[gcc r14-3661] Revert "libstdc++: Use GLIBCXX_CHECK_LINKER_FEATURES for cross-builds (PR111238)"

[gcc r14-3661] Revert "libstdc++: Use GLIBCXX_CHECK_LINKER_FEATURES for cross-builds (PR111238)"

[Christophe Lyon]

https://gcc.gnu.org/g:084a7cf9fb2d9cb98dfbe7d91602c840ec50b002

commit r14-3661-g084a7cf9fb2d9cb98dfbe7d91602c840ec50b002
Author: Christophe Lyon <christophe.lyon@linaro.org>
Date:   Fri Sep 1 07:19:48 2023 +0000

    Revert "libstdc++: Use GLIBCXX_CHECK_LINKER_FEATURES for cross-builds (PR111238)"
    
    This reverts commit 46c2e94ca66ed9991c45a6ba6204ed02869efc39.

Diff:
---
 libstdc++-v3/configure    | 154 ----------------------------------------------
 libstdc++-v3/configure.ac |   4 --
 2 files changed, 158 deletions(-)

diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 830c25fe8b13..db1932300c01 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -29823,160 +29823,6 @@ else
     CANADIAN=yes
   else
     CANADIAN=no
-  fi
-
-  if test $CANADIAN = no; then
-
-  # If we're not using GNU ld, then there's no point in even trying these
-  # tests.  Check for that first.  We should have already tested for gld
-  # by now (in libtool), but require it now just to be safe...
-  test -z "$SECTION_LDFLAGS" && SECTION_LDFLAGS=''
-  test -z "$OPT_LDFLAGS" && OPT_LDFLAGS=''
-
-
-
-  # The name set by libtool depends on the version of libtool.  Shame on us
-  # for depending on an impl detail, but c'est la vie.  Older versions used
-  # ac_cv_prog_gnu_ld, but now it's lt_cv_prog_gnu_ld, and is copied back on
-  # top of with_gnu_ld (which is also set by --with-gnu-ld, so that actually
-  # makes sense).  We'll test with_gnu_ld everywhere else, so if that isn't
-  # set (hence we're using an older libtool), then set it.
-  if test x${with_gnu_ld+set} != xset; then
-    if test x${ac_cv_prog_gnu_ld+set} != xset; then
-      # We got through "ac_require(ac_prog_ld)" and still not set?  Huh?
-      with_gnu_ld=no
-    else
-      with_gnu_ld=$ac_cv_prog_gnu_ld
-    fi
-  fi
-
-  # Start by getting the version number.  I think the libtool test already
-  # does some of this, but throws away the result.
-  glibcxx_ld_is_gold=no
-  glibcxx_ld_is_mold=no
-  if test x"$with_gnu_ld" = x"yes"; then
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ld version" >&5
-$as_echo_n "checking for ld version... " >&6; }
-
-    if $LD --version 2>/dev/null | grep 'GNU gold' >/dev/null 2>&1; then
-      glibcxx_ld_is_gold=yes
-    elif $LD --version 2>/dev/null | grep 'mold' >/dev/null 2>&1; then
-      glibcxx_ld_is_mold=yes
-    fi
-    ldver=`$LD --version 2>/dev/null |
-	   sed -e 's/[. ][0-9]\{8\}$//;s/.* \([^ ]\{1,\}\)$/\1/; q'`
-
-    glibcxx_gnu_ld_version=`echo $ldver | \
-	   $AWK -F. '{ if (NF<3) $3=0; print ($1*100+$2)*100+$3 }'`
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_gnu_ld_version" >&5
-$as_echo "$glibcxx_gnu_ld_version" >&6; }
-  fi
-
-  # Set --gc-sections.
-  glibcxx_have_gc_sections=no
-  if test "$glibcxx_ld_is_gold" = "yes" || test "$glibcxx_ld_is_mold" = "yes" ; then
-    if $LD --help 2>/dev/null | grep gc-sections >/dev/null 2>&1; then
-      glibcxx_have_gc_sections=yes
-    fi
-  else
-    glibcxx_gcsections_min_ld=21602
