Raise the minimum GCC version to 11.5 [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 2.41:

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 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 11.5 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
11.5 or newer, they should build and install GCC 11.5 or newer to work
on glibc.

This fixes BZ #32539.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
---
 INSTALL                                      | 25 +-----
 configure                                    |  3 +-
 configure.ac                                 |  3 +-
 manual/install.texi                          | 24 +-----
 sysdeps/s390/configure                       | 40 ----------
 sysdeps/s390/configure.ac                    | 18 -----
 sysdeps/unix/sysv/linux/powerpc/configure    | 83 --------------------
 sysdeps/unix/sysv/linux/powerpc/configure.ac | 34 --------
 8 files changed, 11 insertions(+), 219 deletions(-)
  

"H.J. Lu" <hjl.tools@gmail.com> writes:

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

I will look at it later today. Thanks.
  

"H.J. Lu" <hjl.tools@gmail.com> writes:

> 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 2.41:
>
> 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 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 11.5 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
> 11.5 or newer, they should build and install GCC 11.5 or newer to work
> on glibc.
>
> This fixes BZ #32539.
>
> Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> ---
>  INSTALL                                      | 25 +-----
>  configure                                    |  3 +-
>  configure.ac                                 |  3 +-
>  manual/install.texi                          | 24 +-----
>  sysdeps/s390/configure                       | 40 ----------
>  sysdeps/s390/configure.ac                    | 18 -----
>  sysdeps/unix/sysv/linux/powerpc/configure    | 83 --------------------
>  sysdeps/unix/sysv/linux/powerpc/configure.ac | 34 --------
>  8 files changed, 11 insertions(+), 219 deletions(-)
>
> diff --git a/INSTALL b/INSTALL
> index 7e8dcbb089..d0ae89e625 100644
> --- a/INSTALL
> +++ b/INSTALL
> @@ -488,31 +488,14 @@ build the GNU C Library:
>       As of release time, GNU 'make' 4.4.1 is the newest verified to work
>       to build the GNU C Library.
>  
> -   * GCC 6.2 or newer
> +   * GCC 11.5 or newer
>  
> -     GCC 6.2 or higher is required.  In general it is recommended to use
> -     the newest version of the compiler that is known to work for
> +     GCC 11.5 or higher is required.  In general it is recommended to
> +     use the newest version of the compiler that is known to work for
>       building the GNU C Library, as newer compilers usually produce
> -     better code.  As of release time, GCC 14.1 is the newest compiler
> +     better code.  As of release time, GCC 14.2 is the newest compiler
>       verified to work to build the GNU C Library.
>  
> -     For PowerPC 64-bits little-endian (powerpc64le), a GCC version with
> -     support for '-mno-gnu-attribute', '-mabi=ieeelongdouble', and
> -     '-mabi=ibmlongdouble' is required.  Likewise, the compiler must
> -     also support passing '-mlong-double-128' with the preceding
> -     options.  As of release, this implies GCC 7.4 and newer (excepting
> -     GCC 7.5.0, see GCC PR94200).  These additional features are
> -     required for building the GNU C Library with support for IEEE long
> -     double.
> -
> -     For ARC architecture builds, GCC 8.3 or higher is needed.
> -
> -     For s390x architecture builds, GCC 7.1 or higher is needed (See gcc
> -     Bug 98269).
> -
> -     For AArch64 architecture builds with mathvec enabled, GCC 10 or
> -     higher is needed due to dependency on arm_sve.h.
> -
>       For multi-arch support it is recommended to use a GCC which has
>       been built with support for GNU indirect functions.  This ensures
>       that correct debugging information is generated for functions
> diff --git a/configure b/configure
> index eb8abd0054..32c18b2eda 100755
> --- a/configure
> +++ b/configure
> @@ -5763,6 +5763,7 @@ if test $ac_verc_fail = yes; then
>  fi
>  
>  
> +# Require GCC 11.5 to build.
>  { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if $CC is sufficient to build libc" >&5
>  printf %s "checking if $CC is sufficient to build libc... " >&6; }
>  if test ${libc_cv_compiler_ok+y}
> @@ -5777,7 +5778,7 @@ int
>  main (void)
>  {
>  
> -#if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
> +#if !defined __GNUC__ || __GNUC__ < 11 || (__GNUC__ == 11 && __GNUC_MINOR__ < 5)
>  #error insufficient compiler
>  #endif
>    ;
> diff --git a/configure.ac b/configure.ac
> index 050bfa65e3..02da3638c8 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -573,9 +573,10 @@ AC_CHECK_PROG_VER(BISON, bison, --version,
>    [bison (GNU Bison) \([0-9]*\.[0-9.]*\)],
>    [2.7*|[3-9].*|[1-9][0-9]*], critic_missing="$critic_missing bison")
>  
> +# Require GCC 11.5 to build.
>  AC_CACHE_CHECK([if $CC is sufficient to build libc], libc_cv_compiler_ok, [
>  AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[
> -#if !defined __GNUC__ || __GNUC__ < 6 || (__GNUC__ == 6 && __GNUC_MINOR__ < 2)
> +#if !defined __GNUC__ || __GNUC__ < 11 || (__GNUC__ == 11 && __GNUC_MINOR__ < 5)
>  #error insufficient compiler
>  #endif]])],

