[runtimes] Introduce object libraries
This is a variant of D116689 rebased on top of the new (proposed) ABI
refactoring in D120727. It should conserve the basic properties of the
original patch by @phosek, except it also allows cleaning up the merging
of libc++abi into libc++ from the libc++ side.
Differential Revision: https://reviews.llvm.org/D125393
GitOrigin-RevId: aa656f6c2dec73faceeed21e15401d8f0c743c8b
diff --git a/cmake/Modules/HandleLibcxxabiFlags.cmake b/cmake/Modules/HandleLibcxxabiFlags.cmake
index 98b455c..25d4789 100644
--- a/cmake/Modules/HandleLibcxxabiFlags.cmake
+++ b/cmake/Modules/HandleLibcxxabiFlags.cmake
@@ -240,3 +240,15 @@
macro(split_list listname)
string(REPLACE ";" " " ${listname} "${${listname}}")
endmacro()
+
+# For each specified flag, add that compile flag to the provided target.
+# The flags are added with the given visibility, i.e. PUBLIC|PRIVATE|INTERFACE.
+function(target_add_compile_flags_if_supported target visibility)
+ foreach(flag ${ARGN})
+ mangle_name("${flag}" flagname)
+ check_cxx_compiler_flag("${flag}" "CXX_SUPPORTS_${flagname}_FLAG")
+ if (CXX_SUPPORTS_${flagname}_FLAG)
+ target_compile_options(${target} ${visibility} ${flag})
+ endif()
+ endforeach()
+endfunction()
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 2ce8dd8..e19f33c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -77,32 +77,13 @@
add_library_flags_if(LIBCXXABI_HAS_C_LIB c)
endif()
-if (LIBCXXABI_USE_COMPILER_RT)
- find_compiler_rt_library(builtins LIBCXXABI_BUILTINS_LIBRARY)
- list(APPEND LIBCXXABI_SHARED_LIBRARIES "${LIBCXXABI_BUILTINS_LIBRARY}")
-endif ()
-
-if (LIBCXXABI_USE_LLVM_UNWINDER)
- # Prefer using the in-tree version of libunwind, either shared or static. If
- # none are found fall back to using -lunwind.
- # FIXME: Is it correct to prefer the static version of libunwind?
- if (NOT LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_SHARED_LIBRARY AND (TARGET unwind_shared OR HAVE_LIBUNWIND))
- list(APPEND LIBCXXABI_SHARED_LIBRARIES unwind_shared)
- elseif (LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_SHARED_LIBRARY AND (TARGET unwind_static OR HAVE_LIBUNWIND))
- list(APPEND LIBCXXABI_SHARED_LIBRARIES unwind_static)
- else()
- list(APPEND LIBCXXABI_SHARED_LIBRARIES unwind)
- endif()
- if (NOT LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY AND (TARGET unwind_shared OR HAVE_LIBUNWIND))
- list(APPEND LIBCXXABI_STATIC_LIBRARIES unwind_shared)
- elseif (LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY AND (TARGET unwind_static OR HAVE_LIBUNWIND))
- # We handle this by directly merging libunwind objects into libc++abi.
- else()
- list(APPEND LIBCXXABI_STATIC_LIBRARIES unwind)
- endif()
-else()
+if (NOT LIBCXXABI_USE_COMPILER_RT)
+ add_library_flags_if(LIBCXXABI_HAS_GCC_LIB gcc)
+endif()
+if (NOT LIBCXXABI_USE_LLVM_UNWINDER)
add_library_flags_if(LIBCXXABI_HAS_GCC_S_LIB gcc_s)
endif()
+
if (MINGW)
# MINGW_LIBRARIES is defined in config-ix.cmake
list(APPEND LIBCXXABI_LIBRARIES ${MINGW_LIBRARIES})
@@ -111,10 +92,6 @@
list(APPEND LIBCXXABI_LIBRARIES android_support)
endif()
-if (NOT LIBCXXABI_USE_COMPILER_RT)
- add_library_flags_if(LIBCXXABI_HAS_GCC_LIB gcc)
-endif ()
-
# Setup flags.
if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
add_link_flags_if_supported(-nostdlib++)
@@ -175,25 +152,43 @@
endif()
