Raise the minimum GCC version to 12.1 [BZ #32539]

For all Linux distros with glibc 2.40 which I can find, GCC 14.2 is used
to compile glibc 2.40:

OS                    GCC      URL
AOSC                  14.2.0   https://aosc.io/
Arch Linux            14.2.0   https://archlinux.org/
ArchPOWER             14.2.0   https://archlinuxpower.org/
Artix                 14.2.0   https://artixlinux.org/
Debian                14.2.0   https://www.debian.org/
Devuan                14.2.0   https://www.devuan.org/
Exherbo               14.2.0   https://www.exherbolinux.org/
Fedora                14.2.1   https://fedoraproject.org/
Gentoo                14.2.1   https://gentoo.org/
Kali Linux            14.2.0   https://www.kali.org/
KaOS                  14.2.0   https://kaosx.us/
LiGurOS               14.2.0   https://liguros.gitlab.io/
Mageia                14.2.0   https://www.mageia.org/en/
Manjaro               14.2.0   https://manjaro.org/
NixOS                 14.2.0   https://nixos.org/
openmamba             14.2.0   https://openmamba.org/
OpenMandriva          14.2.0   https://openmandriva.org/
openSUSE              14.2.0   https://www.opensuse.org/
Parabola              14.2.0   https://www.parabola.nu/
PLD Linux             14.2.0   https://pld-linux.org/
PureOS                14.2.0   https://pureos.net/
Raspbian              14.2.0   http://raspbian.org/
Slackware             14.2.0   http://www.slackware.com/
Solus                 14.2.0   https://getsol.us/
T2 SDE                14.2.0   http://t2sde.org/
Ubuntu                14.2.0   https://www.ubuntu.com/
Wikidata              14.2.0   https://wikidata.org/

Support older versions of GCC to build glibc 2.42:

1. Need to work around bugs in older versions of GCC.
2. Can't use the new features in newer versions of GCC, which may be
required for new features, like _Float16 which requires GCC 12.1 or
above, in glibc,

The main benefit of supporting older versions of GCC is easier backport
of bug fixes to the older releases of glibc, which can be mitigated by
avoiding incompatible features in newer versions of GCC for critical bug
fixes.  Require GCC 12.1 or newer to build.  Remove GCC version check for
PowerPC and s390x.

TEST_CC and TEST_CXX can be used to test the glibc build with the older
versions of GCC.

For glibc developers who are using Linux OSes which don't come with GCC
12.1 or newer, they should build and install GCC 12.1 or newer to work
on glibc.

This fixes BZ #32539.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>

4 files changed, 0 insertions, 175 deletions

diff --git a/sysdeps/s390/configure b/sysdeps/s390/configure
index 67c3755..97f5252 100644
--- a/sysdeps/s390/configure
+++ b/sysdeps/s390/configure
@@ -309,46 +309,6 @@ then
 
 fi
 
-
-
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $CC is sufficient to build libc on s390x" >&5
-printf %s "checking if $CC is sufficient to build libc on s390x... " >&6; }
-if test ${libc_cv_compiler_ok_on_s390x+y}
-then :
-  printf %s "(cached) " >&6
-else case e in #(
-  e)
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-int
-main (void)
-{
-
-#if !defined __GNUC__ || __GNUC__ < 7 || (__GNUC__ == 7 && __GNUC_MINOR__ < 1)
-#error insufficient compiler for building on s390x
-#endif
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_cpp "$LINENO"
-then :
-  libc_cv_compiler_ok_on_s390x=yes
-else case e in #(
-  e) libc_cv_compiler_ok_on_s390x=no ;;
-esac
-fi
-rm -f conftest.err conftest.i conftest.$ac_ext ;;
-esac
-fi
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_compiler_ok_on_s390x" >&5
-printf "%s\n" "$libc_cv_compiler_ok_on_s390x" >&6; }
-if test "$libc_cv_compiler_ok_on_s390x" != yes; then
-   critic_missing="$critic_missing On s390x, GCC >= 7.1.0 is required."
-fi
-
 test -n "$critic_missing" && as_fn_error $? "
 *** $critic_missing" "$LINENO" 5
 
diff --git a/sysdeps/s390/configure.ac b/sysdeps/s390/configure.ac
index 89c3e5b..496866b 100644
--- a/sysdeps/s390/configure.ac
+++ b/sysdeps/s390/configure.ac
@@ -161,23 +161,5 @@ then
   AC_DEFINE(HAVE_S390_MIN_ARCH13_ZARCH_ASM_SUPPORT)
 fi
 
-
-dnl test if GCC is new enough. See gcc "Bug 98269 - gcc 6.5.0
-dnl __builtin_add_overflow() with small uint32_t values incorrectly detects
-dnl overflow
-dnl (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98269)
-AC_CACHE_CHECK([if $CC is sufficient to build libc on s390x],
-libc_cv_compiler_ok_on_s390x, [
-AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
-#if !defined __GNUC__ || __GNUC__ < 7 || (__GNUC__ == 7 && __GNUC_MINOR__ < 1)
-#error insufficient compiler for building on s390x
-#endif
-]])],
-	[libc_cv_compiler_ok_on_s390x=yes],
-	[libc_cv_compiler_ok_on_s390x=no])])
-if test "$libc_cv_compiler_ok_on_s390x" != yes; then
-   critic_missing="$critic_missing On s390x, GCC >= 7.1.0 is required."
-fi
-
 test -n "$critic_missing" && AC_MSG_ERROR([
 *** $critic_missing])
diff --git a/sysdeps/unix/sysv/linux/powerpc/configure b/sysdeps/unix/sysv/linux/powerpc/configure
index 61ae675..6fa7589 100644
--- a/sysdeps/unix/sysv/linux/powerpc/configure
+++ b/sysdeps/unix/sysv/linux/powerpc/configure
@@ -1,89 +1,6 @@
 # This file is generated from configure.ac by Autoconf.  DO NOT EDIT!
  # Local configure fragment for sysdeps/unix/sysv/linux/powerpc/.
 
