The regex_constants::multiline constant is defined for non-strict C++11 and C++14 modes, on the basis that the feature is a DR (even though it was really a new feature addition to C++17 and probably shouldn't have gone through the issues list).
This makes the basic_regex::multiline constant defined consistently with the regex_constants::multiline one. For strict C++11 and C++14 mode we don't define them, because multiline is not a reserved name in those standards. libstdc++-v3/ChangeLog: * include/bits/regex.h (basic_regex::multiline): Define for non-strict C++11 and C++14 modes. * include/bits/regex_constants.h (regex_constants::multiline): Add _GLIBCXX_RESOLVE_LIB_DEFECTS comment. Tested x86_64-linux. Committed to trunk.
commit 17374dab3eefd282977ad90743c9aff97f2e41ce Author: Jonathan Wakely <jwak...@redhat.com> Date: Fri Oct 1 14:06:42 2021 libstdc++: Define basic_regex::multiline for non-strict modes The regex_constants::multiline constant is defined for non-strict C++11 and C++14 modes, on the basis that the feature is a DR (even though it was really a new feature addition to C++17 and probably shouldn't have gone through the issues list). This makes the basic_regex::multiline constant defined consistently with the regex_constants::multiline one. For strict C++11 and C++14 mode we don't define them, because multiline is not a reserved name in those standards. libstdc++-v3/ChangeLog: * include/bits/regex.h (basic_regex::multiline): Define for non-strict C++11 and C++14 modes. * include/bits/regex_constants.h (regex_constants::multiline): Add _GLIBCXX_RESOLVE_LIB_DEFECTS comment. diff --git a/libstdc++-v3/include/bits/regex.h b/libstdc++-v3/include/bits/regex.h index 664944b0ef2..ff908da3e94 100644 --- a/libstdc++-v3/include/bits/regex.h +++ b/libstdc++-v3/include/bits/regex.h @@ -424,7 +424,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 static constexpr flag_type awk = regex_constants::awk; static constexpr flag_type grep = regex_constants::grep; static constexpr flag_type egrep = regex_constants::egrep; -#if __cplusplus >= 201703L +#if __cplusplus >= 201703L || !defined __STRICT_ANSI__ static constexpr flag_type multiline = regex_constants::multiline; #endif ///@} diff --git a/libstdc++-v3/include/bits/regex_constants.h b/libstdc++-v3/include/bits/regex_constants.h index af689ff93af..0fd2879c817 100644 --- a/libstdc++-v3/include/bits/regex_constants.h +++ b/libstdc++-v3/include/bits/regex_constants.h @@ -171,6 +171,8 @@ namespace regex_constants static_cast<syntax_option_type>(1 << _S_egrep); #if __cplusplus >= 201703L || !defined __STRICT_ANSI__ + // _GLIBCXX_RESOLVE_LIB_DEFECTS + // 2503. multiline option should be added to syntax_option_type /** * Specifies that the `^` anchor matches at the beginning of a line, * and the `$` anchor matches at the end of a line, not only at the