I was able to compile and install.
However, I cannot launch emacs outside of mingw64.
I installed emacs-nativecomp outside of mingw64 in order not to mess with the mingw emacs package.
I copied libgmp*dll in the installdir/bin and added the absolute path of "/mingw64/bin" to the emacs exec-path.
Outside of mingw64, If I just click on bin/emacs.exe I get a console message :
Warning: arch-dependent data dir '%emacs_dir%/libexec/emacs/28.0.50/x86_64-w64-mingw32/': No such file or directory
and an emacs abort dialog.
If I launch emacs on the command line from within a mingw64 shell, it runs well. But it is not desirable because window
environment variables like %VAR% are not expanded correctly.
I can launch the mingw64 emacs package from outside mingw without this problem.
So, most probably, I must have missed something during the install.
Do you also have this issue ?
Regards