-
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC $CFLAGS -mlong-double-128 uses IBM extended format" >&5
-printf %s "checking whether $CC $CFLAGS -mlong-double-128 uses IBM extended format... " >&6; }
-if test ${libc_cv_mlong_double_128ibm+y}
-then :
-  printf %s "(cached) " >&6
-else case e in #(
-  e) save_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -mlong-double-128"
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <float.h>
-int
-main (void)
-{
-
-#if LDBL_MANT_DIG != 106
-# error "compiler doesn't implement IBM extended format of long double"
-#endif
-long double foobar (long double x) { return x; }
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"
-then :
-  libc_cv_mlong_double_128ibm=yes
-else case e in #(
-  e) libc_cv_mlong_double_128ibm=no ;;
-esac
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
-CFLAGS="$save_CFLAGS" ;;
-esac
-fi
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_mlong_double_128ibm" >&5
-printf "%s\n" "$libc_cv_mlong_double_128ibm" >&6; }
-
-if test "$libc_cv_mlong_double_128ibm" = no; then
-  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether $CC $CFLAGS supports -mabi=ibmlongdouble" >&5
-printf %s "checking whether $CC $CFLAGS supports -mabi=ibmlongdouble... " >&6; }
-if test ${libc_cv_mabi_ibmlongdouble+y}
-then :
-  printf %s "(cached) " >&6
-else case e in #(
-  e)   save_CFLAGS="$CFLAGS"
-  CFLAGS="$CFLAGS -mlong-double-128 -mabi=ibmlongdouble"
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <float.h>
-int
-main (void)
-{
-
-#if LDBL_MANT_DIG != 106
-# error "compiler doesn't implement IBM extended format of long double"
-#endif
-long double foobar (long double x) { return x; }
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"
-then :
-  libc_cv_mabi_ibmlongdouble=yes
-else case e in #(
-  e) libc_cv_mabi_ibmlongdouble=no ;;
-esac
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext
-  CFLAGS="$save_CFLAGS" ;;
-esac
-fi
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_mabi_ibmlongdouble" >&5
-printf "%s\n" "$libc_cv_mabi_ibmlongdouble" >&6; }
-
-  if test "$libc_cv_mabi_ibmlongdouble" = yes; then
-    CFLAGS="$CFLAGS -mabi=ibmlongdouble"
-  else
-    as_fn_error $? "this configuration requires -mlong-double-128 IBM extended format support" "$LINENO" 5
-  fi
-fi
-
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for linker that supports --no-tls-get-addr-optimize" >&5
 printf %s "checking for linker that supports --no-tls-get-addr-optimize... " >&6; }
 libc_linker_feature=no
diff --git a/sysdeps/unix/sysv/linux/powerpc/configure.ac b/sysdeps/unix/sysv/linux/powerpc/configure.ac
index 8d2ec60..bcf0c62 100644
--- a/sysdeps/unix/sysv/linux/powerpc/configure.ac
+++ b/sysdeps/unix/sysv/linux/powerpc/configure.ac
@@ -2,40 +2,6 @@ sinclude(./aclocal.m4)dnl Autoconf lossage
 GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
 # Local configure fragment for sysdeps/unix/sysv/linux/powerpc/.
 
-AC_CACHE_CHECK(whether $CC $CFLAGS -mlong-double-128 uses IBM extended format,
-	       libc_cv_mlong_double_128ibm, [dnl
-save_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -mlong-double-128"
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <float.h>]], [[
-#if LDBL_MANT_DIG != 106
-# error "compiler doesn't implement IBM extended format of long double"
-#endif
-long double foobar (long double x) { return x; }]])],
-	       libc_cv_mlong_double_128ibm=yes,
-	       libc_cv_mlong_double_128ibm=no)
-CFLAGS="$save_CFLAGS"])
-
-if test "$libc_cv_mlong_double_128ibm" = no; then
-  AC_CACHE_CHECK(whether $CC $CFLAGS supports -mabi=ibmlongdouble,
-		 libc_cv_mabi_ibmlongdouble, [dnl
-  save_CFLAGS="$CFLAGS"
-  CFLAGS="$CFLAGS -mlong-double-128 -mabi=ibmlongdouble"
-  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <float.h>]], [[
-#if LDBL_MANT_DIG != 106
-# error "compiler doesn't implement IBM extended format of long double"
-#endif
-long double foobar (long double x) { return x; }]])],
-		 libc_cv_mabi_ibmlongdouble=yes,
-		 libc_cv_mabi_ibmlongdouble=no)
-  CFLAGS="$save_CFLAGS"])
-
-  if test "$libc_cv_mabi_ibmlongdouble" = yes; then
-    CFLAGS="$CFLAGS -mabi=ibmlongdouble"
-  else
-    AC_MSG_ERROR([this configuration requires -mlong-double-128 IBM extended format support])
-  fi
-fi
-
 LIBC_LINKER_FEATURE([--no-tls-get-addr-optimize], [-Wl,--no-tls-get-addr-optimize],
                     [libc_cv_tls_get_addr_optimize=yes], [libc_cv_tls_get_addr_optimize=no])
 LIBC_CONFIG_VAR([have-tls-get-addr-optimize], [$libc_cv_tls_get_addr_optimize])