# Build the shared library.
-if (LIBCXXABI_ENABLE_SHARED)
- add_library(cxxabi_shared SHARED ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
- target_link_libraries(cxxabi_shared PRIVATE cxx-headers ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
- target_link_libraries(cxxabi_shared PUBLIC cxxabi-headers)
- if (TARGET pstl::ParallelSTL)
- target_link_libraries(cxxabi_shared PUBLIC pstl::ParallelSTL)
+add_library(cxxabi_shared_objects OBJECT EXCLUDE_FROM_ALL ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
+if (LIBCXXABI_USE_LLVM_UNWINDER)
+ if (LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_SHARED_LIBRARY)
+ target_sources(cxxabi_shared_objects PUBLIC $<TARGET_OBJECTS:unwind_shared_objects>)
+ else()
+ target_link_libraries(cxxabi_shared_objects PUBLIC unwind_shared)
endif()
+endif()
+target_link_libraries(cxxabi_shared_objects PRIVATE cxx-headers ${LIBCXXABI_BUILTINS_LIBRARY} ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+target_link_libraries(cxxabi_shared_objects PUBLIC cxxabi-headers)
+set_target_properties(cxxabi_shared_objects
+ PROPERTIES
+ CXX_EXTENSIONS OFF
+ CXX_STANDARD 20
+ CXX_STANDARD_REQUIRED OFF
+ COMPILE_FLAGS "${LIBCXXABI_COMPILE_FLAGS}"
+ DEFINE_SYMBOL ""
+)
+if (CMAKE_POSITION_INDEPENDENT_CODE OR NOT DEFINED CMAKE_POSITION_INDEPENDENT_CODE)
+ set_target_properties(cxxabi_shared_objects PROPERTIES POSITION_INDEPENDENT_CODE ON) # must set manually because it's an object library
+endif()
+
+if (LIBCXXABI_ENABLE_SHARED)
+ add_library(cxxabi_shared SHARED)
set_target_properties(cxxabi_shared
PROPERTIES
- CXX_EXTENSIONS OFF
- CXX_STANDARD 20
- CXX_STANDARD_REQUIRED OFF
- COMPILE_FLAGS "${LIBCXXABI_COMPILE_FLAGS}"
LINK_FLAGS "${LIBCXXABI_LINK_FLAGS}"
OUTPUT_NAME "c++abi"
SOVERSION "1"
VERSION "${LIBCXXABI_LIBRARY_VERSION}"
- DEFINE_SYMBOL ""
)
+ target_link_libraries(cxxabi_shared
+ PUBLIC cxxabi_shared_objects
+ PRIVATE ${LIBCXXABI_SHARED_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+ if (TARGET pstl::ParallelSTL)
+ target_link_libraries(cxxabi_shared PUBLIC pstl::ParallelSTL)
+ endif()
list(APPEND LIBCXXABI_BUILD_TARGETS "cxxabi_shared")
if (LIBCXXABI_INSTALL_SHARED_LIBRARY)
@@ -231,61 +226,55 @@
endif()
# Build the static library.
+add_library(cxxabi_static_objects OBJECT EXCLUDE_FROM_ALL ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
+if (LIBCXXABI_USE_LLVM_UNWINDER AND LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
+ target_sources(cxxabi_static_objects PUBLIC $<TARGET_OBJECTS:unwind_static_objects>)
+endif()
+target_link_libraries(cxxabi_static_objects PRIVATE cxx-headers ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+target_link_libraries(cxxabi_static_objects PUBLIC cxxabi-headers)
+set_target_properties(cxxabi_static_objects
+ PROPERTIES
+ CXX_EXTENSIONS OFF
+ CXX_STANDARD 20
+ CXX_STANDARD_REQUIRED OFF
+ COMPILE_FLAGS "${LIBCXXABI_COMPILE_FLAGS}"
+)
+
+if(LIBCXXABI_HERMETIC_STATIC_LIBRARY)
+ target_add_compile_flags_if_supported(cxxabi_static_objects PRIVATE -fvisibility=hidden)
+ # If the hermetic library doesn't define the operator new/delete functions
+ # then its code shouldn't declare them with hidden visibility. They might
+ # actually be provided by a shared library at link time.
