Remove or update updated gnulib files.

Signed-off-by: Simon Josefsson <simon@josefsson.org>
diff --git a/GNUmakefile b/GNUmakefile
index da25113..0c99d58 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -5,7 +5,7 @@
 # It is necessary if you want to build targets usually of interest
 # only to the maintainer.
 
-# Copyright (C) 2001, 2003, 2006-2019 Free Software Foundation, Inc.
+# Copyright (C) 2001, 2003, 2006-2021 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
@@ -104,7 +104,7 @@
 
 abort-due-to-no-makefile:
 	@echo There seems to be no Makefile in this directory.   1>&2
-	@echo "You must run ./configure before running 'make'." 1>&2
+	@echo "You must run ./configure before running '$(MAKE)'." 1>&2
 	@exit 1
 
 endif
diff --git a/build-aux/useless-if-before-free b/build-aux/useless-if-before-free
deleted file mode 100755
index 6ac8aa9..0000000
--- a/build-aux/useless-if-before-free
+++ /dev/null
@@ -1,226 +0,0 @@
-#!/bin/sh
-#! -*-perl-*-
-
-# Detect instances of "if (p) free (p);".
-# Likewise "if (p != 0)", "if (0 != p)", or with NULL; and with braces.
-
-# Copyright (C) 2008-2019 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
-# 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 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 <https://www.gnu.org/licenses/>.
-#
-# Written by Jim Meyering
-
-# This is a prologue that allows to run a perl script as an executable
-# on systems that are compliant to a POSIX version before POSIX:2017.
-# On such systems, the usual invocation of an executable through execlp()
-# or execvp() fails with ENOEXEC if it is a script that does not start
-# with a #! line.  The script interpreter mentioned in the #! line has
-# to be /bin/sh, because on GuixSD systems that is the only program that
-# has a fixed file name.  The second line is essential for perl and is
-# also useful for editing this file in Emacs.  The next two lines below
-# are valid code in both sh and perl.  When executed by sh, they re-execute
-# the script through the perl program found in $PATH.  The '-x' option
-# is essential as well; without it, perl would re-execute the script
-# through /bin/sh.  When executed by  perl, the next two lines are a no-op.
-eval 'exec perl -wSx "$0" "$@"'
-     if 0;
-
-my $VERSION = '2018-03-07 03:47'; # UTC
-# The definition above must lie within the first 8 lines in order
-# for the Emacs time-stamp write hook (at end) to update it.
-# If you change this file with Emacs, please let the write hook
-# do its job.  Otherwise, update this string manually.
-
-use strict;
-use warnings;
-use Getopt::Long;
-
-(my $ME = $0) =~ s|.*/||;
-
-# use File::Coda; # https://meyering.net/code/Coda/
-END {
-  defined fileno STDOUT or return;
-  close STDOUT and return;
-  warn "$ME: failed to close standard output: $!\n";
-  $? ||= 1;
-}
-
-sub usage ($)
-{
-  my ($exit_code) = @_;
-  my $STREAM = ($exit_code == 0 ? *STDOUT : *STDERR);
-  if ($exit_code != 0)
-    {
-      print $STREAM "Try '$ME --help' for more information.\n";
-    }
-  else
-    {
-      print $STREAM <<EOF;
-Usage: $ME [OPTIONS] FILE...
-
-Detect any instance in FILE of a useless "if" test before a free call, e.g.,
-"if (p) free (p);".  Any such test may be safely removed without affecting
-the semantics of the C code in FILE.  Use --name=FOO --name=BAR to also
-detect free-like functions named FOO and BAR.
-
-OPTIONS:
-
-   --list       print only the name of each matching FILE (\\0-terminated)
-   --name=N     add name N to the list of \'free\'-like functions to detect;
-                  may be repeated
-
-   --help       display this help and exit
-   --version    output version information and exit
-
-Exit status:
-
-  0   one or more matches
-  1   no match
-  2   an error
-
-EXAMPLE:
-
-For example, this command prints all removable "if" tests before "free"
-and "kfree" calls in the linux kernel sources:
-
-    git ls-files -z |xargs -0 $ME --name=kfree
-
-EOF
-    }
-  exit $exit_code;
-}
-
-sub is_NULL ($)
-{
-  my ($expr) = @_;
-  return ($expr eq 'NULL' || $expr eq '0');
-}
-
-{
-  sub EXIT_MATCH {0}
-  sub EXIT_NO_MATCH {1}
-  sub EXIT_ERROR {2}
-  my $err = EXIT_NO_MATCH;
-
-  my $list;
-  my @name = qw(free);
-  GetOptions
-    (
-     help => sub { usage 0 },
-     version => sub { print "$ME version $VERSION\n"; exit },
-     list => \$list,
-     'name=s@' => \@name,
-    ) or usage 1;
-
-  # Make sure we have the right number of non-option arguments.