-    if test x"$with_gnu_ld" = x"yes" &&
-	test $glibcxx_gnu_ld_version -gt $glibcxx_gcsections_min_ld ; then
-      glibcxx_have_gc_sections=yes
-    fi
-  fi
-  if test "$glibcxx_have_gc_sections" = "yes"; then
-    # Sufficiently young GNU ld it is!  Joy and bunny rabbits!
-    # NB: This flag only works reliably after 2.16.1. Configure tests
-    # for this are difficult, so hard wire a value that should work.
-
-    ac_test_CFLAGS="${CFLAGS+set}"
-    ac_save_CFLAGS="$CFLAGS"
-    CFLAGS='-Wl,--gc-sections'
-
-    # Check for -Wl,--gc-sections
-    { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ld that supports -Wl,--gc-sections" >&5
-$as_echo_n "checking for ld that supports -Wl,--gc-sections... " >&6; }
-    if test x$gcc_no_link = xyes; then
-  as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5
-fi
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
- int one(void) { return 1; }
-     int two(void) { return 2; }
-
-int
-main ()
-{
- two();
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_link "$LINENO"; then :
-  ac_gcsections=yes
-else
-  ac_gcsections=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-    if test "$ac_gcsections" = "yes"; then
-      rm -f conftest.c
-      touch conftest.c
-      if $CC -c conftest.c; then
-	if $LD --gc-sections -o conftest conftest.o 2>&1 | \
-	   grep "Warning: gc-sections option ignored" > /dev/null; then
-	  ac_gcsections=no
-	fi
-      fi
-      rm -f conftest.c conftest.o conftest
-    fi
-    if test "$ac_gcsections" = "yes"; then
-      SECTION_LDFLAGS="-Wl,--gc-sections $SECTION_LDFLAGS"
-    fi
-    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_gcsections" >&5
-$as_echo "$ac_gcsections" >&6; }
-
-    if test "$ac_test_CFLAGS" = set; then
-      CFLAGS="$ac_save_CFLAGS"
-    else
-      # this is the suspicious part
-      CFLAGS=''
-    fi
-  fi
-
-  # Set -z,relro.
-  # Note this is only for shared objects.
-  ac_ld_relro=no
-  if test x"$with_gnu_ld" = x"yes"; then
-    # cygwin and mingw uses PE, which has no ELF relro support,
-    # multi target ld may confuse configure machinery
-    case "$host" in
-    *-*-cygwin*)
-     ;;
-    *-*-mingw*)
-     ;;
-    *)
-      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ld that supports -Wl,-z,relro" >&5
-$as_echo_n "checking for ld that supports -Wl,-z,relro... " >&6; }
-      cxx_z_relo=`$LD -v --help 2>/dev/null | grep "z relro"`
-      if test -n "$cxx_z_relo"; then
-        OPT_LDFLAGS="-Wl,-z,relro"
-        ac_ld_relro=yes
-      fi
-      { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_ld_relro" >&5
-$as_echo "$ac_ld_relro" >&6; }
-    esac
-  fi
-
-  # Set linker optimization flags.
-  if test x"$with_gnu_ld" = x"yes"; then
-    OPT_LDFLAGS="-Wl,-O1 $OPT_LDFLAGS"
-  fi
-
-
-
-
   fi
 
   # Construct crosses by hand, eliminating bits that need ld...
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index 494723534358..fc0f25220277 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -325,10 +325,6 @@ else
     CANADIAN=no
   fi
 
-  if test $CANADIAN = no; then
-    GLIBCXX_CHECK_LINKER_FEATURES
-  fi
-
   # Construct crosses by hand, eliminating bits that need ld...
   # GLIBCXX_CHECK_MATH_SUPPORT