Compile error under MinGW (Windows)

[mjh65]

Commit f9128d1 introduces a compilation error when building with MinGW for Windows.

W:/avitab/src/avitab/apps/MapApp.cpp: In member function 'void avitab::MapApp::selectOnlineMaps()':
W:/avitab/src/avitab/apps/MapApp.cpp:312:42: error: no matching function for call to 'std::vector<std::__cxx11::basic_string >::vector()'
312 | fs::u8path(mapConfigPath)});
| ^
In file included from C:/msys64/mingw64/include/c++/12.1.0/vector:64,
from W:/avitab/src/avitab/apps/MapApp.h:23,
from W:/avitab/src/avitab/apps/MapApp.cpp:21:
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:551:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(size_type, const allocator_type&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; size_type = long long unsigned int; allocator_type = std::allocator<std::__cxx11::basic_string >]'
551 | vector(size_type __n, const allocator_type& __a = allocator_type())
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:551:51: note: no known conversion for argument 2 from 'std::filesystem::__cxx11::path' to 'const std::vector<std::__cxx11::basic_string >::allocator_type&' {aka 'const std::allocator<std::__cxx11::basic_string >&'}
551 | vector(size_type __n, const allocator_type& __a = allocator_type())
| ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:564:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(size_type, const value_type&, const allocator_type&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; size_type = long long unsigned int; value_type = std::__cxx11::basic_string; allocator_type = std::allocator<std::__cxx11::basic_string >]'
564 | vector(size_type __n, const value_type& __value,
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:564:47: note: no known conversion for argument 2 from 'std::filesystem::__cxx11::path' to 'const std::vector<std::__cxx11::basic_string >::value_type&' {aka 'const std::__cxx11::basic_string&'}
564 | vector(size_type __n, const value_type& __value,
| ~~~~~~~~~~~~~~~~~~^~~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:702:9: note: candidate: 'template<class _InputIterator, class> std::vector<_Tp, _Alloc>::vector(_InputIterator, _InputIterator, const allocator_type&) [with = _InputIterator; _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >]'
702 | vector(_InputIterator __first, _InputIterator __last,
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:702:9: note: template argument deduction/substitution failed:
W:/avitab/src/avitab/apps/MapApp.cpp:312:42: note: deduced conflicting types for parameter '_InputIterator' ('const char*' and 'std::filesystem::__cxx11::path')
312 | fs::u8path(mapConfigPath)});
| ^
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:673:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::initializer_list<_Tp>, const allocator_type&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; allocator_type = std::allocator<std::__cxx11::basic_string >]'
673 | vector(initializer_list<value_type> __l,
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:673:43: note: no known conversion for argument 1 from 'const char [38]' to 'std::initializer_list<std::__cxx11::basic_string >'
673 | vector(initializer_list<value_type> __l,
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:654:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, std::__type_identity_t<_Alloc>&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; std::__type_identity_t<_Alloc> = std::allocator<std::__cxx11::basic_string >]'
654 | vector(vector&& __rv, const __type_identity_t<allocator_type>& __m)
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:654:23: note: no known conversion for argument 1 from 'const char [38]' to 'std::vector<std::__cxx11::basic_string >&&'
654 | vector(vector&& __rv, const __type_identity_t<allocator_type>& __m)
| ~~~~~~~~~^~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:635:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, const allocator_type&, std::false_type) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; allocator_type = std::allocator<std::__cxx11::basic_string >; std::false_type = std::integral_constant<bool, false>]'
635 | vector(vector&& __rv, const allocator_type& __m, false_type)
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:635:7: note: candidate expects 3 arguments, 2 provided
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:630:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&, const allocator_type&, std::true_type) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; allocator_type = std::allocator<std::__cxx11::basic_string >; std::true_type = std::integral_constant<bool, true>]'
630 | vector(vector&& __rv, const allocator_type& __m, true_type) noexcept
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:630:7: note: candidate expects 3 arguments, 2 provided
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:619:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const std::vector<_Tp, _Alloc>&, std::__type_identity_t<_Alloc>&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; std::__type_identity_t<_Alloc> = std::allocator<std::__cxx11::basic_string >]'
619 | vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:619:28: note: no known conversion for argument 1 from 'const char [38]' to 'const std::vector<std::__cxx11::basic_string >&'
619 | vector(const vector& __x, const __type_identity_t<allocator_type>& __a)
| ~~~~~~~~~~~~~~^~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:615:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(std::vector<_Tp, _Alloc>&&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >]'
615 | vector(vector&&) noexcept = default;
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:615:7: note: candidate expects 1 argument, 2 provided
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:596:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const std::vector<_Tp, _Alloc>&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >]'
596 | vector(const vector& __x)
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:596:7: note: candidate expects 1 argument, 2 provided
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:537:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector(const allocator_type&) [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >; allocator_type = std::allocator<std::__cxx11::basic_string >]'
537 | vector(const allocator_type& __a) _GLIBCXX_NOEXCEPT
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:537:7: note: candidate expects 1 argument, 2 provided
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:526:7: note: candidate: 'std::vector<_Tp, _Alloc>::vector() [with _Tp = std::__cxx11::basic_string; _Alloc = std::allocator<std::__cxx11::basic_string >]'
526 | vector() = default;
| ^~~~~~
C:/msys64/mingw64/include/c++/12.1.0/bits/stl_vector.h:526:7: note: candidate expects 0 arguments, 2 provided
make[2]: *** [CMakeFiles/avitab_common.dir/build.make:1322: CMakeFiles/avitab_common.dir/src/avitab/apps/MapApp.cpp.obj] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: Leaving directory '/w/avitab/build'
make[1]: *** [CMakeFiles/Makefile2:128: CMakeFiles/avitab_common.dir/all] Error 2
make[1]: Leaving directory '/w/avitab/build'
make: *** [Makefile:136: all] Error 2
make: Leaving directory '/w/avitab/build'

[mjh65]

I think this is because fs::u8path() on Windows returns a basic_string<wchar_t> (and there is no implicit conversion to std::string available.) Not yet certain whether an easy (portable) fix is available, or if some conditional code will be required for WIndows.

[mjh65]

OK, fix looks fairly easy: fs::u8path(mapConfigPath).string()});

I think that should be portable too?