-  # Always tell the user why we fail.
-  @ARGV < 1
-    and (warn "$ME: missing FILE argument\n"), usage EXIT_ERROR;
-
-  my $or = join '|', @name;
-  my $regexp = qr/(?:$or)/;
-
-  # Set the input record separator.
-  # Note: this makes it impractical to print line numbers.
-  $/ = '"';
-
-  my $found_match = 0;
- FILE:
-  foreach my $file (@ARGV)
-    {
-      open FH, '<', $file
-        or (warn "$ME: can't open '$file' for reading: $!\n"),
-          $err = EXIT_ERROR, next;
-      while (defined (my $line = <FH>))
-        {
-          # Skip non-matching lines early to save time
-          $line =~ /\bif\b/
-            or next;
-          while ($line =~
-              /\b(if\s*\(\s*([^)]+?)(?:\s*!=\s*([^)]+?))?\s*\)
-              #  1          2                  3
-               (?:   \s*$regexp\s*\((?:\s*\([^)]+\))?\s*([^)]+)\)\s*;|
-                \s*\{\s*$regexp\s*\((?:\s*\([^)]+\))?\s*([^)]+)\)\s*;\s*\}))/sxg)
-            {
-              my $all = $1;
-              my ($lhs, $rhs) = ($2, $3);
-              my ($free_opnd, $braced_free_opnd) = ($4, $5);
-              my $non_NULL;
-              if (!defined $rhs) { $non_NULL = $lhs }
-              elsif (is_NULL $rhs) { $non_NULL = $lhs }
-              elsif (is_NULL $lhs) { $non_NULL = $rhs }
-              else { next }
-
-              # Compare the non-NULL part of the "if" expression and the
-              # free'd expression, without regard to white space.
-              $non_NULL =~ tr/ \t//d;
-              my $e2 = defined $free_opnd ? $free_opnd : $braced_free_opnd;
-              $e2 =~ tr/ \t//d;
-              if ($non_NULL eq $e2)
-                {
-                  $found_match = 1;
-                  $list
-                    and (print "$file\0"), next FILE;
-                  print "$file: $all\n";
-                }
-            }
-        }
-    }
-  continue
-    {
-      close FH;
-    }
-
-  $found_match && $err == EXIT_NO_MATCH
-    and $err = EXIT_MATCH;
-
-  exit $err;
-}
-
-my $foo = <<'EOF';
-# The above is to *find* them.
-# This adjusts them, removing the unnecessary "if (p)" part.
-
-# FIXME: do something like this as an option (doesn't do braces):
-free=xfree
-git grep -l -z "$free *(" \
-  | xargs -0 useless-if-before-free -l --name="$free" \
-  | xargs -0 perl -0x3b -pi -e \
-   's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*(?:0|NULL))?\s*\)\s+('"$free"'\s*\((?:\s*\([^)]+\))?\s*\1\s*\)\s*;)/$2/s'
-
-# Use the following to remove redundant uses of kfree inside braces.
-# Note that -0777 puts perl in slurp-whole-file mode;
-# but we have plenty of memory, these days...
-free=kfree
-git grep -l -z "$free *(" \
-  | xargs -0 useless-if-before-free -l --name="$free" \
-  | xargs -0 perl -0777 -pi -e \
-     's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*(?:0|NULL))?\s*\)\s*\{\s*('"$free"'\s*\((?:\s*\([^)]+\))?\s*\1\s*\);)\s*\}[^\n]*$/$2/gms'
-
-Be careful that the result of the above transformation is valid.
-If the matched string is followed by "else", then obviously, it won't be.
-
-When modifying files, refuse to process anything other than a regular file.
