From 9a2451c1013c21e76da89df89c3c8e5e6afe6154 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Fri, 17 Dec 2021 17:58:09 +0000 Subject: [PATCH] libstdc++: Compare match_results for failed regex_match The regex_match_debug testsuite helper doesn't compare the std::match_results objects after a failed match, but it should do. The standard says that the effects of a failed match on the match-results are unspecified, except that [conditions testable by operator==]. So we can check that the two sets of results compare equal even if the match failed. libstdc++-v3/ChangeLog: * testsuite/util/testsuite_regex.h (regex_match_debug): Compare results even if the match failed. --- libstdc++-v3/testsuite/util/testsuite_regex.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/libstdc++-v3/testsuite/util/testsuite_regex.h b/libstdc++-v3/testsuite/util/testsuite_regex.h index 6af3d8d836f..f2bb068024d 100644 --- a/libstdc++-v3/testsuite/util/testsuite_regex.h +++ b/libstdc++-v3/testsuite/util/testsuite_regex.h @@ -150,8 +150,7 @@ namespace __gnu_test auto __res2 = __regex_algo_impl<_Bi_iter, _Alloc, _Ch_type, _Rx_traits, _RegexExecutorPolicy::_S_alternate, true> (__s, __e, __mm, __re, __flags); - // __m is unspecified if return value is false. - if (__res1 == __res2 && (!__res1 || __m == __mm)) + if (__res1 == __res2 && __m == __mm) return __res1; throw std::exception(); }