https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112858
--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Alexandre Oliva <aol...@gcc.gnu.org>: https://gcc.gnu.org/g:3d0f3382fa7b5677f35a9becf75ac436cd7eda7b commit r14-6261-g3d0f3382fa7b5677f35a9becf75ac436cd7eda7b Author: Alexandre Oliva <ol...@adacore.com> Date: Thu Dec 7 00:38:14 2023 -0300 libsupc++: try cxa_thread_atexit_impl at runtime g++.dg/tls/thread_local-order2.C fails when the toolchain is built for a platform that lacks __cxa_thread_atexit_impl, even if the program is built and run using that toolchain on a (later) platform that offers __cxa_thread_atexit_impl. This patch adds runtime testing for __cxa_thread_atexit_impl on select platforms (GNU variants, for starters) that support weak symbols. for libstdc++-v3/ChangeLog PR libstdc++/112858 * config/os/gnu-linux/os_defines.h (_GLIBCXX_MAY_HAVE___CXA_THREAD_ATEXIT_IMPL): Define. * libsupc++/atexit_thread.cc [__GXX_WEAK__ && _GLIBCXX_MAY_HAVE___CXA_THREAD_ATEXIT_IMPL] (__cxa_thread_atexit): Add dynamic detection of __cxa_thread_atexit_impl.