https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100179
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-11 branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:718fcebe8b65e98b794f9a53ce7358e034657588 commit r11-8282-g718fcebe8b65e98b794f9a53ce7358e034657588 Author: Jonathan Wakely <jwak...@redhat.com> Date: Thu Apr 22 11:10:06 2021 +0100 libstdc++: Remove #error from <semaphore> implementation [PR 100179] This removes the #error from <bits/semaphore_base.h> for the case where neither __atomic_semaphore nor __platform_semaphore is defined. Also rename the _GLIBCXX_REQUIRE_POSIX_SEMAPHORE macro to _GLIBCXX_USE_POSIX_SEMAPHORE for consistency with the similar _GLIBCXX_USE_CXX11_ABI macro that can be used to request an alternative (ABI-changing) implementation. libstdc++-v3/ChangeLog: PR libstdc++/100179 * include/bits/semaphore_base.h: Remove #error. * include/std/semaphore: Do not define anything unless one of the implementations is available. (cherry picked from commit 4b2db8077136d2f8b5a0db026e6161810be327b3)