+ if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
+ target_add_compile_flags_if_supported(cxxabi_static_objects PRIVATE -fvisibility-global-new-delete-hidden)
+ endif()
+ target_compile_definitions(cxxabi_static_objects
+ PRIVATE
+ _LIBCXXABI_DISABLE_VISIBILITY_ANNOTATIONS
+ _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+endif()
+
if (LIBCXXABI_ENABLE_STATIC)
- add_library(cxxabi_static STATIC ${LIBCXXABI_SOURCES} ${LIBCXXABI_HEADERS})
- target_link_libraries(cxxabi_static PRIVATE cxx-headers ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
- target_link_libraries(cxxabi_static PUBLIC cxxabi-headers)
- if (TARGET pstl::ParallelSTL)
- target_link_libraries(cxxabi_static PUBLIC pstl::ParallelSTL)
+ add_library(cxxabi_static STATIC)
+ if (LIBCXXABI_USE_LLVM_UNWINDER AND NOT LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
+ target_link_libraries(cxxabi_static PUBLIC unwind_static)
endif()
set_target_properties(cxxabi_static
PROPERTIES
- CXX_EXTENSIONS OFF
- CXX_STANDARD 20
- CXX_STANDARD_REQUIRED OFF
- COMPILE_FLAGS "${LIBCXXABI_COMPILE_FLAGS}"
LINK_FLAGS "${LIBCXXABI_LINK_FLAGS}"
OUTPUT_NAME "c++abi"
)
-
- if(LIBCXXABI_HERMETIC_STATIC_LIBRARY)
- append_flags_if_supported(CXXABI_STATIC_LIBRARY_FLAGS -fvisibility=hidden)
- # If the hermetic library doesn't define the operator new/delete functions
- # then its code shouldn't declare them with hidden visibility. They might
- # actually be provided by a shared library at link time.
- if (LIBCXXABI_ENABLE_NEW_DELETE_DEFINITIONS)
- append_flags_if_supported(CXXABI_STATIC_LIBRARY_FLAGS -fvisibility-global-new-delete-hidden)
- endif()
- target_compile_options(cxxabi_static PRIVATE ${CXXABI_STATIC_LIBRARY_FLAGS})
- target_compile_definitions(cxxabi_static
- PRIVATE
- _LIBCXXABI_DISABLE_VISIBILITY_ANNOTATIONS
- _LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+ target_link_libraries(cxxabi_static
+ PUBLIC cxxabi_static_objects
+ PRIVATE ${LIBCXXABI_STATIC_LIBRARIES} ${LIBCXXABI_LIBRARIES})
+ if (TARGET pstl::ParallelSTL)
+ target_link_libraries(cxxabi_static PUBLIC pstl::ParallelSTL)
endif()
list(APPEND LIBCXXABI_BUILD_TARGETS "cxxabi_static")
if (LIBCXXABI_INSTALL_STATIC_LIBRARY)
list(APPEND LIBCXXABI_INSTALL_TARGETS "cxxabi_static")
endif()
-
- if (APPLE)
- set(MERGE_ARCHIVES_LIBTOOL "--use-libtool" "--libtool" "${CMAKE_LIBTOOL}")
- endif()
-
- # Merge the libc++abi.a and libunwind.a into one.
- if(LIBCXXABI_USE_LLVM_UNWINDER AND LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY)
- add_custom_command(TARGET cxxabi_static POST_BUILD
- COMMAND ${Python3_EXECUTABLE} ${LIBCXXABI_LIBCXX_PATH}/utils/merge_archives.py
- ARGS
- -o "$<TARGET_LINKER_FILE:cxxabi_static>"
- --ar "${CMAKE_AR}"
- ${MERGE_ARCHIVES_LIBTOOL}
- "$<TARGET_LINKER_FILE:cxxabi_static>"
- "$<TARGET_LINKER_FILE:unwind_static>"
- WORKING_DIRECTORY ${LIBCXXABI_BUILD_DIR}
- DEPENDS unwind_static
- )
- endif()
endif()
# Add a meta-target for both libraries.
