Does Qt 5.15.1 MingW8.1.0 support c++17?

Bruce.Zhang

$ mingw32-make.exe
Scanning dependencies of target gpds-static
[  0%] Building CXX object _deps/gpds-build/lib/CMakeFiles/gpds-static.dir/src/archiver_xml.cpp.obj
In file included from C:/Qt/Tools/mingw810_32/lib/gcc/i686-w64-mingw32/8.1.0/include/c++/filesystem:37,
                 from C:/Projects/Vision/QSchematic/build/_deps/gpds-src/lib/include/gpds/archiver.hpp:3,
                 from C:/Projects/Vision/QSchematic/build/_deps/gpds-src/lib/include/gpds/archiver_xml.hpp:4,
                 from C:\Projects\Vision\QSchematic\build\_deps\gpds-src\lib\src\archiver_xml.cpp:2:
C:/Qt/Tools/mingw810_32/lib/gcc/i686-w64-mingw32/8.1.0/include/c++/bits/fs_path.h: In member function 'std::filesystem::__cxx11::path& std::filesystem::__cxx11::path::operator/=(const std::filesystem::__cxx11::path&)':
C:/Qt/Tools/mingw810_32/lib/gcc/i686-w64-mingw32/8.1.0/include/c++/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()))
                               ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~

ChrisW67

GCC 8.1.0 should with some gaps. C++17 support was experimental until GCC 9.1.

The namespace std::filesystem::__cxx11::path and the error looks suspiciously like the source is not being processed as C++17.
What is in your PRO file/CMakeLists.txt to enable C++17?

Bruce.Zhang

@ChrisW67
I set the C++17 flag as bellow:

set(CMAKE_CXX_STANDARD 17)

If I compile with vs2017 works fine.

jsulm

@Bruce-Zhang Did you enable C++17 in your pro file?

CONFIG += c++17