Re: glibc 2.29: Reminder, only ~3 weeks to freeze!

[Romain Naour <romain dot naour at gmail dot com>]

Hi All,

Le 13/12/2018 à 23:26, Romain Naour a écrit :
> Hi Carlos, All,
> 
> Le 11/12/2018 à 17:48, Carlos O'Donell a écrit :
>> Community,
>>
>> This is a reminder that we have only ~3 weeks to the ABI freeze.
>>
>> January is the month where we stabilize everything.
>>
>> Feburary 1st is the release for 2.29.
>>
>> https://sourceware.org/glibc/wiki/Release/2.29
> 
> I did a test build using glibc [1], binutils 2.31.1, gcc 8.2, kernel-headers
> 4.14 and gdb 8.1.1 for several architectures [2].
> 
> I had a small build issue with gdb <= 8.1 due to commit [3].
> The build is fixed by backporting the patch [4] from gdb 8.2 to previous version.

Actually there is a regression when the toolchain is built with glibc 2.29 and
gcc 4.9 (when USE_ATOMIC_COMPILER_BUILTINS is not defined):

In file included from ../sysdeps/nptl/internaltypes.h:23:0,
                 from ./pthreadP.h:30,
                 from pthread_mutex_getprioceiling.c:21:
pthread_mutex_getprioceiling.c: In function 'pthread_mutex_getprioceiling':
../include/atomic.h:672:4: error: read-only variable '__atg100_val' used as
'asm' output
    __asm ("" : "=r" (__atg100_val) : "0" (*(mem)));         \
    ^
pthread_mutex_getprioceiling.c:29:26: note: in expansion of macro
'atomic_load_relaxed'
   if (__builtin_expect ((atomic_load_relaxed (&(mutex->__data.__kind))
                          ^
The issue has been introduced by:
https://github.com/bminor/glibc/commit/403b4feb22dcbc85ace72a361d2a951380372471

Best regards,
Romain

> 
> Best regards,
> Romain
> 
> [1] https://github.com/bminor/glibc/commit/89983cb37c9319806a551e8fe9f3a11ff8f973e1
> [2] https://gitlab.com/kubu93/toolchains-builder/pipelines/40073241
> [3] https://github.com/bminor/glibc/commit/89983cb37c9319806a551e8fe9f3a11ff8f973e1
> [4]
> https://github.com/bminor/binutils-gdb/commit/5a6c3296a7a90694ad4042f6256f3da6d4fa4ee8
>