shared -Wl,-soname,$(LIBSOMAJ) -o $(LIBSOMAJ) $(OBJSDLL)
-
-pngtest: pngtest.o $(LIBSO)
-	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
-
-pngtest-static: pngtest.o libpng.a
-	$(CC) -o pngtest-static $(CFLAGS) pngtest.o $(LDFLAGS_A)
-
-test: pngtest pngtest-static
-	@echo ""
-	@echo "   Running pngtest dynamically linked with $(LIBSO):"
-	@echo ""
-	./pngtest
-	@echo ""
-	@echo "   Running pngtest statically linked with libpng.a:"
-	@echo ""
-	./pngtest-static
-
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
-
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
-
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) -Wl, -rpath,$(DL) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
-
-clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
-# DO NOT DELETE THIS LINE -- make depend depends on it.
-
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-arm/arm_init.o arm/arm_init.o: pngpriv.h
-arm/filter_neon_intrinsics.o arm/filter_neon_intrinsics.pic.o: pngpriv.h
-mips/mips_init.o mips/mips_init.pic.o: pngpriv.h
-mips/filter_msa_intrinsics.o mips/filter_msa_intrinsics.pic.:  pngpriv.h
-intel/intel_init.o intel/intel_init.pic.:  pngpriv.h
-intel/filter_sse2_intrinsics.o intel/filter_sse2_intrinsics.pic.:  pngpriv.h
-powerpc/powerpc_init.o powerpc/powerpc_init.pic.:  pngpriv.h
-powerpc/filter_vsx_intrinsics.o powerpc/filter_vsx_intrinsics.pic.:  pngpriv.h
-
-pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.mips b/scripts/makefile.mips
index 0357ae8..45de36d 100644
--- a/scripts/makefile.mips
+++ b/scripts/makefile.mips
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 1998-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -6,39 +7,23 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
 CC=cc
+AR=ar
+#RANLIB=ranlib
+RANLIB=echo
 CPPFLAGS=-I../zlib -DSYSV -Dmips
 CFLAGS=-O -systype sysv -w
 #CFLAGS=-O
+ARFLAGS=rc
 LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
 
-#RANLIB=ranlib
-RANLIB=echo
-
-CP=cp
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -46,10 +31,10 @@
 all: libpng.a pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
-	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
+	cp $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	ar rc $@  $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
@@ -58,46 +43,29 @@
 test: pngtest
 	./pngtest
 
-install: libpng.a
-	-@mkdir $(DESTDIR)$(INCPATH)
-	-@mkdir $(DESTDIR)$(INCPATH)/libpng
-	-@mkdir $(DESTDIR)$(LIBPATH)
-	-@rm -f $(DESTDIR)$(INCPATH)/png.h
-	-@rm -f $(DESTDIR)$(INCPATH)/pngconf.h
-	-@rm -f $(DESTDIR)$(INCPATH)/pnglibconf.h
-	cp png.h $(DESTDIR)$(INCPATH)/libpng
-	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
-	cp pnglibconf.h $(DESTDIR)$(INCPATH)/libpng
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pnglibconf.h
-	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
-	cp libpng.a $(DESTDIR)$(LIBPATH)
-	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
 	rm -f *.o libpng.a pngtest pngout.png pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.msys b/scripts/makefile.msys
index 6b9daf8..8ebcaab 100644
--- a/scripts/makefile.msys
+++ b/scripts/makefile.msys
@@ -1,5 +1,5 @@
 # makefile for libpng using MSYS/gcc (shared, static library)
-# Copyright (C) 2019 Cosmin Truta
+# Copyright (C) 2000, 2019-2024 Cosmin Truta
 # Copyright (C) 2012 Glenn Randers-Pehrson and Christopher M. Wheeler
 #
 # Portions taken from makefile.linux and makefile.gcc:
@@ -12,20 +12,14 @@
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
-# # # # # # # # # # # # # # # # #
-prefix=/usr/local
-exec_prefix=$(prefix)
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
-RELEASE = 37
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).dll
 LIBSOMAJ=$(LIBNAME).dll.$(PNGMAJ)
-LIBSOREL=$(PNGMAJ).$(RELEASE)
-OLDSO=libpng.dll
 
 # Where the zlib library and include files are located.
 #ZLIBLIB=../zlib
@@ -36,53 +30,29 @@
 # Compiler, linker, lib and other tools
 CC = gcc
 LD = $(CC)
-AR_RC = ar rcs
+AR = ar
 RANLIB = ranlib
 CP = cp
 RM_F = rm -rf
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+LN_SF = ln -sf
 
-#ARCH = -march=pentium3
-#ARCH = -march=i686
-ARCH =
 CPPFLAGS = # -DPNG_DEBUG=5
-CFLAGS = -W -Wall -O2 $(ARCH) # -g
-LDFLAGS =
+CFLAGS = -O2 -Wall -Wextra -Wundef # -g
+ARFLAGS = rc
+LDFLAGS = # -g
 LIBS = -lz -lm
 
 # File extensions
-EXEEXT=.exe
-
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
+EXEEXT = .exe
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-# Variables
-OBJS =  png.o pngerror.o pngget.o pngmem.o pngpread.o \
-	pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
-	pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
+# File lists
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 # Targets
 all: static shared
@@ -105,73 +75,20 @@
 	$(CC) -shared -Wl,-soname,$(LIBSOMAJ) -o $(LIBSOMAJ)
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-Wl,-rpath,$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSO) $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 test: pngtest$(EXEEXT)
 	./pngtest$(EXEEXT)
@@ -180,8 +97,9 @@
 	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 clean:
-	$(RM_F) *.o libpng.a pngtest$(EXEEXT) pngout.png pnglibconf.h $(LIBSO) \
-	$(LIBSOMAJ) libpng-config
+	$(RM_F) $(OBJS) libpng.a
+	$(RM_F) $(LIBSO) $(LIBSOMAJ) pnglibconf.h
+	$(RM_F) pngtest*.o pngtest$(EXEEXT) pngout.png
 
 png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
diff --git a/scripts/makefile.netbsd b/scripts/makefile.netbsd
index 5802f31..d3419f2 100644
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -1,29 +1,25 @@
-# makefile for libpng for NetBSD for the standard
-# make obj && make depend && make && make test
-# make includes && make install
-# Copyright (C) 2002 Patrick R.L. Welche
+# makefile for libpng on NetBSD
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2007-2009, 2014 Glenn Randers-Pehrson
+# Copyright (C) 2002 Patrick R.L. Welche
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-LOCALBASE?=/usr/local
-LIBDIR=	${LOCALBASE}/lib
-MANDIR= ${LOCALBASE}/man
-INCSDIR=${LOCALBASE}/include
-
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.38.git
+SHLIB_MINOR=	0
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
-	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c pngtrans.c \
-	pngwio.c pngwrite.c pngwtran.c pngwutil.c
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 INCS=	png.h pngconf.h pnglibconf.h
-MAN=	libpng.3 libpngpf.3 png.5
 
-CPPFLAGS+=-I${.CURDIR}
+CPPFLAGS+=	-I${.CURDIR}
+CFLAGS+=	-Wall -Wextra -Wundef
+
+CLEANFILES+=	pngtest.o pngtest pnglibconf.h
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
@@ -35,12 +31,10 @@
 #   MKLINT= no
 # .endif
 
-CLEANFILES+=pngtest.o pngtest pnglibconf.h
-
 .c.o:
 	${CC} -c ${CPPFLAGS} ${CFLAGS} -o $@ $<
 
-pnglibconf.h: ${PNGLIBCONF_H_PREBUILT}
+pnglibconf.h:	${PNGLIBCONF_H_PREBUILT}
 	cp ${PNGLIBCONF_H_PREBUILT} $@
 
 pngtest.o:	pngtest.c
@@ -50,6 +44,10 @@
 	${CC} ${LDFLAGS} ${.ALLSRC} -o ${.TARGET} -lz -lm
 
 test:	pngtest
-	cd ${.CURDIR} && ${.OBJDIR}/pngtest
+	./pngtest
+
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 .include <bsd.lib.mk>
diff --git a/scripts/makefile.openbsd b/scripts/makefile.openbsd
index b3aec33..6bfeab7 100644
--- a/scripts/makefile.openbsd
+++ b/scripts/makefile.openbsd
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2022 Cosmin Truta
 # Copyright (C) 2007-2009, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -6,28 +7,19 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-PREFIX?= /usr/local
-LIBDIR=	${PREFIX}/lib
-MANDIR= ${PREFIX}/man/cat
-
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.38.git
+SHLIB_MINOR=	0
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
-	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c pngtrans.c \
-	pngwio.c pngwrite.c pngwtran.c pngwutil.c
+	pngread.c pngrio.c pngrtran.c pngrutil.c pngset.c \
+	pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c
 HDRS=	png.h pngconf.h pnglibconf.h
-MAN=	libpng.3 libpngpf.3 png.5
-DOCS=	ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO \
-	libpng-manual.txt
 
