[PATCH 2/2] libstdc++: Use pthread_mutex_clocklock when TSan is active [PR121496]

[Jonathan Wakely]

This reverts r14-905-g3b7cb33033fbe6 which disabled the use of
pthread_mutex_clocklock when TSan is active. That's no longer needed,
because GCC has TSan interceptors for pthread_mutex_clocklock since GCC
15.1 and Clang has them since 18.1.0 (released March 2024).

The interceptor was added by https://github.com/llvm/llvm-project/pull/75713

libstdc++-v3/ChangeLog:

	PR libstdc++/121496
	* acinclude.m4 (GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK): Do not
	use _GLIBCXX_TSAN in _GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK macro.
	* configure: Regenerate.
---

Tested x86_64-linux.

We could backport this to GCC 15 but I might only do it for trunk,
because it's possible that GCC 15 headers will be used with Clang
versions older than 18.1.0 ... maybe?

 libstdc++-v3/acinclude.m4 | 2 +-
 libstdc++-v3/configure    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 080a4fca9b57..027735eeeb3b 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -4511,7 +4511,7 @@ AC_DEFUN([GLIBCXX_CHECK_PTHREAD_MUTEX_CLOCKLOCK], [
       [glibcxx_cv_PTHREAD_MUTEX_CLOCKLOCK=no])
   ])
   if test $glibcxx_cv_PTHREAD_MUTEX_CLOCKLOCK = yes; then
-    AC_DEFINE(_GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK, (_GLIBCXX_TSAN==0), [Define if pthread_mutex_clocklock is available in <pthread.h>.])
+    AC_DEFINE(_GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK, 1, [Define if pthread_mutex_clocklock is available in <pthread.h>.])
   fi
 
   CXXFLAGS="$ac_save_CXXFLAGS"
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 4ad781a4b6e4..d57cfd581adc 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -21881,7 +21881,7 @@ fi
 $as_echo "$glibcxx_cv_PTHREAD_MUTEX_CLOCKLOCK" >&6; }
   if test $glibcxx_cv_PTHREAD_MUTEX_CLOCKLOCK = yes; then
 
-$as_echo "#define _GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK (_GLIBCXX_TSAN==0)" >>confdefs.h
+$as_echo "#define _GLIBCXX_USE_PTHREAD_MUTEX_CLOCKLOCK 1" >>confdefs.h
 
   fi
 
-- 
2.50.1