-EOF
-
-## Local Variables:
-## mode: perl
-## indent-tabs-mode: nil
-## eval: (add-hook 'before-save-hook 'time-stamp)
-## time-stamp-line-limit: 50
-## time-stamp-start: "my $VERSION = '"
-## time-stamp-format: "%:y-%02m-%02d %02H:%02M"
-## time-stamp-time-zone: "UTC0"
-## time-stamp-end: "'; # UTC"
-## End:
diff --git a/build-aux/vc-list-files b/build-aux/vc-list-files
deleted file mode 100755
index af6b1c0..0000000
--- a/build-aux/vc-list-files
+++ /dev/null
@@ -1,113 +0,0 @@
-#!/bin/sh
-# List version-controlled file names.
-
-# Print a version string.
-scriptversion=2018-03-07.03; # UTC
-
-# Copyright (C) 2006-2019 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
-# 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 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 <https://www.gnu.org/licenses/>.
-
-
-# List the specified version-controlled files.
-# With no argument, list them all.  With a single DIRECTORY argument,
-# list the version-controlled files in that directory.
-
-# If there's an argument, it must be a single, "."-relative directory name.
-# cvsu is part of the cvsutils package: http://www.red-bean.com/cvsutils/
-
-postprocess=
-case $1 in
-  --help) cat <<EOF
-Usage: $0 [-C SRCDIR] [DIR...]
-
-Output a list of version-controlled files in DIR (default .), relative to
-SRCDIR (default .).  SRCDIR must be the top directory of a checkout.
-
-Options:
-  --help     print this help, then exit
-  --version  print version number, then exit
-  -C SRCDIR  change directory to SRCDIR before generating list
-
-Report bugs and patches to <bug-gnulib@gnu.org>.
-EOF
-    exit ;;
-
-  --version)
-    year=`echo "$scriptversion" | sed 's/[^0-9].*//'`
-    cat <<EOF
-vc-list-files $scriptversion
-Copyright (C) $year Free Software Foundation, Inc,
-License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
-This is free software: you are free to change and redistribute it.
-There is NO WARRANTY, to the extent permitted by law.
-EOF
-    exit ;;
-
-  -C)
-    test "$2" = . || postprocess="| sed 's|^|$2/|'"
-    cd "$2" || exit 1
-    shift; shift ;;
-esac
-
-test $# = 0 && set .
-
-for dir
-do
-  if test -d .git || test -f .git; then
-    test "x$dir" = x. \
-      && dir= sed_esc= \
-      || { dir="$dir/"; sed_esc=`echo "$dir"|env sed 's,\([\\/]\),\\\\\1,g'`; }
-    # Ignore git symlinks - either they point into the tree, in which case
-    # we don't need to visit the target twice, or they point somewhere
-    # else (often into a submodule), in which case the content does not
-    # belong to this package.
-    eval exec git ls-tree -r 'HEAD:"$dir"' \
-      \| sed -n '"s/^100[^	]*./$sed_esc/p"' $postprocess
-  elif test -d .hg; then
-    eval exec hg locate '"$dir/*"' $postprocess
-  elif test -d .bzr; then
-    test "$postprocess" = '' && postprocess="| sed 's|^\./||'"
-    eval exec bzr ls -R --versioned '"$dir"' $postprocess
-  elif test -d CVS; then
-    test "$postprocess" = '' && postprocess="| sed 's|^\./||'"
-    if test -x build-aux/cvsu; then
-      eval build-aux/cvsu --find --types=AFGM '"$dir"' $postprocess
-    elif (cvsu --help) >/dev/null 2>&1; then
-      eval cvsu --find --types=AFGM '"$dir"' $postprocess
-    else
-      eval awk -F/ \''{			\
-          if (!$1 && $3 !~ /^-/) {	\
-            f=FILENAME;			\
-            if (f ~ /CVS\/Entries$/)	\
-              f = substr(f, 1, length(f)-11); \
-            print f $2;			\
-          }}'\''				\
-        `find "$dir" -name Entries -print` /dev/null' $postprocess
-    fi
-  elif test -d .svn; then
-    eval exec svn list -R '"$dir"' $postprocess
-  else
-    echo "$0: Failed to determine type of version control used in `pwd`" 1>&2
-    exit 1
-  fi
-done
-
-# Local variables:
-# eval: (add-hook 'before-save-hook 'time-stamp)
-# time-stamp-start: "scriptversion="
-# time-stamp-format: "%:y-%02m-%02d.%02H"
-# time-stamp-time-zone: "UTC0"
-# time-stamp-end: "; # UTC"
-# End: