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

[Stefan Liebler]

On 4/1/25 17:08, H.J. Lu wrote:
> On Tue, Apr 1, 2025 at 7:59 AM Sam James <sam@gentoo.org> wrote:
>>
>> Andreas Schwab <schwab@suse.de> writes:
>>
>>> On Feb 12 2025, H.J. Lu wrote:
>>>
>>>> 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
>>>>  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
>>>> -
>>>
>>> You cannot remove that, it has nothing to do with the compiler version.
>>>
>>> /home/abuild/rpmbuild/BUILD/glibc-testsuite-src-2.41.9000.228.gc6e289569-build/glibc-2.41.9000.228.gc6e289569/cc-base/math/test-tgmath3-atan2.c: In function ‘test_atan2_132’:
>>> /home/abuild/rpmbuild/BUILD/glibc-testsuite-src-2.41.9000.228.gc6e289569-build/glibc-2.41.9000.228.gc6e289569/cc-base/math/test-tgmath3-atan2.c:1247:66:
>>> error: conflicting types for ‘var_long_double_Float64x’; have
>>> ‘_Float64x’
>>>  1247 |   extern typeof (atan2 (vol_var_long_double, vol_var__Float64x)) var_long_double_Float64x __attribute__ ((unused));
>>>       |                                                                  ^~~~~~~~~~~~~~~~~~~~~~~~
>>> /home/abuild/rpmbuild/BUILD/glibc-testsuite-src-2.41.9000.228.gc6e289569-build/glibc-2.41.9000.228.gc6e289569/cc-base/math/test-tgmath3-atan2.c:179:22:
>>> note: previous declaration of ‘var_long_double_Float64x’ with type
>>> ‘long_double_Float64x’ {aka ‘long double’}
>>>   179 | long_double_Float64x var_long_double_Float64x __attribute__ ((unused));
>>>       |                      ^~~~~~~~~~~~~~~~~~~~~~~~
>>> make[2]: *** [../o-iterator.mk:9: /home/abuild/rpmbuild/BUILD/glibc-testsuite-src-2.41.9000.228.gc6e289569-build/glibc-2.41.9000.228.gc6e289569/cc-base/math/test-tgmath3-atan2.o] Error 1
>>
>> I suspect I didn't notice when reviewing again as I assumed it was the
>> same as the cleanup in
>> https://inbox.sourceware.org/libc-alpha/87ikqk2yr0.fsf@gentoo.org/.
>>
>> H.J., do you want me to test & fix it?
> 
> Please do.
> 
> Thanks.
> 
As it seems you are posting a further patch, can you please also adjust
NEWS with something like this for the next release:
 Changes to build and runtime requirements:

-  [Add changes to build and runtime requirements here]
+* GCC 12.1 or later is now required to build the GNU C Library.

Thanks,
Stefan