-CFLAGS+= -W -Wall
-CPPFLAGS+= -I${.CURDIR}
+CPPFLAGS+=	-I${.CURDIR}
+CFLAGS+=	-Wall -Wextra -Wundef
 
-NOPROFILE= Yes
-
-CLEANFILES+= pngtest.o pngtest pnglibconf.h
+CLEANFILES+=	pngtest.o pngtest pnglibconf.h
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
@@ -36,7 +28,7 @@
 .c.o:
 	${CC} -c ${CPPFLAGS} ${CFLAGS} -o $@ $<
 
-pnglibconf.h: ${PNGLIBCONF_H_PREBUILT}
+pnglibconf.h:	${PNGLIBCONF_H_PREBUILT}
 	cp ${PNGLIBCONF_H_PREBUILT} $@
 
 pngtest.o:	pngtest.c
@@ -46,41 +38,10 @@
 	${CC} ${LDFLAGS} ${.ALLSRC} -o ${.TARGET} -L${.OBJDIR} -lpng -lz -lm
 
 test:	pngtest
-	cd ${.OBJDIR} && env \
-		LD_LIBRARY_PATH="${.OBJDIR}" ${.OBJDIR}/pngtest
+	env LD_LIBRARY_PATH="${.OBJDIR}" ./pngtest
 
-beforeinstall:
-	if [ ! -d ${DESTDIR}${PREFIX}/include/libpng ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${PREFIX}/include; \
-	fi
-	if [ ! -d ${DESTDIR}${LIBDIR} ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${LIBDIR}; \
-	fi
-	if [ ! -d ${DESTDIR}${LIBDIR}/debug ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${LIBDIR}/debug; \
-	fi
-	if [ ! -d ${DESTDIR}${MANDIR}3 ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${MANDIR}3; \
-	fi
-	if [ ! -d ${DESTDIR}${MANDIR}5 ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${MANDIR}5; \
-	fi
-	if [ ! -d ${DESTDIR}${PREFIX}/share/doc/png ]; then \
-	  ${INSTALL} -d -o root -g wheel ${DESTDIR}${PREFIX}/share/doc/png; \
-	fi
-
-afterinstall:
-	@rm -f ${DESTDIR}${LIBDIR}/libpng_pic.a
-	@rm -f ${DESTDIR}${LIBDIR}/debug/libpng.a
-	@rm -f ${DESTDIR}${PREFIX}/include/png.h
-	@rm -f ${DESTDIR}${PREFIX}/include/pngconf.h
-	@rm -f ${DESTDIR}${PREFIX}/include/pnglibconf.h
-	@rmdir ${DESTDIR}${LIBDIR}/debug 2>/dev/null || true
-	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
-		-m ${NONBINMODE} ${HDRS} ${DESTDIR}${PREFIX}/include
-	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
-		-m ${NONBINMODE} ${HDRS} ${DESTDIR}${PREFIX}/include
-	${INSTALL} ${INSTALL_COPY} -o ${SHAREOWN} -g ${SHAREGRP} \
-		-m ${NONBINMODE} ${DOCS} ${DESTDIR}${PREFIX}/share/doc/png
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 .include <bsd.lib.mk>
diff --git a/scripts/makefile.acorn b/scripts/makefile.riscos
similarity index 70%
rename from scripts/makefile.acorn
rename to scripts/makefile.riscos
index 00b8fb5..7baa148 100644
--- a/scripts/makefile.acorn
+++ b/scripts/makefile.riscos
@@ -1,14 +1,12 @@
 # Project:   libpng
 
+# Copyright (C) 2020 Cameron Cawley
+# Copyright (C) 1997 Tom Tanner
 
 # Toolflags:
-CCflags = -c -depend !Depend -IC:,Zlib: -g -throwback  -DRISCOS  -fnah
-C++flags = -c -depend !Depend -IC: -throwback
-Linkflags = -aif -c++ -o $@
-ObjAsmflags = -throwback -NoCache -depend !Depend
-CMHGflags =
+CCflags = -c -depend !Depend -IC:,C:zlib -g -throwback  -DRISCOS  -fnah -wz
+Linkflags = -aif -o $@
 LibFileflags = -c -l -o $@
-Squeezeflags = -o $@
 
 # Final targets:
 @.libpng-lib:   @.o.png @.o.pngerror @.o.pngrio @.o.pngwio @.o.pngmem \
@@ -27,14 +25,13 @@
 
 
 # User-editable dependencies:
-# (C) Copyright 1997 Tom Tanner
 Test: @.pngtest
-	<Prefix$Dir>.pngtest
-	@remove <Prefix$Dir>.pngtest
+	Run @.pngtest
+	@Remove @.pngtest
 
 #It would be nice if you could stop "make" listing from here on!
-@.pngtest:   @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib
-	Link $(Linkflags) @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib
+@.pngtest:   @.o.pngtest @.libpng-lib C:o.Stubs C:zlib.o.zlib
+	Link $(Linkflags) @.o.pngtest @.libpng-lib C:o.Stubs C:zlib.o.zlib
 
 .SUFFIXES: .o .mm .c
 
@@ -43,15 +40,15 @@
 .c.o:
 	cc $(ccflags) -o $@ $<
 
-# See scripts.mak.libpngconf for how to generate this:
-@.h.libpngconf: @.scripts.h.libpngconf
-	copy @.scripts.h.libpngconf $@
+# See scripts.pnglibconf/mak for how to generate this:
+@.h.pnglibconf: @.scripts.pnglibconf/h/prebuilt
+	Copy @.scripts.pnglibconf/h/prebuilt $@ ~CF~V
 
 # Static dependencies:
 @.o.png @.o.pngerror @.o.pngrio @.o.pngwio @.o.pngmem \
 @.o.pngpread @.o.pngset @.o.pngget @.o.pngread @.o.pngrtran \
 @.o.pngrutil @.o.pngtrans @.o.pngwrite @.o.pngwtran @.o.pngwutil \
-@.o.pngtest: @.h.libpngconf
+@.o.pngtest: @.h.pnglibconf
 
 
 # Dynamic dependencies:
diff --git a/scripts/makefile.sco b/scripts/makefile.sco
index 01d7eaa..8a8e50f 100644
--- a/scripts/makefile.sco
+++ b/scripts/makefile.sco
@@ -1,6 +1,7 @@
 # makefile for SCO OSr5  ELF and Unixware 7 with Native cc
 # Contributed by Mike Hopkirk (hops at sco.com) modified from Makefile.lnx
 #   force ELF build dynamic linking, SONAME setting in lib and RPATH in app
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998 Greg Roelofs
 # Copyright (C) 1996, 1997 Andreas Dilger
@@ -10,28 +11,21 @@
 # and license in png.h
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
 CC=cc
-AR_RC=ar rc
-MKDIR_P=mkdir
-LN_SF=ln -f -s
+AR=ar
 RANLIB=echo
+LN_SF=ln -f -s
 CP=cp
 RM_F=/bin/rm -f
 
-# where make install puts libpng.a, $(OLDSO)*, and png.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib
 #ZLIBINC=/usr/local/include
@@ -39,36 +33,17 @@
 ZLIBINC=../zlib
 
 CPPFLAGS=-I$(ZLIBINC)
-CFLAGS= -dy -belf -O3
+CFLAGS=-dy -belf -O3
+ARFLAGS=rc
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz -lm
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -80,32 +55,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -KPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"-belf\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -119,108 +77,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	-@$(RM_F) $(DI)/png.h
-	-@$(RM_F) $(DI)/pngconf.h
-	-@$(RM_F) $(DI)/pnglibconf.h
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	$(CC) $(CPPFLAGS) $(CFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* pngtest-static pngtesti \
-	pnglibconf.h libpng.pc
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pngtest-static pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sggcc b/scripts/makefile.sggcc
index 82efe7a..f694f6e 100644
--- a/scripts/makefile.sggcc
+++ b/scripts/makefile.sggcc
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so, SGI IRIX with 'cc'
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2001-2002, 2006, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -8,29 +9,20 @@
 
 # Library name:
 LIBNAME=libpng16
-PNGMAJ = 16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=echo
+LN_SF=ln -sf
 CP=cp
 RM_F=/bin/rm -f
 
