I can confirm that these changes are required for the debug build to work on OSX (release build works anyway). Without them you get a load of linker errors. I am on Xcode 7.2.1 instead of Xcode 8 and I spent a couple of hours fixing it myself, then came here and saw this open pull request which is exactly the same as my commit. Sigh :)

I can explain the changes if you like;

gte.c - if that function isn't static then you get a linker error when compiling without optimizations in LLVM. See https://stackoverflow.com/questions/16740515/simple-c-inline-linker-error for example.

pgxp_gte.h - min() is undefined in pgxp_gte.c so linker error. I have absolutely no idea how the release build is picking it up, min()/max() are also defined in externals.h but that isn't included by pgxp_gte.c

project.pbxproj - pgxp_gpu.c is specific to the PeopsXgl target and cfg.c isn't used at all on OSX. Neither of them should be in the PCSXR target. I guess the release build just removes the unused code but this causes yet more linker errors in debug build.

PCSXR.xcscheme - this is just a minor project file format change done by Xcode 7 and later. It doesn't affect anything and it should be backward-compatible with Xcode 6 or whatever version the previous OSX maintainer was using.