]> git.ipfire.org Git - thirdparty/gcc.git/commit
libstdc++: Do not use pthread_mutex_clocklock with ThreadSanitizer
authorJonathan Wakely <jwakely@redhat.com>
Tue, 9 May 2023 08:30:48 +0000 (09:30 +0100)
committerJonathan Wakely <jwakely@redhat.com>
Tue, 16 May 2023 08:59:01 +0000 (09:59 +0100)
commit3b7cb33033fbe6af6c1c4ef014f7353479d1dd6b
tree5fa4d0e49ee40aaed8bfe46325a6cf8406eb554b
parent45efdda3ff6c92f948881298031779f81aad0886
libstdc++: Do not use pthread_mutex_clocklock with ThreadSanitizer

As noted in https://github.com/llvm/llvm-project/issues/62623 there are
no tsan interceptors for some of the new POSIX-1:202x APIs added by
https://austingroupbugs.net/view.php?id=1216 so tsan gives false
positive warnings for try_lock_for on timed mutexes.

Disable the uses of the new pthread_mutex_clocklock API when tsan is
active. This changes the semantics of the try_lock_for functions,
because it can change which clock is used for the wait. This means those
functions might be affected by system clock adjustments when tsan is
used, when they would not be affected otherwise.

Reviewed-by: Thomas Rodgers <trodgers@redhat.com>
Reviewed-by: Mike Crowe <mac@mcrowe.com>
libstdc++-v3/ChangeLog:

* acinclude.m4 (GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK): Define
_GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK in terms of _GLIBCXX_TSAN.
* configure: Regenerate.
libstdc++-v3/acinclude.m4
libstdc++-v3/configure