-# Where make install puts libpng.a, libpng16.so, and libpng16/png.h
-# Prefix must be a full pathname.
-
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib32
 #ZLIBINC=/usr/local/include
@@ -46,74 +38,34 @@
 WARNMORE=
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS=$(ABI) -O $(WARNMORE) -fPIC -mabi=n32 # -g
-LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+ARFLAGS=rc
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm # -g
 LDSHARED=cc $(ABI) -shared -soname $(LIBSOMAJ) \
 	-set_version sgi$(PNGMAJ).0
 # See "man dso" for info about shared objects
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-#LIBPATH=$(exec_prefix)/lib32
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-all: libpng.a pngtest shared libpng.pc libpng-config
+all: libpng.a pngtest shared
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 shared: $(LIBSOMAJ)
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"$(ABI)\"; \
-	echo cppflags=\"\"; \
-	echo ldopts=\"$(ABI)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libdir=\"$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -129,108 +81,38 @@
 	echo Testing local static library.
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -rpath $(ZLIBLIB):$(DL) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -rpath $(ZLIBLIB):`$(BINPATH)/$(LIBNAME)-config --libdir` \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) libpng.a pngtest pngtesti pngout.png libpng.pc \
-	so_locations libpng-config $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) libpng.a pngtest pngout.png
+	$(RM_F) so_locations $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sgi b/scripts/makefile.sgi
index 5d9c23f..a60650c 100644
--- a/scripts/makefile.sgi
+++ b/scripts/makefile.sgi
@@ -1,4 +1,5 @@
 # makefile for libpng.a and libpng16.so, SGI IRIX with 'cc'
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2001-2002, 2006, 2007, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -8,29 +9,20 @@
 
 # Library name:
 LIBNAME=libpng16
-PNGMAJ = 16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=cc
-MKDIR_P=mkdir -p
-LN_SF=ln -sf
+AR=ar
 RANLIB=echo
+LN_SF=ln -sf
 CP=cp
 RM_F=/bin/rm -f
 
-# Where make install puts libpng.a, libpng16.so, and libpng16/png.h
-# Prefix must be a full pathname.
-
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib32
 #ZLIBINC=/usr/local/include
@@ -47,73 +39,34 @@
 # Note: -KPIC is the default anyhow
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
 #CFLAGS= $(ABI) -O $(WARNMORE) -KPIC # -g
-CFLAGS=$(ABI) -O $(WARNMORE)
-LDFLAGS_A=$(ABI) -L. -L$(ZLIBLIB) -lpng16 -lz -lm
-LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
+CFLAGS=$(ABI) -O $(WARNMORE) # -g
+ARFLAGS=rc
+LDFLAGS_A=$(ABI) -L. -L$(ZLIBLIB) -lpng16 -lz -lm # -g
+LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm # -g
 LDSHARED=cc $(ABI) -shared -soname $(LIBSOMAJ) \
 	-set_version sgi$(PNGMAJ).0
 # See "man dso" for info about shared objects
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-#LIBPATH=$(exec_prefix)/lib32
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS =  png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
 
-all: libpng.a pngtest shared libpng.pc libpng-config
+all: libpng.a pngtest shared
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo ccopts=\"$(ABI)\"; \
-	echo ldopts=\"$(ABI)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo libdir=\"$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -129,109 +82,38 @@
 	echo Testing local static library.
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(DL) -L$(ZLIBLIB) \
-	   -rpath $(ZLIBLIB):$(DL) \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -L$(ZLIBLIB) \
-	   -rpath $(ZLIBLIB):`$(BINPATH)/$(LIBNAME)-config --libdir` \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags`
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png libpng.pc libpng-config \
-	$(LIBSO) $(LIBSOMAJ)* \
-	so_locations pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* so_locations pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.so9 b/scripts/makefile.so9
index 93166f3..5af3ad9 100644
--- a/scripts/makefile.so9
+++ b/scripts/makefile.so9
@@ -1,6 +1,7 @@
 # makefile for libpng on Solaris 9 (beta) with Forte cc
 # Updated by Chad Schrock for Solaris 9
 # Contributed by William L. Sebok, based on makefile.linux
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2008, 2010-2014 Glenn Randers-Pehrson
 # Copyright (C) 1998-2001 Greg Roelofs
 # Copyright (C) 1996-1997 Andreas Dilger
@@ -10,29 +11,22 @@
 # and license in png.h
 
 # Library name:
-PNGMAJ = 16
-LIBNAME = libpng16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
 # gcc 2.95 doesn't work.
 CC=cc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -f -s
+AR=ar
 RANLIB=echo
+LN_SF=ln -f -s
 CP=cp
 RM_F=/bin/rm -f
 
-# Where make install puts libpng.a, $(OLDSO)*, and png.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 # Changing these to ../zlib poses a security risk.  If you want
 # to have zlib in an adjacent directory, specify the full path instead of "..".
@@ -44,41 +38,18 @@
 ZLIBLIB=/usr/lib
 ZLIBINC=/usr/include
 
-#WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-#CFLAGS=-W -Wall -O3 $(WARNMORE) -g
 CFLAGS=-O3
+ARFLAGS=rc
 LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
 
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
-
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -90,32 +61,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -KPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-R$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -141,107 +95,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   -L$(DL) -L$(ZLIBLIB)  -R$(ZLIBLIB) -R$(DL)
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.solaris b/scripts/makefile.solaris
index f6d7b58..c4d7709 100644
--- a/scripts/makefile.solaris
+++ b/scripts/makefile.solaris
@@ -1,4 +1,5 @@
 # makefile for libpng on Solaris 2.x with gcc
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2004, 2006-2008, 2010-2014 Glenn Randers-Pehrson
 # Contributed by William L. Sebok, based on makefile.linux
 # Copyright (C) 1998 Greg Roelofs
@@ -9,28 +10,21 @@
 # and license in png.h
 
 # Library name:
-LIBNAME = libpng16
-PNGMAJ = 16
+LIBNAME=libpng16
+PNGMAJ=16
 
 # Shared library names:
 LIBSO=$(LIBNAME).so
 LIBSOMAJ=$(LIBNAME).so.$(PNGMAJ)
-LIBSOREL=$(LIBSOMAJ).$(RELEASE)
-OLDSO=libpng.so
 
 # Utilities:
-AR_RC=ar rc
 CC=gcc
-MKDIR_P=mkdir -p
-LN_SF=ln -f -s
+AR=ar
 RANLIB=echo
+LN_SF=ln -f -s
 CP=cp
 RM_F=/bin/rm -f
 
-# Where make install puts libpng.a, libpng16.so*, and png.h
-prefix=/usr/local
-exec_prefix=$(prefix)
-
 # Where the zlib library and include files are located
 # Changing these to ../zlib poses a security risk.  If you want
 # to have zlib in an adjacent directory, specify the full path instead of "..".
@@ -42,38 +36,19 @@
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
 	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wstrict-prototypes -Wmissing-prototypes # -Wconversion
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-W -Wall -O # $(WARNMORE) -g
-LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm
-
-INCPATH=$(prefix)/include
-LIBPATH=$(exec_prefix)/lib
-MANPATH=$(prefix)/man
-BINPATH=$(exec_prefix)/bin
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
-DB=$(DESTDIR)$(BINPATH)
-DI=$(DESTDIR)$(INCPATH)
-DL=$(DESTDIR)$(LIBPATH)
-DM=$(DESTDIR)$(MANPATH)
+CFLAGS=-O -Wall -Wextra -Wundef # $(WARNMORE) -g
+ARFLAGS=rc
+LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng16 -lz -lm # -g
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -85,33 +60,15 @@
 .c.pic.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -fPIC -o $@ $*.c
 
-all: libpng.a $(LIBSO) pngtest libpng.pc libpng-config
+all: libpng.a $(LIBSO) pngtest
 
 pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
-libpng.pc:
-	cat scripts/libpng.pc.in | sed -e s!@prefix@!$(prefix)! \
-	-e s!@exec_prefix@!$(exec_prefix)! \
-	-e s!@libdir@!$(LIBPATH)! \
-	-e s!@includedir@!$(INCPATH)! \
-	-e s!-lpng16!-lpng16\ -lz\ -lm! > libpng.pc
-
-libpng-config:
-	( cat scripts/libpng-config-head.in; \
-	echo prefix=\"$(prefix)\"; \
-	echo I_opts=\"-I$(INCPATH)/$(LIBNAME)\"; \
-	echo cppflags=\"\"; \
-	echo L_opts=\"-L$(LIBPATH)\"; \
-	echo R_opts=\"-R$(LIBPATH)\"; \
-	echo libs=\"-lpng16 -lz -lm\"; \
-	cat scripts/libpng-config-body.in ) > libpng-config
-	chmod +x libpng-config
-
 $(LIBSO): $(LIBSOMAJ)
 	$(LN_SF) $(LIBSOMAJ) $(LIBSO)
 
