On Tue, May 24, 2016 at 9:06 AM, Rob Herring <r...@kernel.org> wrote: > On Tue, May 24, 2016 at 4:57 AM, Emil Velikov <emil.l.veli...@gmail.com> > wrote: >> From: Emil Velikov <emil.veli...@collabora.com> >> >> Add weak symbol notation for the pthread_mutexattr* symbols, thus making >> the linker happy. When building with -O1 or greater the optimiser will >> kick in and remove the said functions as they are dead/unreachable code. >> >> Ideally we'll enable the optimisations locally, yet that does not seem >> to work atm. >> >> Cc: Alejandro Piñeiro <apinhe...@igalia.com> >> Cc: Ben Widawsky <b...@bwidawsk.net> >> Cc: Ilia Mirkin <imir...@alum.mit.edu> >> Cc: Mark Janes <mark.a.ja...@intel.com> >> Cc: Rob Clark <robdcl...@gmail.com> >> Cc: Rob Herring <r...@kernel.org> >> Signed-off-by: Emil Velikov <emil.veli...@collabora.com> >> --- >> Building with -Wall -Wextra -pedantic and it does not cause any >> additional warnings/errors. >> --- >> include/c11/threads_posix.h | 26 ++++++++++++++++++++++++++ >> 1 file changed, 26 insertions(+) >> >> diff --git a/include/c11/threads_posix.h b/include/c11/threads_posix.h >> index 11d36e4..61b7fab 100644 >> --- a/include/c11/threads_posix.h >> +++ b/include/c11/threads_posix.h >> @@ -169,6 +169,32 @@ mtx_destroy(mtx_t *mtx) >> pthread_mutex_destroy(mtx); >> } >> >> +/* >> + * XXX: Workaround when building with -O0 and without pthreads link. >> + * >> + * In such cases constant folding and dead code elimination won't be >> + * available, thus the compiler will always add the pthread_mutexattr* >> + * functions into the binary. As we try to link, we'll fail as the >> + * symbols are unresolved. >> + * >> + * Ideally we'll enable the optimisations locally, yet that does not >> + * seem to work. >> + * >> + * So the alternative workaround is to annotate the symbols as weak. >> + * Thus the linker will be happy and things don't clash when building >> + * with -O1 or greater. >> + */ >> +#ifdef HAVE_FUNC_ATTRIBUTE_WEAK > > Doesn't this need to get defined somewhere?
See m4/ax_gcc_func_attribute.m4. > >> +__attribute__((weak)) >> +int pthread_mutexattr_init(pthread_mutexattr_t *attr); >> + >> +__attribute__((weak)) >> +int pthread_mutexattr_settype(pthread_mutexattr_t *attr, int type); >> + >> +__attribute__((weak)) >> +int pthread_mutexattr_destroy(pthread_mutexattr_t *attr); >> +#endif >> + >> // 7.25.4.2 >> static inline int >> mtx_init(mtx_t *mtx, int type) >> -- >> 2.8.2 >> _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
