From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id DB6CA3858C50; Mon, 16 May 2022 10:42:56 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DB6CA3858C50 From: "christian.morales.vega at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/105616] New: Using regex_replace throws "maybe-uninitialized" warnings Date: Mon, 16 May 2022 10:42:56 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libstdc++ X-Bugzilla-Version: 12.1.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: christian.morales.vega at gmail dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 May 2022 10:42:57 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105616 Bug ID: 105616 Summary: Using regex_replace throws "maybe-uninitialized" warnings Product: gcc Version: 12.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: christian.morales.vega at gmail dot com Target Milestone: --- As can be seen in https://godbolt.org/z/qK976bqzf Building -------------------- #include #include #include #include int main() { std::string text =3D "Quick brown fox"; std::regex vowel_re("a|e|i|o|u"); // write the results to an output iterator std::regex_replace(std::ostreambuf_iterator(std::cout), text.begin(), text.end(), vowel_re, "*"); // construct a string holding the results std::cout << '\n' << std::regex_replace(text, vowel_re, "[$&]") << '\n'; } -------------------- (taken from https://en.cppreference.com/w/cpp/regex/regex_replace) with "-fsanitize=3Daddress -O1 -Wmaybe-uninitialized" creates a long list of warnings -------------------- In file included from /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/regex:48, from :3: In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_end() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :290:24: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ In file included from /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/regex:63: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_end() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :287:17: note: '__tmp' declared here 287 | _StateT __tmp(_S_opcode_subexpr_end); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_end() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :290:24: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_end() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :287:17: note: '__tmp' declared here 287 | _StateT __tmp(_S_opcode_subexpr_end); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_begin() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :281:24: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_begin() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :279:17: note: '__tmp' declared here 279 | _StateT __tmp(_S_opcode_subexpr_begin); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_begin() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :281:24: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_subexpr_begin() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :279:17: note: '__tmp' declared here 279 | _StateT __tmp(_S_opcode_subexpr_begin); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_backref(std::size_t) [with _Traits= T =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc:173:29: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ In file included from /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :400: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc: In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_backref(std::size_t) [with _Traits= T =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc:171:15: note: '__tmp' declared here 171 | _StateT __tmp(_S_opcode_backref); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_backref(std::size_t) [with _Traits= T =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc:173:29: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc: In member function 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_backref(std::size_t) [with _Traits= T =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.t= cc:171:15: note: '__tmp' declared here 171 | _StateT __tmp(_S_opcode_backref); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:189:15: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:189:15: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:199:17: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:199:17: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:208:15: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:208:15: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:246:19: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:246:19: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:264:42: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_repeat(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :263:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:264:42: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_quantifier() [= with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :257:17: note: '__tmp' declared here 257 | _StateT __tmp(_S_opcode_repeat); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_alt(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :251:24, inlined from 'void std::__detail::_Compiler<_TraitsT>::_M_disjunction() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:103:18: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'void std::__detail::_Compiler<_TraitsT>::_M_disjunction() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :246:17: note: '__tmp' declared here 246 | _StateT __tmp(_S_opcode_alternative); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_alt(std::__detail::_StateIdT, std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :251:24, inlined from 'void std::__detail::_Compiler<_TraitsT>::_M_disjunction() [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:103:18: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'void std::__detail::_Compiler<_TraitsT>::_M_disjunction() [with _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :246:17: note: '__tmp' declared here 246 | _StateT __tmp(_S_opcode_alternative); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_word_bound(bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :309:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [= with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:153:16: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [w= ith _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :307:17: note: '__tmp' declared here 307 | _StateT __tmp(_S_opcode_word_boundary); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_word_bound(bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :309:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [= with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:153:16: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [w= ith _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :307:17: note: '__tmp' declared here 307 | _StateT __tmp(_S_opcode_word_boundary); | ^~~~~ In constructor 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]', inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_lookahead(std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :318:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [= with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:164:8: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 5:42: warning: '*(std::function*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::function::_M_invoker' may be used uninitialized [-Wmaybe-uninitialized] 405 | : _Function_base(), _M_invoker(__x._M_invoker) | ~~~~^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [w= ith _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :315:17: note: '__tmp' declared here 315 | _StateT __tmp(_S_opcode_subexpr_lookahead); | ^~~~~ In member function 'bool std::_Function_base::_M_empty() const', inlined from 'std::function<_Res(_ArgTypes ...)>::operator bool() const [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:57= 4:25, inlined from 'std::function<_Res(_ArgTypes ...)>::function(std::function<_Res(_ArgTypes ...)>&&) [with _Res =3D bool; _ArgTypes =3D {char}]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:40= 7:6, inlined from 'std::__detail::_State<_Char_type>::_State(std::__detail::_State<_Char_type= >&&) [with _Char_type =3D char]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :149:4, inlined from 'std::__detail::_StateIdT std::__detail::_NFA<_TraitsT>::_M_insert_lookahead(std::__detail::_StateIdT, bool) [with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :318:24, inlined from 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [= with _TraitsT =3D std::__cxx11::regex_traits]' at /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_compiler.tc= c:164:8: /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/std_function.h:24= 7:37: warning: '*(const std::_Function_base*)((char*)&__tmp + offsetof(std::__detail::_StateT, std::__detail::_State::.std::__detail::_State_base::)).std::_Function_base::_M_manager' may be used uninitialized [-Wmaybe-uninitialized] 247 | bool _M_empty() const { return !_M_manager; } | ^~~~~~~~~~ /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= : In member function 'bool std::__detail::_Compiler<_TraitsT>::_M_assertion() [w= ith _TraitsT =3D std::__cxx11::regex_traits]': /opt/compiler-explorer/gcc-12.1.0/include/c++/12.1.0/bits/regex_automaton.h= :315:17: note: '__tmp' declared here 315 | _StateT __tmp(_S_opcode_subexpr_lookahead); | ^~~~~ -------------------- The same problem happens with Fedora 36 / gcc 12.1.1 and doesn't happen with 11.3. Not sure if it's a problem with g++, ASAN or libstdc++.=