Here issue is weakref symbol in gcc not using the __asm_ function pointed by pthread.h instead its calling directly ___pthread_cond_timedwait which is exposed by version_symbol in pthread_cond_wait.c of glibc From: Jonathan Wakely <jwakely.gcc@xxxxxxxxx> Sent: Monday, April 17, 2023 12:53 PM To: Andrew Pinski <pinskia@xxxxxxxxx> Cc: Puneet Kumar Yatnal (QUIC) <quic_puneety@xxxxxxxxxxx>; gcc-help <gcc-help@xxxxxxxxxxx>; gcc-bugs@xxxxxxxxxxx Subject: Re: Y2038: GCC gthr-posix.h weakref symbol invoking function has impact on time values WARNING: This email originated from outside of Qualcomm. Please be wary of any links or attachments, and do not enable macros. On Mon, 17 Apr 2023, 07:54 Andrew Pinski via Gcc-help, <gcc-help@xxxxxxxxxxx<mailto:gcc-help@xxxxxxxxxxx>> wrote: On Sun, Apr 16, 2023 at 10:41 PM Puneet Kumar Yatnal (QUIC) via Gcc-bugs <gcc-bugs@xxxxxxxxxxx<mailto:gcc-bugs@xxxxxxxxxxx>> wrote: > > > ++ > From: Puneet Kumar Yatnal (QUIC) > Sent: Monday, April 17, 2023 9:26 AM > To: gcc-help@xxxxxxxxxxx<mailto:gcc-help@xxxxxxxxxxx> > Subject: Y2038: GCC gthr-posix.h wekref symbol invoking function has impact on time values First gcc-bugs@ is not the right place to report a bug report as gcc-bugs is mainly for automated emails from bugzilla. Please use bugzilla first. > > All > > if we fallowed https://sourceware.org/glibc/wiki/Y2038ProofnessDesign for Y2038 fix(where all timer related variable moved to 64 bit instead of 32 bit ), pthread_cond_timedwait function from gthr_posix.h is calling different function in pthrea_cond_wait.c of glibc(due to weakref of symbol pthread_cond_timedwait()) which impacting the time value. Note libstdc++ does ABI changes too which is NOT part of that ABI design. This is where the symbol __gthread_cond_timedwait/__gthrw_pthread_cond_timedwait are used. So any changes you might do to fix __gthrw_pthread_cond_timedwait is not really going to work without wider ABI fixes to libstdc++. I don't know any one who is making those changes/fixes. So you should file an bug requesting it. And maybe even have a design document ready for it. There are many/some classes which have timespec inside them I don't think that's true. We don't use timespec members, they're just local variables, and very occasionally function parameters. and not just the mutex related ones. Thanks, Andrew > > From pthread.h > extern int pthread_cond_timedwait (pthread_cond_t *__restrict __cond, pthread_mutex_t *__restrict __mutex, const struct timespec *__restrict __abstime) __asm__ ("" "__pthread_cond_timedwait64") > > From gthread_posix.h: > static __typeof(pthread_cond_timedwait) __gthrw_pthread_cond_timedwait __attribute__ ((__weakref__("pthread_cond_timedwait"), __copy__ (pthread_cond_timedwait))); > > > __gthrw_(pthread_cond_timedwait) --> ___pthread_cond_timedwait invoking in glibc instead of __pthread_cond_timedwait64 which is impacting time value as __pthread_cond_timedwait is converting value from 32 bit to 64 bit. > > normal pthread_cond_timedwait is invoking __pthread_cond_timedwait64 properly and its working fine. > > From: pthread_cond_wait.c > > #if __TIMESIZE == 64 > strong_alias (___pthread_cond_timedwait64, ___pthread_cond_timedwait) > #else > strong_alias (___pthread_cond_timedwait64, __pthread_cond_timedwait64) > libc_hidden_def (__pthread_cond_timedwait64) > > int > ___pthread_cond_timedwait (pthread_cond_t *cond, pthread_mutex_t *mutex, > const struct timespec *abstime) > { > struct __timespec64 ts64 = valid_timespec_to_timespec64 (*abstime); > > return __pthread_cond_timedwait64 (cond, mutex, &ts64); > } > #endif /* __TIMESIZE == 64 */ > versioned_symbol (libc, ___pthread_cond_timedwait, > pthread_cond_timedwait, GLIBC_2_3_2); > libc_hidden_ver (___pthread_cond_timedwait, __pthread_cond_timedwait) > #ifndef SHARED > strong_alias (___pthread_cond_timedwait, __pthread_cond_timedwait) > #endif > > if add #defing GTHREAD_USE_WEAK 0 in libgcc/gthr-posix.h issue is resolved but that is not correct way as it disable weakref for all symbol, please let me know what is correct way to fix this, this i observed with gcc-9.3.0 gcc and glibc 2.34 > > Regards > Puneet >