@@ -137,107 +94,38 @@
 test: pngtest
 	./pngtest
 
-install-headers: png.h pngconf.h pnglibconf.h
-	-@if [ ! -d $(DI) ]; then $(MKDIR_P) $(DI); fi
-	-@if [ ! -d $(DI)/$(LIBNAME) ]; then $(MKDIR_P) $(DI)/$(LIBNAME); fi
-	cp png.h pngconf.h pnglibconf.h $(DI)/$(LIBNAME)
-	chmod 644 $(DI)/$(LIBNAME)/png.h $(DI)/$(LIBNAME)/pngconf.h $(DI)/$(LIBNAME)/pnglibconf.h
-	-@$(RM_F) $(DI)/png.h $(DI)/pngconf.h $(DI)/pnglibconf.h
-	-@$(RM_F) $(DI)/libpng
-	(cd $(DI); $(LN_SF) $(LIBNAME) libpng; $(LN_SF) $(LIBNAME)/* .)
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-static: install-headers libpng.a
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	cp libpng.a $(DL)/$(LIBNAME).a
-	chmod 644 $(DL)/$(LIBNAME).a
-	-@$(RM_F) $(DL)/libpng.a
-	(cd $(DL); $(LN_SF) $(LIBNAME).a libpng.a)
+install-static:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
-install-shared: install-headers $(LIBSOMAJ) libpng.pc
-	-@if [ ! -d $(DL) ]; then $(MKDIR_P) $(DL); fi
-	-@$(RM_F) $(DL)/$(LIBSO)
-	-@$(RM_F) $(DL)/$(LIBSOREL)
-	-@$(RM_F) $(DL)/$(OLDSO)
-	cp $(LIBSOMAJ) $(DL)/$(LIBSOREL)
-	chmod 755 $(DL)/$(LIBSOREL)
-	(cd $(DL); \
-	$(LN_SF) $(LIBSOREL) $(LIBSO); \
-	$(LN_SF) $(LIBSO) $(OLDSO))
-	-@if [ ! -d $(DL)/pkgconfig ]; then $(MKDIR_P) $(DL)/pkgconfig; fi
-	-@$(RM_F) $(DL)/pkgconfig/$(LIBNAME).pc
-	-@$(RM_F) $(DL)/pkgconfig/libpng.pc
-	cp libpng.pc $(DL)/pkgconfig/$(LIBNAME).pc
-	chmod 644 $(DL)/pkgconfig/$(LIBNAME).pc
-	(cd $(DL)/pkgconfig; $(LN_SF) $(LIBNAME).pc libpng.pc)
-
-install-man: libpng.3 libpngpf.3 png.5
-	-@if [ ! -d $(DM) ]; then $(MKDIR_P) $(DM); fi
-	-@if [ ! -d $(DM)/man3 ]; then $(MKDIR_P) $(DM)/man3; fi
-	-@$(RM_F) $(DM)/man3/libpng.3
-	-@$(RM_F) $(DM)/man3/libpngpf.3
-	cp libpng.3 $(DM)/man3
-	cp libpngpf.3 $(DM)/man3
-	-@if [ ! -d $(DM)/man5 ]; then $(MKDIR_P) $(DM)/man5; fi
-	-@$(RM_F) $(DM)/man5/png.5
-	cp png.5 $(DM)/man5
-
-install-config: libpng-config
-	-@if [ ! -d $(DB) ]; then $(MKDIR_P) $(DB); fi
-	-@$(RM_F) $(DB)/libpng-config
-	-@$(RM_F) $(DB)/$(LIBNAME)-config
-	cp libpng-config $(DB)/$(LIBNAME)-config
-	chmod 755 $(DB)/$(LIBNAME)-config
-	(cd $(DB); $(LN_SF) $(LIBNAME)-config libpng-config)
-
-install: install-static install-shared install-man install-config
-
-# If you installed in $(DESTDIR), test-installed won't work until you
-# move the library to its final location.  Use test-dd to test it
-# before then.
-
-test-dd:
-	echo
-	echo Testing installed dynamic shared library in $(DL).
-	$(CC) -I$(DI) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtestd `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   -L$(DL) -L$(ZLIBLIB) -R$(ZLIBLIB) -R$(DL)
-	./pngtestd pngtest.png
-
-test-installed:
-	echo
-	echo Testing installed dynamic shared library.
-	$(CC) $(CPPFLAGS) \
-	   `$(BINPATH)/$(LIBNAME)-config --cflags` pngtest.c \
-	   -o pngtesti `$(BINPATH)/$(LIBNAME)-config --ldflags` \
-	   -L$(ZLIBLIB) -R$(ZLIBLIB)
-	./pngtesti pngtest.png
+install-shared:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngtesti pngout.png \
-	libpng-config $(LIBSO) $(LIBSOMAJ)* \
-	libpng.pc pnglibconf.h
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png
+	$(RM_F) $(LIBSO) $(LIBSOMAJ)* pnglibconf.h
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o png.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o      png.pic.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o pngerror.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o pngrio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o pngwio.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o pngmem.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o pngset.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o pngget.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o pngread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o   pngget.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o   pngmem.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o  pngread.pic.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o   pngrio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o pngrtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o pngrutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o   pngset.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o pngtrans.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o   pngwio.pic.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o pngwrite.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o pngwtran.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o pngwutil.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o pngpread.pic.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
 pngtest.o: png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.std b/scripts/makefile.std
index 2f4871d..6d69bf5 100644
--- a/scripts/makefile.std
+++ b/scripts/makefile.std
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -6,21 +7,6 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib
 #ZLIBINC=/usr/local/include
@@ -28,30 +14,31 @@
 ZLIBINC=../zlib
 
 CC = cc
-AR_RC = ar rc
-MKDIR_P = mkdir
-LN_SF = ln -sf
+CPP = $(CC) -E
+LD = $(CC)
+AR = ar
 RANLIB = ranlib
-CP = cp
+MV_F = mv -f
 RM_F = rm -f
 AWK = awk
-SED = sed
-CPP = $(CC) -E
-ECHO = echo
 
+NOHWOPT = -DPNG_ARM_NEON_OPT=0 -DPNG_MIPS_MSA_OPT=0 \
+	-DPNG_POWERPC_VSX_OPT=0 -DPNG_INTEL_SSE_OPT=0
 DFNFLAGS = # DFNFLAGS contains -D options to use in the libpng build
 DFA_EXTRA = # extra files that can be used to control configuration
-CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
+CPPFLAGS = -I$(ZLIBINC) $(NOHWOPT) # -DPNG_DEBUG=5
 CFLAGS = -O # -g
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng -lz -lm
+ARFLAGS = rc
+LDFLAGS = -L$(ZLIBLIB) # -g
+LIBS = -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -62,73 +49,56 @@
 # copy this if the following doesn't work.
 pnglibconf.h: pnglibconf.dfn
 	$(RM_F) $@ pnglibconf.c pnglibconf.out pnglibconf.tmp
-	$(ECHO) '#include "pnglibconf.dfn"' >pnglibconf.c
-	$(ECHO) "If '$(CC) -E' crashes try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
+	echo '#include "pnglibconf.dfn"' >pnglibconf.c
+	@echo "## If '$(CC) -E' fails, try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
 	$(CPP) $(DFNFLAGS) pnglibconf.c >pnglibconf.out
-	$(AWK) -f "scripts/dfn.awk" out="pnglibconf.tmp" pnglibconf.out 1>&2
-	mv pnglibconf.tmp $@
+	$(AWK) -f scripts/dfn.awk out=pnglibconf.tmp pnglibconf.out >&2
+	$(MV_F) pnglibconf.tmp $@
 
 pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
 	$(RM_F) $@ pnglibconf.pre pnglibconf.tmp
-	$(ECHO) "Calling $(AWK) from scripts/pnglibconf.mak" >&2
-	$(ECHO) "If 'awk' crashes try a better awk (e.g. AWK='nawk')" >&2
-	$(AWK) -f scripts/options.awk out="pnglibconf.pre"\
+	@echo "## Calling $(AWK) from scripts/pnglibconf.mak" >&2
+	@echo "## If 'awk' fails, try a better awk (e.g. AWK='nawk')" >&2
+	$(AWK) -f scripts/options.awk out=pnglibconf.pre\
 	    version=search pngconf.h scripts/pnglibconf.dfa\
-	    pngusr.dfa $(DFA_XTRA) 1>&2
-	$(AWK) -f scripts/options.awk out="pnglibconf.tmp" pnglibconf.pre 1>&2
-	mv pnglibconf.tmp $@
+	    pngusr.dfa $(DFA_XTRA) >&2
+	$(AWK) -f scripts/options.awk out=pnglibconf.tmp pnglibconf.pre >&2
+	$(MV_F) pnglibconf.tmp $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 test: pngtest
 	./pngtest
 
