https://bugs.winehq.org/show_bug.cgi?id=50790
--- Comment #2 from Gcenx gcenx83@gmail.com --- In this case I’m building on Mojave and running the resulting build in the 10.9 VM.
If I were to build modern wine on 10.9 I’d use a newer version of clang and the 10.10 or greater SDK over modifying wine sources.
Though a patch set with your edits for building on 10.9 using its SDK would be something nice I could add to my Macports overlays.