Can't compile libretro dll on Windows

[raidenii]

Tried to use MSYS2 with Mingw64 on Windows 10.

If using mingw64 to compile, it will fail with the following:

me@My-Desktop MINGW64 /r/freej2me/src/libretro
$ make
gcc -Wall -D__LIBRETRO__ -Ideps/libretro-common/include   -c -o freej2me_libretro.o freej2me_libretro.c
freej2me_libretro.c:24:10: fatal error: sys/wait.h: No such file or directory
   24 | #include <sys/wait.h>
      |          ^~~~~~~~~~~~
compilation terminated.
make: *** [Makefile:133：freej2me_libretro.o] Error 1

me@My-Desktop MINGW64 /r/freej2me/src/libretro
$

My understanding is that sys/wait.h is for POSIX which is not supported on Windows, thus compilation failure.

If using MSYS2 without mingw64, it compiles, but fails to load in RetroArch.