-install: libpng.a pnglibconf.h
-	-@$(MKDIR_P) $(DESTDIR)$(INCPATH)
-	-@$(MKDIR_P) $(DESTDIR)$(INCPATH)/libpng
-	-@$(MKDIR_P) $(DESTDIR)$(LIBPATH)
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/png.h
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/pngconf.h
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/pnglibconf.h
-	cp png.h $(DESTDIR)$(INCPATH)/libpng
-	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
-	cp pnglibconf.h $(DESTDIR)$(INCPATH)/libpng
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pnglibconf.h
-	(cd $(DESTDIR)$(INCPATH); ln -f -s libpng/* .)
-	cp libpng.a $(DESTDIR)$(LIBPATH)
-	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h pnglibconf.c \
-	pnglibconf.out
-
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
+	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
+	$(RM_F) pnglibconf.c pnglibconf.dfn pnglibconf.out pnglibconf.pre
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.sunos b/scripts/makefile.sunos
index 9a0e28e..e8c046b 100644
--- a/scripts/makefile.sunos
+++ b/scripts/makefile.sunos
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020-2024 Cosmin Truta
 # Copyright (C) 2002, 2006, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -6,51 +7,30 @@
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-INCPATH=$(prefix)/include
-LIBPATH=$(prefix)/lib
-
-# override DESTDIR= on the make install command line to easily support
-# installing into a temporary location.  Example:
-#
-#    make install DESTDIR=/tmp/build/libpng
-#
-# If you're going to install into a temporary location
-# via DESTDIR, $(DESTDIR)$(prefix) must already exist before
-# you execute make install.
-DESTDIR=
-
 # Where the zlib library and include files are located
 #ZLIBLIB=/usr/local/lib
 #ZLIBINC=/usr/local/include
 ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
-
-WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow -Wconversion \
-	-Wmissing-declarations -Wtraditional -Wcast-align \
-	-Wstrict-prototypes -Wmissing-prototypes
-
 CC=gcc
-AR_RC=ar rc
-MKDIR_P=mkdir -p
-LN_SF=ln -f -s
+AR=ar
 RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
 
 CPPFLAGS=-I$(ZLIBINC) # -DPNG_DEBUG=5
-CFLAGS=-O # $(WARNMORE)
+CFLAGS=-O
+ARFLAGS=rc
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -61,7 +41,7 @@
 	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
@@ -70,46 +50,29 @@
 test: pngtest
 	./pngtest
 
-install: libpng.a
-	-@$(MKDIR_P) $(DESTDIR)$(INCPATH)
-	-@$(MKDIR_P) $(DESTDIR)$(INCPATH)/libpng
-	-@$(MKDIR_P) $(DESTDIR)$(LIBPATH)
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/png.h
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/pngconf.h
-	-@$(RM_F) $(DESTDIR)$(INCPATH)/pnglibconf.h
-	cp png.h $(DESTDIR)$(INCPATH)/libpng
-	cp pngconf.h $(DESTDIR)$(INCPATH)/libpng
-	cp pnglibconf.h $(DESTDIR)$(INCPATH)/libpng
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/png.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pngconf.h
-	chmod 644 $(DESTDIR)$(INCPATH)/libpng/pnglibconf.h
-	(cd $(DESTDIR)$(INCPATH); $(LN_SF) libpng/* .)
-	cp libpng.a $(DESTDIR)$(LIBPATH)
-	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
+install:
+	@echo "The $@ target is no longer supported by this makefile."
+	@false
 
 clean:
 	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
 
-DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
-writelock:
-	chmod a-w *.[ch35] $(DOCS) scripts/*
-
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h
diff --git a/scripts/makefile.vcwin-arm64 b/scripts/makefile.vcwin-arm64
new file mode 100644
index 0000000..1e98d16
--- /dev/null
+++ b/scripts/makefile.vcwin-arm64
@@ -0,0 +1,123 @@
+# makefile for libpng on win-arm64
+# Copyright (C) 2021 Gabor Kertesz
+# Copyright (C) 1998 Tim Wegner
+# Copyright (C) 2006,2009,2011,2014 Glenn Randers-Pehrson
+#
+# This code is released under the libpng license.
+# For conditions of distribution and use, see the disclaimer
+# and license in png.h
+#
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+# To use, do "nmake /f scripts\makefile.vcwin-arm64"
+
+# -------- Microsoft Visual C++ 2.0 and later --------
+
+# Compiler, linker, librarian and other tools
+CC = cl
+LD = link
+AR = lib
+CPPFLAGS = -I..\zlib
+CFLAGS  = -nologo -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -DPNG_ARM_NEON_OPT=1 -MD -O2 -W3
+LDFLAGS = -nologo
+ARFLAGS = -nologo
+CP = copy
+RM = del
+
+# Uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
+# Pre-built configuration
+# See scripts\pnglibconf.mak for more options
+PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
+
+# File extensions
+O = .obj
+
+# File lists
+OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
+OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
+OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
+OBJS4 = arm_init$(O) filter_neon_intrinsics$(O) palette_neon_intrinsics$(O)
+OBJS  = $(OBJS1) $(OBJS2) $(OBJS3) $(OBJS4)
+
+# Targets
+all: libpng.lib
+
+pnglibconf.h: $(PNGLIBCONF_H_PREBUILT)
+	$(CP) $(PNGLIBCONF_H_PREBUILT) $@
+
+png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+arm_init$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+filter_neon_intrinsics$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+palette_neon_intrinsics$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) arm\$*.c $(ERRFILE)
+
+libpng.lib: $(OBJS)
+	-$(RM) $@
+	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
+
+pngtest.exe: pngtest$(O) libpng.lib
+	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h pnglibconf.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+test: pngtest.exe
+	pngtest.exe
+
+clean:
+	-$(RM) *$(O)
+	-$(RM) libpng.lib
+	-$(RM) pnglibconf.h
+	-$(RM) pngtest.exe
+	-$(RM) pngout.png
+
+# End of makefile for libpng
diff --git a/scripts/makefile.vcwin32 b/scripts/makefile.vcwin32
index 2bd143c..7620322 100644
--- a/scripts/makefile.vcwin32
+++ b/scripts/makefile.vcwin32
@@ -22,17 +22,17 @@
 CP = copy
 RM = del
 
+# Uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs.log
+
 # Pre-built configuration
 # See scripts\pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
 
 # File extensions
-O=.obj
+O = .obj
 
-#uncomment next to put error messages in a file
-#ERRFILE= >> pngerrs.log
-
-# Variables
+# File lists
 OBJS1 = png$(O) pngerror$(O) pngget$(O) pngmem$(O) pngpread$(O)
 OBJS2 = pngread$(O) pngrio$(O) pngrtran$(O) pngrutil$(O) pngset$(O)
 OBJS3 = pngtrans$(O) pngwio$(O) pngwrite$(O) pngwtran$(O) pngwutil$(O)
@@ -47,39 +47,39 @@
 png$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngget$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngpread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
+pngread$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 pngrtran$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngrutil$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
-pngerror$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngmem$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngrio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
-pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
 pngtrans$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
+pngwio$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 pngwrite$(O): png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
 
@@ -93,14 +93,14 @@
 	-$(RM) $@
 	$(AR) $(ARFLAGS) -out:$@ $(OBJS) $(ERRFILE)
 
-pngtest$(O): png.h pngconf.h pnglibconf.h
-	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
-
 pngtest.exe: pngtest$(O) libpng.lib
 	$(LD) $(LDFLAGS) -out:$@ pngtest$(O) libpng.lib ..\zlib\zlib.lib $(ERRFILE)
 
+pngtest$(O): png.h pngconf.h pnglibconf.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $*.c $(ERRFILE)
+
 test: pngtest.exe
-	pngtest
+	pngtest.exe
 
 clean:
 	-$(RM) *$(O)
@@ -110,4 +110,3 @@
 	-$(RM) pngout.png
 
 # End of makefile for libpng
-
diff --git a/scripts/options.awk b/scripts/options.awk
index fef5dfd..b74223a 100755
--- a/scripts/options.awk
+++ b/scripts/options.awk
@@ -1,8 +1,7 @@
 #!/bin/awk -f
+
 # scripts/options.awk - library build configuration control
 #
-# last changed in libpng version 1.6.11 - June 5, 2014
-#
 # Copyright (c) 1998-2014 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
@@ -243,7 +242,7 @@
 
