https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64913
Bug ID: 64913 Summary: basic_string fails to use custom allocator Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: antoshkka at gmail dot com Consider the following example: template<class CharT> struct my_allocator : std::allocator<CharT> {}; typedef std::basic_string< char , std::char_traits<char> , my_allocator<char> > my_string; my_string s1; my_string s2(static_cast<my_string&&>(s1)); // Oops Attempt to move construct my_string produces the following error: /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h: In instantiation of ???std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::basic_string(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = my_allocator<char>]???: ../boost/lexical_cast.hpp:45:16: required from ???Target boost::lexical_cast(const Source&) [with Target = std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >; Source = std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >]??? ../libs/lexical_cast/test/lexical_cast_test.cpp:510:5: required from here /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:475:73: error: no matching function for call to ???std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::pointer, std::remove_reference<std::allocator<char>&>::type)??? : _M_dataplus(_M_local_data(), std::move(__str._M_get_allocator())) ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:108:2: note: candidate: std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::pointer, const _Alloc&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = my_allocator<char>; std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::pointer = char*] _Alloc_hider(pointer __dat, const _Alloc& __a = _Alloc()) ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:108:2: note: no known conversion for argument 2 from ???std::remove_reference<std::allocator<char>&>::type {aka std::allocator<char>}??? to ???const my_allocator<char>&??? /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate: std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::_Alloc_hider::_Alloc_hider(const std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::_Alloc_hider&) struct _Alloc_hider : allocator_type // TODO check __is_final ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate expects 1 argument, 2 provided /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate: std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<char, std::char_traits<char>, my_allocator<char> >::_Alloc_hider&&) /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate expects 1 argument, 2 provided /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h: In instantiation of ???std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::basic_string(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&&) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; _Alloc = my_allocator<wchar_t>]???: ../boost/lexical_cast.hpp:45:16: required from ???Target boost::lexical_cast(const Source&) [with Target = std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >; Source = std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >]??? ../libs/lexical_cast/test/lexical_cast_test.cpp:532:5: required from here /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:475:73: error: no matching function for call to ???std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::pointer, std::remove_reference<std::allocator<wchar_t>&>::type)??? : _M_dataplus(_M_local_data(), std::move(__str._M_get_allocator())) ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:108:2: note: candidate: std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::pointer, const _Alloc&) [with _CharT = wchar_t; _Traits = std::char_traits<wchar_t>; _Alloc = my_allocator<wchar_t>; std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::pointer = wchar_t*] _Alloc_hider(pointer __dat, const _Alloc& __a = _Alloc()) ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:108:2: note: no known conversion for argument 2 from ???std::remove_reference<std::allocator<wchar_t>&>::type {aka std::allocator<wchar_t>}??? to ???const my_allocator<wchar_t>&??? /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate: std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::_Alloc_hider::_Alloc_hider(const std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::_Alloc_hider&) struct _Alloc_hider : allocator_type // TODO check __is_final ^ /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate expects 1 argument, 2 provided /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate: std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::_Alloc_hider::_Alloc_hider(std::__cxx11::basic_string<wchar_t, std::char_traits<wchar_t>, my_allocator<wchar_t> >::_Alloc_hider&&) /home/trippels/gcc_test/usr/local/include/c++/5.0.0/bits/basic_string.h:106:14: note: candidate expects 1 argument, 2 provided