https://bugs.winehq.org/show_bug.cgi?id=50257
--- Comment #38 from Jacek Caban jacek@codeweavers.com --- (In reply to Alex S from comment #37)
That looks promising, however Clang can't find stdarg.h. I tried on the whim stdarg.h from FreeBSD, Glibc and Mingw-w64: Wine only sucessfully compiles with the header from Glibc. What's the deal with that?
stdarg.h is usually shipped with the compiler and Clang should provide one. Is it missing in your Clang installation (see eg. /usr/lib/clang/12.0.0/include/stdarg.h) for some reason?