 # option NAME ( (requires|enables|if) NAME* | on | off | disabled |
 #                sets SETTING VALUE+ )*
-#     
+#
 #   Declares an option 'NAME' and describes its default setting (disabled)
 #   and its relationship to other options.  The option is disabled
 #   unless *all* the options listed after 'requires' are set and at
@@ -402,8 +401,10 @@
 
    if (i > NF) {
       # Output new 'option' lines to the intermediate file (out)
-      print "option READ_" opt, "requires READ_ANCILLARY_CHUNKS" reqread, "enables", opt enables , onoff >out
-      print "option WRITE_" opt, "requires WRITE_ANCILLARY_CHUNKS" reqwrite, "enables", opt enables, onoff >out
+      print "option READ_" opt, "requires READ_ANCILLARY_CHUNKS" reqread,
+            "enables", opt enables , onoff >out
+      print "option WRITE_" opt, "requires WRITE_ANCILLARY_CHUNKS" reqwrite,
+            "enables", opt enables, onoff >out
       next
    }
    # Else hit the error handler below - bad line format!
@@ -732,7 +733,9 @@
          # 'have_ifs' here means that everything = "off" still allows an 'if' on
          # an otherwise enabled option to turn it on; otherwise the 'if'
          # handling is effectively disabled by 'everything = off'
-         if (option[i] == "off" || option[i] == "disabled" && everything != "on" || option[i] == "enabled" && everything == "off" && !have_ifs) {
+         if ((option[i] == "off") ||
+             (option[i] == "disabled" && everything != "on") ||
+             (option[i] == "enabled" && everything == "off" && !have_ifs)) {
             print "#      undef PNG_on /*default off*/" >out
          } else {
             print "#      ifdef PNG_NO_" i >out
@@ -753,7 +756,8 @@
          # pnglibconf.h
          print "#   ifdef PNG_on" >out
          if (i ~ /^fail_/) {
-            print error, i, "is on: enabled by:" iffs[i] enabledby[i] ", requires" requires[i] end >out
+            print error, i, "is on:",
+                  "enabled by:" iffs[i] enabledby[i] ", requires" requires[i] end >out
          } else if (i !~ /^ok_/) {
             print def i sup >out
             # Supported option, set required settings
@@ -780,7 +784,8 @@
                print und i une >out
             }
             if (i ~ /^ok_/) {
-               print error, i, "not enabled: requires:" requires[i] ", enabled by:" iffs[i] enabledby[i] end >out
+               print error, i, "not enabled: ",
+                     "requires:" requires[i] ", enabled by:" iffs[i] enabledby[i] end >out
             }
             print "#endif" >out
          }
diff --git a/scripts/pnglibconf.dfa b/scripts/pnglibconf.dfa
index 4dcaf7c..739805d 100644
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -8,7 +8,7 @@
 com
 version
 com
-com Copyright (c) 2018-2019 Cosmin Truta
+com Copyright (c) 2018-2024 Cosmin Truta
 com Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
 com
 com This code is released under the libpng license.
@@ -69,9 +69,9 @@
 #
 # 1) Create 'pngusr.h', enter the required private build information
 # detailed below and #define PNG_NO_<option> for each option you
-# don't want in that file in that file.  You can also turn on options
-# using PNG_<option>_SUPPORTED.  When you have finished rerun
-# configure and rebuild pnglibconf.h file with -DPNG_USER_CONFIG:
+# don't want in that file.  You can also turn on options using
+# PNG_<option>_SUPPORTED.  When you have finished, rerun configure
+# and rebuild pnglibconf.h file with -DPNG_USER_CONFIG:
 #
 #  make clean
 #  CPPFLAGS='-DPNG_USER_CONFIG' ./configure
@@ -256,6 +256,55 @@
 option POWERPC_VSX_CHECK disabled,
   sets POWERPC_VSX_OPT 1
 
+# These options are specific to the MIPS MSA hardware optimizations.
+#
+# MIPS_MSA_OPT: unset: check at compile time (__mips_msa must be defined by
+#                      the compiler, typically as a result of specifying
+#                      "-mmsa -mfp64" compiler flags)
+#                   0: disable (even if the CPU supports MSA.)
+#                   1: check at run time (via MIPS_MSA_{API,CHECK})
+#                   2: switch on unconditionally (inadvisable - instead pass
+#                      -mmsa -mfp64 to compiler options)
+#           When building libpng avoid using any setting other than '0'; '1' is
+#           set automatically when either 'API' or 'CHECK' are configured in,
+#           '2' should not be necessary as "-mmsa -mfp64" will achieve the same
+#           effect as well as applying MSA optimizations to the rest of the
+#           libpng code.
+#           NOTE: any setting other than '0' requires ALIGNED_MEMORY
+# MIPS_MSA_API:   (PNG_MIPS_MSA == 1) allow the optimization to be switched on
+#                 with png_set_option.
+# MIPS_MSA_CHECK: (PNG_MIPS_MSA == 1) compile a run-time check to see if MSA
+#                 extensions are supported.
+setting MIPS_MSA_OPT
+option MIPS_MSA_API disabled requires ALIGNED_MEMORY enables SET_OPTION,
+  sets MIPS_MSA_OPT 1
+option MIPS_MSA_CHECK disabled requires ALIGNED_MEMORY,
+  sets MIPS_MSA_OPT 1
+
+# These options are specific to the MIPS MMI hardware optimizations.
+#
+# MIPS_MMI_OPT: unset: check at compile time (__mips_loongson_mmi must be defined by
+#                      the compiler, typically as a result of specifying
+#                      "-mloongson-mmi -march=loongson3a" compiler flags)
+#                   0: disable (even if the CPU supports MMI.)
+#                   1: check at run time (via MIPS_MMI_{API,CHECK})
+#                   2: switch on unconditionally (inadvisable - instead pass
+#                      -mloongson-mmi -march=loongson3a to compiler options)
+#           When building libpng avoid using any setting other than '0'; '1' is
+#           set automatically when either 'API' or 'CHECK' are configured in,
+#           '2' should not be necessary as "-mloongson-mmi -march=loongson3a" will achieve the same
+#           effect as well as applying MMI optimizations to the rest of the
+#           libpng code.
+# MIPS_MMI_API:   (PNG_MIPS_MMI == 1) allow the optimization to be switched on
+#                 with png_set_option
+# MIPS_MMI_CHECK: (PNG_MIPS_MMI == 1) compile a run-time check to see if MMI
+#                 extensions are supported.
+setting MIPS_MMI_OPT
+option MIPS_MMI_API disabled requires ALIGNED_MEMORY enables SET_OPTION,
+  sets MIPS_MMI_OPT 1
+option MIPS_MMI_CHECK disabled requires ALIGNED_MEMORY,
+  sets MIPS_MMI_OPT 1
+
 
 # These settings configure the default compression level (0-9) and 'strategy';
 # strategy is as defined by the implementors of zlib. It describes the input
@@ -336,6 +385,34 @@
 option BENIGN_WRITE_ERRORS requires BENIGN_ERRORS disabled
 option BENIGN_READ_ERRORS requires BENIGN_ERRORS
 
+# Adler32 checksum
+#
+# This option allows the check of the Adler32 checksum performed by zlib to
+# be turned off for IDAT chunks (only).  Unless this option is enabled and
+# turned on (not the default even if enabled) a failed Adler32 at the end of the
+# stream will result in a decompression (inflate) failure on read even though
+# the entire image might have been read successfully.
+#
+# This option relies on an undocumented function 'inflateValidate' which is
+# present in only some versions of zlib.  If the function is not present in the
+# zlib used with libpng code which uses -lpng is likely to fail to link or to
+# launch in the case of a DLL.
+#
+# Therefore this option is currently disabled by default; it has to be turned on
+# in pngusr.dfa and then the application program has to explicitly turn the
+# functionality on by calling png_set_option.
+#
+# Furthermore the option is explicitly turned off here if the zlib version
+# number is below that required - libpng wouldn't compile in that case if the
+# option were turned on.
+option DISABLE_ADLER32_CHECK requires READ enables SET_OPTION disabled
+
+# ZLIB_VERNUM must be used here, not PNG_ZLIB_VERNUM, because
+# scripts/options.awk ends up putting this test adhead of the setting of
+# PNG_ZLIB_VERNUM (apparently above, but not because of the two-pass processing)
+@#if ZLIB_VERNUM < 0x1290
+@#   define PNG_NO_DISABLE_ADLER32_CHECK
+@#endif
 
 # Generic options - affect both read and write.
 
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index 8859a06..9dd5408 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -1,8 +1,8 @@
 /* pnglibconf.h - library build configuration */
 
-/* libpng version 1.6.38.git */
+/* libpng version 1.6.43.git */
 
-/* Copyright (c) 2018-2019 Cosmin Truta */
+/* Copyright (c) 2018-2024 Cosmin Truta */
 /* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson */
 
