8

我想在 C++17 中试用新的文件系统库，因此尝试从 cppreference.com 复制 std::filesystem::current_path 示例并使用来自 nuwen.net 的 MinGW 发行版的最新版本 (16.0) 对其进行编译我的 Windows 10 x64 机器。这包括 gcc v8.1，它应该根据cppreference.com 编译器支持页面支持文件系统库。

这是我要编译的代码：

#include <iostream>
#include <filesystem>
namespace fs = std::filesystem;
int main()
{
    std::cout << "Current path is " << fs::current_path() << '\n';
}

我正在使用的编译器命令：

g++ -std=c++17 filesystem_test.cpp

这是我在尝试编译时遇到的错误：

In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h: In member function 'std::filesystem::__cxx11::path& std::filesystem::__cxx11::path::operator/=(const std::filesystem::__cxx11::path&)':
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:47: error: no match for 'operator!=' (operand types are 'std::filesystem::__cxx11::path' and 'std::filesystem::__cxx11::path')
    || (__p.has_root_name() && __p.root_name() != root_name()))
                               ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
In file included from c:\mingw\include\c++\8.1.0\iosfwd:40,
                 from c:\mingw\include\c++\8.1.0\ios:38,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\postypes.h:221:5: note: candidate: 'template<class _StateT> bool std::operator!=(const std::fpos<_StateT>&, const std::fpos<_StateT>&)'
     operator!=(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\postypes.h:221:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::fpos<_StateT>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\stl_algobase.h:64,
                 from c:\mingw\include\c++\8.1.0\bits\char_traits.h:39,
                 from c:\mingw\include\c++\8.1.0\ios:40,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\stl_pair.h:456:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator!=(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)'
     operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\stl_pair.h:456:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::pair<_T1, _T2>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\stl_algobase.h:67,
                 from c:\mingw\include\c++\8.1.0\bits\char_traits.h:39,
                 from c:\mingw\include\c++\8.1.0\ios:40,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:311:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator!=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)'
     operator!=(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:311:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::reverse_iterator<_Iterator>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\stl_algobase.h:67,
                 from c:\mingw\include\c++\8.1.0\bits\char_traits.h:39,
                 from c:\mingw\include\c++\8.1.0\ios:40,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:349:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator!=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)'
     operator!=(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:349:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::reverse_iterator<_Iterator>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\stl_algobase.h:67,
                 from c:\mingw\include\c++\8.1.0\bits\char_traits.h:39,
                 from c:\mingw\include\c++\8.1.0\ios:40,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:1124:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator!=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)'
     operator!=(const move_iterator<_IteratorL>& __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:1124:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::move_iterator<_IteratorL>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\stl_algobase.h:67,
                 from c:\mingw\include\c++\8.1.0\bits\char_traits.h:39,
                 from c:\mingw\include\c++\8.1.0\ios:40,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:1130:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator!=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)'
     operator!=(const move_iterator<_Iterator>& __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\stl_iterator.h:1130:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::move_iterator<_IteratorL>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\string:41,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\allocator.h:158:5: note: candidate: 'template<class _T1, class _T2> bool std::operator!=(const std::allocator<_CharT>&, const std::allocator<_T2>&)'
     operator!=(const allocator<_T1>&, const allocator<_T2>&)
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\allocator.h:158:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::allocator<_CharT>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\string:41,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\allocator.h:164:5: note: candidate: 'template<class _Tp> bool std::operator!=(const std::allocator<_CharT>&, const std::allocator<_CharT>&)'
     operator!=(const allocator<_Tp>&, const allocator<_Tp>&)
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\allocator.h:164:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::allocator<_CharT>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\basic_string.h:48,
                 from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\string_view:454:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator!=(std::basic_string_view<_CharT, _Traits>, std::basic_string_view<_CharT, _Traits>)'
     operator!=(basic_string_view<_CharT, _Traits> __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\string_view:454:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'std::basic_string_view<_CharT, _Traits>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\basic_string.h:48,
                 from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\string_view:460:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator!=(std::basic_string_view<_CharT, _Traits>, std::__detail::__idt<std::basic_string_view<_CharT, _Traits> >)'
     operator!=(basic_string_view<_CharT, _Traits> __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\string_view:460:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'std::basic_string_view<_CharT, _Traits>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\bits\basic_string.h:48,
                 from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\string_view:466:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator!=(std::__detail::__idt<std::basic_string_view<_CharT, _Traits> >, std::basic_string_view<_CharT, _Traits>)'
     operator!=(__detail::__idt<basic_string_view<_CharT, _Traits>> __x,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\string_view:466:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'std::basic_string_view<_CharT, _Traits>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\basic_string.h:6056:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)'
     operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\basic_string.h:6056:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   'std::filesystem::__cxx11::path' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\basic_string.h:6069:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const _CharT*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)'
     operator!=(const _CharT* __lhs,
     ^~~~~~~~
c:\mingw\include\c++\8.1.0\bits\basic_string.h:6069:5: note:   template argument deduction/substitution failed:
In file included from c:\mingw\include\c++\8.1.0\filesystem:37,
                 from filesystem_test.cpp:2:
c:\mingw\include\c++\8.1.0\bits\fs_path.h:237:60: note:   mismatched types 'const _CharT*' and 'std::filesystem::__cxx11::path'
    || (__p.has_root_name() && __p.root_name() != root_name()))
                                                            ^
In file included from c:\mingw\include\c++\8.1.0\string:52,
                 from c:\mingw\include\c++\8.1.0\bits\locale_classes.h:40,
                 from c:\mingw\include\c++\8.1.0\bits\ios_base.h:41,
                 from c:\mingw\include\c++\8.1.0\ios:42,
                 from c:\mingw\include\c++\8.1.0\ostream:38,
                 from c:\mingw\include\c++\8.1.0\iostream:39,
                 from filesystem_test.cpp:1:
c:\mingw\include\c++\8.1.0\bits\basic_string.h:6081:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)'
     operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
<snip>

请注意，我必须剪掉错误消息的结尾以减少此问题的字符数。我已将整个错误消息放在这里：https ://pastebin.com/pnfMnMs7

编辑：根据 Galik 的评论，我尝试将编译器命令更改为

g++ -std=c++17 filesystem_test.cpp -lstdc++fs

但是我似乎得到与以前完全相同的错误

4

1 回答 1

4

尝试最新的msys2而不是 nuwen 发行版：

  1. 吃豆人-Syu

  2. pacman -S mingw-w64-x86_64-gcc

  3. gcc -v

    $ gcc -v 使用内置规范。COLLECT_GCC=C:\msys64\mingw64\bin\gcc.exe COLLECT_LTO_WRAPPER=C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/8.2.0/lto-wrapper.exe 目标：x86_64 -w64-mingw32 配置：../gcc-8.2.0/configure --prefix=/mingw64 --with-local-prefix=/mingw64/local --build=x86_64-w64-mingw32 --host=x86_64- w64-mingw32 --target=x86_64-w64-mingw32 --with-native-system-header-dir=/mingw64/x86_64-w64-mingw32/include --libexecdir=/mingw64/lib --enable-bootstrap --with -arch=x86-64 --with-tune=generic --enable-languages=ada,c,lto,c++,objc,obj-c++,https://sourceforge.net/projects/msys2 --with-gnu-as --with-gnu-ld 线程模型：posix gcc 8.2.0 版（Rev1，由 MSYS2 项目构建）

于 2018-09-17T23:27:50.253 回答