https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93972
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:ce33801fe4c2272b31c64288b34c67a61529ce37 commit r10-6930-gce33801fe4c2272b31c64288b34c67a61529ce37 Author: Patrick Palka <ppa...@redhat.com> Date: Fri Feb 28 14:16:06 2020 -0500 libstdc++: Fix bogus use of memcmp in ranges::lexicographical_compare (PR 93972) We were enabling the memcmp optimization in ranges::lexicographical_compare for signed integral types and for integral types wider than a byte. But memcmp gives the wrong answer for arrays of such types. This patch fixes this issue by refining the condition that enables the memcmp optimization. It's now consistent with the corresponding condition used in std::lexicographical_compare. libstdc++-v3/ChangeLog: PR libstdc++/93972 * include/bits/ranges_algo.h (__lexicographical_compare_fn::operator()): Fix condition for when to use memcmp, making it consistent with the corresponding condition used in std::lexicographical_compare. * testsuite/25_algorithms/lexicographical_compare/93972.cc: New test.