 /* This code is released under the libpng license. */
@@ -27,6 +27,7 @@
 #define PNG_COLORSPACE_SUPPORTED
 #define PNG_CONSOLE_IO_SUPPORTED
 #define PNG_CONVERT_tIME_SUPPORTED
+/*#undef PNG_DISABLE_ADLER32_CHECK_SUPPORTED*/
 #define PNG_EASY_ACCESS_SUPPORTED
 /*#undef PNG_ERROR_NUMBERS_SUPPORTED*/
 #define PNG_ERROR_TEXT_SUPPORTED
@@ -41,6 +42,10 @@
 #define PNG_INCH_CONVERSIONS_SUPPORTED
 #define PNG_INFO_IMAGE_SUPPORTED
 #define PNG_IO_STATE_SUPPORTED
+/*#undef PNG_MIPS_MMI_API_SUPPORTED*/
+/*#undef PNG_MIPS_MMI_CHECK_SUPPORTED*/
+/*#undef PNG_MIPS_MSA_API_SUPPORTED*/
+/*#undef PNG_MIPS_MSA_CHECK_SUPPORTED*/
 #define PNG_MNG_FEATURES_SUPPORTED
 #define PNG_POINTER_INDEXING_SUPPORTED
 /*#undef PNG_POWERPC_VSX_API_SUPPORTED*/
diff --git a/scripts/pnglibconf.mak b/scripts/pnglibconf.mak
index c125ca2..34a240e 100755
--- a/scripts/pnglibconf.mak
+++ b/scripts/pnglibconf.mak
@@ -11,12 +11,12 @@
 AWK = mawk
 AWK = nawk
 AWK = one-true-awk
-AWK = awk  # Crashes on SunOS 5.10 - use 'nawk'
-CPP = $(CC) -E # On SUN OS 5.10 if this causes problems use /lib/cpp
+AWK = awk      # This fails on SunOS 5.10; use 'nawk'
+CPP = $(CC) -E # If this fails on SunOS 5.10, use '/lib/cpp'
 
-MOVE = mv
+MOVE = mv -f
 DELETE = rm -f
-ECHO = echo
+
 DFA_XTRA = # Put your configuration file here, see scripts/pnglibconf.dfa.  Eg:
 # DFA_XTRA = pngusr.dfa
 
@@ -25,27 +25,27 @@
 # as appropriate
 DFNFLAGS = $(DEFS) $(CPPFLAGS) $(CFLAGS)
 
-# srcdir is a defacto standard for the location of the source
+# srcdir is a de-facto standard for the location of the source
 srcdir = .
 
 # The standard pnglibconf.h exists as scripts/pnglibconf.h.prebuilt,
 # copy this if the following doesn't work.
 pnglibconf.h: pnglibconf.dfn
 	$(DELETE) $@ pnglibconf.c pnglibconf.out pnglibconf.tmp
-	$(ECHO) '#include "pnglibconf.dfn"' >pnglibconf.c
-	$(ECHO) "If '$(CC) -E' crashes try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
+	echo '#include "pnglibconf.dfn"' >pnglibconf.c
+	@echo "## If '$(CC) -E' fails, try /lib/cpp (e.g. CPP='/lib/cpp')" >&2
 	$(CPP) $(DFNFLAGS) pnglibconf.c >pnglibconf.out
-	$(AWK) -f "$(srcdir)/scripts/dfn.awk" out="pnglibconf.tmp" pnglibconf.out 1>&2
+	$(AWK) -f $(srcdir)/scripts/dfn.awk out=pnglibconf.tmp pnglibconf.out >&2
 	$(MOVE) pnglibconf.tmp $@
 
 pnglibconf.dfn: $(srcdir)/scripts/pnglibconf.dfa $(srcdir)/scripts/options.awk $(srcdir)/pngconf.h $(srcdir)/pngusr.dfa $(DFA_XTRA)
 	$(DELETE) $@ pnglibconf.pre pnglibconf.tmp
-	$(ECHO) "Calling $(AWK) from scripts/pnglibconf.mak" >&2
-	$(ECHO) "If 'awk' crashes try a better awk (e.g. AWK='nawk')" >&2
-	$(AWK) -f $(srcdir)/scripts/options.awk out="pnglibconf.pre"\
+	@echo "## Calling $(AWK) from scripts/pnglibconf.mak" >&2
+	@echo "## If 'awk' fails, try a better awk (e.g. AWK='nawk')" >&2
+	$(AWK) -f $(srcdir)/scripts/options.awk out=pnglibconf.pre\
 	    version=search $(srcdir)/pngconf.h $(srcdir)/scripts/pnglibconf.dfa\
-	    $(srcdir)/pngusr.dfa $(DFA_XTRA) 1>&2
-	$(AWK) -f $(srcdir)/scripts/options.awk out="pnglibconf.tmp" pnglibconf.pre 1>&2
+	    $(srcdir)/pngusr.dfa $(DFA_XTRA) >&2
+	$(AWK) -f $(srcdir)/scripts/options.awk out=pnglibconf.tmp pnglibconf.pre >&2
 	$(MOVE) pnglibconf.tmp $@
 
 clean-pnglibconf:
diff --git a/scripts/pngwin.rc b/scripts/pngwin.rc
index 9335cbb..87702a4 100644
--- a/scripts/pngwin.rc
+++ b/scripts/pngwin.rc
@@ -89,12 +89,12 @@
 #endif /* PNG_USER_VERSIONINFO_COMPANYNAME */
       VALUE "FileDescription", "PNG image compression library\000"
       VALUE "FileVersion", PNG_LIBPNG_VER_STRING "\000"
-      VALUE "InternalName", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_DLLNUM) PNG_LIBPNG_DLLFNAME_POSTFIX " (Windows 32 bit)\000"
-      VALUE "LegalCopyright", "\251 1998-2009 Glenn Randers-Pehrson et al.\000"
+      VALUE "InternalName", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_SHAREDLIB) PNG_LIBPNG_DLLFNAME_POSTFIX " (Windows)\000"
+      VALUE "LegalCopyright", "\251 1998-2024 PNG Reference Library Authors\000"
 #ifdef PNG_USER_VERSIONINFO_LEGALTRADEMARKS
       VALUE "LegalTrademarks", PNG_USER_VERSIONINFO_LEGALTRADEMARKS "\000"
 #endif /* PNG_USER_VERSIONINFO_LEGALTRADEMARKS */
-      VALUE "OriginalFilename", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_DLLNUM) PNG_LIBPNG_DLLFNAME_POSTFIX ".DLL\000"
+      VALUE "OriginalFilename", PNG_LIBPNG_DLLFNAME QUOTE(PNG_LIBPNG_VER_SHAREDLIB) PNG_LIBPNG_DLLFNAME_POSTFIX ".DLL\000"
 #ifdef PNG_USER_PRIVATEBUILD
       VALUE "PrivateBuild", PNG_USER_PRIVATEBUILD "\000"
 #endif /* PNG_USER_PRIVATEBUILD */
diff --git a/scripts/prefix.c b/scripts/prefix.c
index 8b604a0..06576ae 100644
--- a/scripts/prefix.c
+++ b/scripts/prefix.c
@@ -1,7 +1,6 @@
 
 /* prefix.c - generate an unprefixed symbol list
  *
- * Last changed in libpng version 1.6.16 [December 22, 2014]
  * Copyright (c) 2013-2014 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
diff --git a/scripts/smakefile.ppc b/scripts/smakefile.ppc
index 2e7380b..9212d2f 100644
--- a/scripts/smakefile.ppc
+++ b/scripts/smakefile.ppc
@@ -11,22 +11,21 @@
            OPTLOOP OPTRDEP=8 OPTDEP=8 OPTCOMP=8
 LIBNAME  = libpng.a
 AR       = ppc-amigaos-ar
-AR_FLAGS = cr
+ARFLAGS  = cr
 RANLIB   = ppc-amigaos-ranlib
 LDFLAGS  = -r -o
 LDLIBS   =  ../zlib/libzip.a LIB:scppc.a
 LN       = ppc-amigaos-ld
 RM       = delete quiet
-MKDIR    = makedir
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o pngread.o \
-       pngerror.o pngpread.o pngwrite.o pngrtran.o pngwtran.o pngrio.o \
-       pngwio.o pngmem.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 all: $(LIBNAME) pngtest
 
 $(LIBNAME): $(OBJS)
-            $(AR) $(AR_FLAGS) $@ $(OBJS)
+            $(AR) $(ARFLAGS) $@ $(OBJS)
             $(RANLIB) $@
 
 pngtest: pngtest.o $(LIBNAME)
diff --git a/scripts/sym.c b/scripts/sym.c
index ea9e4c5..7571de2 100644
--- a/scripts/sym.c
+++ b/scripts/sym.c
@@ -1,7 +1,6 @@
 
 /* sym.c - define format of libpng.sym
  *
- * Last changed in libpng version 1.6.16 [December 22, 2014]
  * Copyright (c) 2011-2014 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
diff --git a/scripts/symbols.c b/scripts/symbols.c
index 28b841d..d51a830 100644
--- a/scripts/symbols.c
+++ b/scripts/symbols.c
@@ -1,7 +1,6 @@
 