Some distros like Debian often linger on e.g. X.2 and then backport
fixes. I don't know if this is a problem for 11 in reality. 

But such distributions probably won't be using trunk glibc anyway,
though people might try to develop on it.

This isn't an objection but I want to hear from someone who knows about
such distros. CC'd doko.

Personally, I don't want us to waste time investigating issues in 11.x
before .5 (and it's why I would've preferred 12+/an alive branch, but
forget about that for now). If people must use 11, they should use 11.5,
or bypass the check by setting the cache var.

>  	       [libc_cv_compiler_ok=yes],
> diff --git a/manual/install.texi b/manual/install.texi
> index b5292a976a..7d3436a1ff 100644
> --- a/manual/install.texi
> +++ b/manual/install.texi
> @@ -530,32 +530,14 @@ As of release time, GNU @code{make} 4.4.1 is the newest verified to work
>  to build @theglibc{}.
>  
>  @item
> -GCC 6.2 or newer
> +GCC 11.5 or newer
>  
> -GCC 6.2 or higher is required.  In general it is recommended to use
> +GCC 11.5 or higher is required.  In general it is recommended to use
>  the newest version of the compiler that is known to work for building
>  @theglibc{}, as newer compilers usually produce better code.  As of
> -release time, GCC 14.1 is the newest compiler verified to work to build
> +release time, GCC 14.2 is the newest compiler verified to work to build
>  @theglibc{}.
>  
> -For PowerPC 64-bits little-endian (powerpc64le), a GCC version with support
> -for @option{-mno-gnu-attribute}, @option{-mabi=ieeelongdouble}, and
> -@option{-mabi=ibmlongdouble} is required.  Likewise, the compiler must also
> -support passing @option{-mlong-double-128} with the preceding options.  As
> -of release, this implies GCC 7.4 and newer (excepting GCC 7.5.0, see GCC
> -PR94200).  These additional features are required for building the GNU C
> -Library with support for IEEE long double.
> -
> -@c powerpc64le performs an autoconf test to verify the compiler compiles with
> -@c commands like "$CC -c foo.c -mabi=ibmlongdouble -mlong-double-128".
> -
> -For ARC architecture builds, GCC 8.3 or higher is needed.
> -
> -For s390x architecture builds, GCC 7.1 or higher is needed (See gcc Bug 98269).
> -
> -For AArch64 architecture builds with mathvec enabled, GCC 10 or higher is needed
> -due to dependency on arm_sve.h.
> -
>  For multi-arch support it is recommended to use a GCC which has been built with
>  support for GNU indirect functions.  This ensures that correct debugging
>  information is generated for functions selected by IFUNC resolvers.  This
> diff --git a/sysdeps/s390/configure b/sysdeps/s390/configure
> index 67c3755c16..97f52524fb 100644
> --- a/sysdeps/s390/configure
> +++ b/sysdeps/s390/configure
> @@ -309,46 +309,6 @@ then
>  
>  fi
>  
> -
> -
> -{ printf "%s\n" "$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 89c3e5b211..496866b850 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([
>  *** $critic_missing])
> diff --git a/sysdeps/unix/sysv/linux/powerpc/configure b/sysdeps/unix/sysv/linux/powerpc/configure
> index 61ae675c1a..6fa7589530 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/configure
> +++ b/sysdeps/unix/sysv/linux/powerpc/configure
> @@ -1,89 +1,6 @@
>  # This file is generated from configure.ac by Autoconf.  DO NOT EDIT!
>   # Local configure fragment for sysdeps/unix/sysv/linux/powerpc/.
>  
> -
> -{ printf "%s\n" "$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 8d2ec60f68..bcf0c62442 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

