efa64fcce1
Because of LWG 467, std::char_traits<char>::lt compares the values cast to unsigned char rather than char, so even when char is signed we get unsigned comparision. std::char_traits<char>::compare uses __builtin_memcmp and that works the same, but during constexpr evaluation we were calling __gnu_cxx::char_traits<char_type>::compare. As char_traits::lt is not virtual, __gnu_cxx::char_traits<char_type>::compare used __gnu_cxx::char_traits<char_type>::lt rather than std::char_traits<char>::lt and thus compared chars as signed if char is signed. This change fixes it by inlining __gnu_cxx::char_traits<char_type>::compare into std::char_traits<char>::compare by hand, so that it calls the right lt method. 2021-02-23 Jakub Jelinek <jakub@redhat.com> PR libstdc++/99181 * include/bits/char_traits.h (char_traits<char>::compare): For constexpr evaluation don't call __gnu_cxx::char_traits<char_type>::compare but do the comparison loop directly. * testsuite/21_strings/char_traits/requirements/char/99181.cc: New test. |
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| .. | ||
| 17_intro | ||
| 18_support | ||
| 19_diagnostics | ||
| 20_util | ||
| 21_strings | ||
| 22_locale | ||
| 23_containers | ||
| 24_iterators | ||
| 25_algorithms | ||
| 26_numerics | ||
| 27_io | ||
| 28_regex | ||
| 29_atomics | ||
| 30_threads | ||
| abi | ||
| backward | ||
| config | ||
| data | ||
| decimal | ||
| experimental | ||
| ext | ||
| lib | ||
| libstdc++-abi | ||
| libstdc++-dg | ||
| libstdc++-prettyprinters | ||
| libstdc++-xmethods | ||
| performance | ||
| special_functions | ||
| std | ||
| tr1 | ||
| tr2 | ||
| util | ||
| Makefile.am | ||
| Makefile.in | ||