https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107376
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:988dd22ec6665117e8587389ac85389f1c321c45 commit r13-3548-g988dd22ec6665117e8587389ac85389f1c321c45 Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Oct 25 13:03:12 2022 +0100 libstdc++: Fix allocator propagation in regex algorithms [PR107376] The PR points out that we assume the match_results allocator is default constuctible, which might not be true. We also have a related issue with unwanted propagation from an object that might have an unequal allocator. Ideally we use the same allocator type for _State_info::_M_match_queue but that would be an ABI change now. We should investigate if that can be done without breaking anything, which might be possible because the _Executor object is short-lived and never leaks out of the regex_match, regex_search, and regex_replace algorithms. If we change the mangled name for _Executor then there would be no ODR violations when mixing old and new definitions. This commit does not attempt that. libstdc++-v3/ChangeLog: PR libstdc++/107376 * include/bits/regex_executor.h (_Executor::_Executor): Use same allocator for _M_cur_results and _M_results. * include/bits/regex_executor.tcc (_Executor::_M_main_dispatch): Prevent possibly incorrect allocator propagating to _M_cur_results. * testsuite/28_regex/algorithms/regex_match/107376.cc: New test.