 /* symbols.c - find all exported symbols
  *
- * Last changed in libpng version 1.6.16 [December 22, 2014]
  * Copyright (c) 2011-2014 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
diff --git a/scripts/travis.sh b/scripts/travis.sh
deleted file mode 100755
index 7d59b24..0000000
--- a/scripts/travis.sh
+++ /dev/null
@@ -1,37 +0,0 @@
-#!/bin/bash
-
-set -e
-
-if [[ $ENABLE_SANITIZERS ]]; then
-    LOCAL_CMAKE_EXTRA_ARGS="-DCMAKE_C_FLAGS=-fsanitize=$ENABLE_SANITIZERS"
-    LOCAL_MAKE_EXTRA_ARGS="CFLAGS=-fsanitize=$ENABLE_SANITIZERS LDFLAGS=-fsanitize=$ENABLE_SANITIZERS"
-fi
-
-if [[ $USE_CMAKE ]]; then
-    echo "$0: using cmake + make:" $LOCAL_CMAKE_EXTRA_ARGS $EXTRA_ARGS
-    mkdir build-cmake
-    cd build-cmake
-    cmake $LOCAL_CMAKE_EXTRA_ARGS $EXTRA_ARGS ..
-    make
-    [[ $DISABLE_TESTS ]] || make test
-    make clean
-fi
-
-if [[ $USE_CONFIGURE ]]; then
-    mkdir build-configure
-    cd build-configure
-    echo "$0: using configure + make:" $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS
-    ../configure $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS
-    make
-    [[ $DISABLE_TESTS ]] || make test
-    make clean
-    make distclean
-fi
-
-if [[ $USE_LEGACY_MAKEFILES ]]; then
-    echo "$0: using scripts/makefile.$CC:" $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS
-    make -f scripts/makefile.$CC $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS
-    [[ $DISABLE_TESTS ]] || make -f scripts/makefile.$CC $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS test
-    make -f scripts/makefile.$CC $LOCAL_MAKE_EXTRA_ARGS $EXTRA_ARGS clean
-    # TODO: use scripts/makefile.std, etc.
-fi
diff --git a/scripts/vers.c b/scripts/vers.c
index de73197..d749726 100644
--- a/scripts/vers.c
+++ b/scripts/vers.c
@@ -1,7 +1,6 @@
 
 /* vers.c - define format of libpng.vers
  *
- * Last changed in libpng version 1.6.16 [December 22, 2014]
  * Copyright (c) 2011-2014 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
diff --git a/test-driver b/test-driver
index b8521a4..be73b80 100755
--- a/test-driver
+++ b/test-driver
@@ -3,7 +3,7 @@
 
 scriptversion=2018-03-07.03; # UTC
 
-# Copyright (C) 2011-2018 Free Software Foundation, Inc.
+# Copyright (C) 2011-2021 Free Software Foundation, Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -42,11 +42,13 @@
 {
   cat <<END
 Usage:
-  test-driver --test-name=NAME --log-file=PATH --trs-file=PATH
-              [--expect-failure={yes|no}] [--color-tests={yes|no}]
-              [--enable-hard-errors={yes|no}] [--]
+  test-driver --test-name NAME --log-file PATH --trs-file PATH
+              [--expect-failure {yes|no}] [--color-tests {yes|no}]
+              [--enable-hard-errors {yes|no}] [--]
               TEST-SCRIPT [TEST-SCRIPT-ARGUMENTS]
+
 The '--test-name', '--log-file' and '--trs-file' options are mandatory.
+See the GNU Automake documentation for information.
 END
 }
 
@@ -103,8 +105,11 @@
 trap "st=141; $do_exit" 13
 trap "st=143; $do_exit" 15
 
-# Test script is run here.
-"$@" >$log_file 2>&1
+# Test script is run here. We create the file first, then append to it,
+# to ameliorate tests themselves also writing to the log file. Our tests
+# don't, but others can (automake bug#35762).
+: >"$log_file"
+"$@" >>"$log_file" 2>&1
 estatus=$?
 
 if test $enable_hard_errors = no && test $estatus -eq 99; then
@@ -126,7 +131,7 @@
 # know whether the test passed or failed simply by looking at the '.log'
 # file, without the need of also peaking into the corresponding '.trs'
 # file (automake bug#11814).
-echo "$res $test_name (exit status: $estatus)" >>$log_file
+echo "$res $test_name (exit status: $estatus)" >>"$log_file"
 
 # Report outcome to console.
 echo "${col}${res}${std}: $test_name"
diff --git a/tests/pngtest-all b/tests/pngtest-all
index 5e96451..b4280f5 100755
--- a/tests/pngtest-all
+++ b/tests/pngtest-all
@@ -1,16 +1,107 @@
 #!/bin/sh
 
-# normal execution
+st=0        # exit status (set to 1 if a test fails)
+skipped=
+fail="**FAIL**"
+skip="**SKIP**"
+success=" SUCCESS"
+TEST(){
+   # Try to make the log file easier to read:
+   echo "=============== pngtest $* ===================="
+   ./pngtest "$@"
+   status=$?
+   case "$status" in
+       0)  test_status="$success";;
+       77) test_status="$skip"
+           skipped=1;;
+       *)  test_status="$fail"
+           st="$status";; 
+   esac
+   echo "===============$test_status $* ===================="
+   return "$status"
+}
 
-./pngtest --strict ${srcdir}/pngtest.png
+# The "standard" test
+TEST --strict "${srcdir}"/pngtest.png
 
-# various crashers
-# using --relaxed because some come from fuzzers that don't maintain CRC's
+# Various crashers
+# Use --relaxed because some come from fuzzers that don't maintain CRCs
+TEST --relaxed "${srcdir}"/contrib/testpngs/crashers/badcrc.png
+# Use --xfail because there is no reliable way of disabling these errors
+# (Adler32 checking cannot be switched off on all builds and there is no
+# provision for turning the other checks into warnings.)
+TEST --xfail "${srcdir}"/contrib/testpngs/crashers/badadler.png
+TEST --xfail "${srcdir}"/contrib/testpngs/crashers/bad_iCCP.png
+TEST --xfail "${srcdir}"/contrib/testpngs/crashers/empty_ancillary_chunks.png
+for file in "${srcdir}"/contrib/testpngs/crashers/huge_*_chunk.png
+do
+   TEST --xfail "$file"
+done
+for file in "${srcdir}"/contrib/testpngs/crashers/huge_*safe_to_copy.png
+do
+   TEST --xfail "$file"
+done
+TEST --xfail "${srcdir}"/contrib/testpngs/crashers/huge_IDAT.png
 
-./pngtest --relaxed ${srcdir}/contrib/testpngs/crashers/badcrc.png
-./pngtest --relaxed ${srcdir}/contrib/testpngs/crashers/badadler.png
-./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/bad_iCCP.png
-./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/empty_ancillary_chunks.png
-./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/huge_*_chunk.png \
-    ${srcdir}/contrib/testpngs/crashers/huge_*safe_to_copy.png
-./pngtest --xfail ${srcdir}/contrib/testpngs/crashers/huge_IDAT.png
+# Regression tests for required warnings (or errors):
+check_stdout(){
+   # $1: the test file (a bad PNG which must produce a warning, etc)
+   # $2: a string which must occur at the end of line on stdout for success
+   # result: an error message on descriptor 3 if the string is NOT found
+   #
+   # WARNING: when this script is executed on MSYS2 (Windows Cygwin variant)
+   # pngtest outputs lines terminated with <cr><lf> however the MSYS2 shell
+   # expects <lf> (\n) terminated lines so the <cr> ends up in the shell
+   # variable 'line' below.  The pattern matching ignores this because of the
+   # '*' at the end of the pattern match.
+   found=
+   skipped=
+   while read line
+   do
+      case "$line" in
+         *"$2"*) found=1;;
+         *"TEST SKIPPED"*) skipped=1;;
+      esac
+      echo "$line" # preserve the original output verbatim
+   done
+   # output the missing warning on descriptor 3:
+   test -z "$found" -a -z "$skipped" && echo "$1: $2" >&3
+}
+# NOTE: traditionally the Bourne shell executed the last element in a pipe
+# sequence in the original shell so it could set variables in the original
+# shell however this is not reliable and doesn't work in bash.
+#
+# It *is* reliable to use the actual exit status of the last command in
+# the pipeline.
+exec 4>&1 # original stdout - the log file
+{
+   exec 3>&1 # stdout is the pipe at this point
+   fail=" FAIL(EXPECTED)" # runtime scope
+   success=" SUCCESS(UNEXPECTED)" # there should be a write error
+   for file in "${srcdir}"/contrib/testpngs/badpal/*.png
+   do
+     # The exit code is ignored here, the test is that the particular errors
+     # (warnings) are produced.  The original output still ends up in the log
+     # file.
+     {
+        TEST "$file"
+        test "$?" -eq 77 && echo "TEST SKIPPED"
+     } |
+        check_stdout "$file" 'IDAT: Read palette index exceeding num_palette' |
+        check_stdout "$file" 'Wrote palette index exceeding num_palette' >&4
+   done
+   exec 3>&-
+} | {
+   # This may not be a sub-shell, if it is 'st' is undefined and the exit
+   # just ends up as 'exit'.
+   while read error
+   do
+      echo "MISSING REPORT: $error"
+      st=1
+   done
+   exit $st
+} || st=$?
+
+test "$st" -gt 0 && exit "$st"
+test -n "$skipped" && exit 77
+exit 0