[Msys2-users] Qt under mysys2 w/ mingw64 - doesn't load QtCreator examples - can't seem to make c++17 work

[R A <da...@ya...>]

Hello,
I'm new in this list and somewhat new user, so I apologize if this is very noob issue to solve.
I've done basically everything I've could, including reinstalling *everything*, but can't seem to make the examples load in Qt. I suspect the issue might be the kit selected, but trying other custom kit also didn't work. All files seem to be properly installed in \msys64\mingw64\share\qt5\examples.
Second issue is that I'm unable to make c++17 get recognized, despite having GCC 8.2.0 and everything up to date. How do I properly pass the flag -std=c++17? Also, it would be nice if the code model recognized proper c++17 and clang. For instance, <filesystem> is there, but Qt says that std::filesystem::(smth) or std::copy_file are not in the namespace standard.
Any help is much appreciated.
ps: I'm using static Qt + mingw64.
cheers