We should cleanup:
* libc_cv_compiler_powerpc64le_ice (powerpc)
* soft_float_abi_support (csky)
* libc_cv_gcc_builtin_tbegin (s390, obsolete with compilers containing r6-2660-gc914ac45c7670c)

BUT if you want to defer those cleanups to after the release, to avoid
risk on targets that are harder to test, I (or you) can do that. Andreas?

> [...]

The patch looks good but we should decide on either:
1) merging with bare-minimum cleanups (maybe just top-level
configure.ac), more cleanups post-release
2) merging this as-is for now, more cleanups post-release
3) merging this with no cleanups inside, all cleanups post-release
  

Am Sonntag, 12. Januar 2025, 10:00:03 Mitteleuropäische Normalzeit schrieb Sam James:
> "H.J. Lu" <hjl.tools@gmail.com> writes:
> 
> > 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 2.41:
> >
> > 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 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 11.5 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
> > 11.5 or newer, they should build and install GCC 11.5 or newer to work
> > on glibc.
> >
> > This fixes BZ #32539.
> >
> > Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
> > ---
> >  INSTALL                                      | 25 +-----
> >  configure                                    |  3 +-
> >  configure.ac                                 |  3 +-
[...]

I think in terms of cleanups the current version is a decent compromise for
the release. Afterwards we can take care of the rest.

> 
> We should cleanup:
> * libc_cv_compiler_powerpc64le_ice (powerpc)
> * soft_float_abi_support (csky)
> * libc_cv_gcc_builtin_tbegin (s390, obsolete with compilers containing r6-2660-gc914ac45c7670c)
> 
> BUT if you want to defer those cleanups to after the release, to avoid
> risk on targets that are harder to test, I (or you) can do that. Andreas?
> 
> > [...]
> 
> The patch looks good but we should decide on either:
> 1) merging with bare-minimum cleanups (maybe just top-level
> configure.ac), more cleanups post-release
> 2) merging this as-is for now, more cleanups post-release
> 3) merging this with no cleanups inside, all cleanups post-release
>
  

On 2025-01-12 09:00, Sam James wrote:
> Some distros like Debian often linger on e.g. X.2 and then backport
> fixes. I don't know if this is a problem for 11 in reality. 

Fixes are backported indeed backported regularly in between minor
releases, but minor releases are still uploaded regularly. For instance
GCC 11 in Debian Sid is at 11.5, while it is at 11.3 in Debian
Bookworm.

> But such distributions probably won't be using trunk glibc anyway,
> though people might try to develop on it.

At least from the distribution point of view 2.40 is already build with
GCC 14.2, so that's not an issue at all.

The only minor concern is that backporting patches to older stable trees
might need additional changes in some cases, but that's nothing new,
just different versions involved.

Aurelien