Thanks. CCore.h is what I expect.
And I'll try to see why your CK_OPTIONS is working on Linux while my OF_OPTIONS is not. OF_OPTIONS fail to compile on Linux · Issue #2 · Kyle-Ye/OpenSwiftUI · GitHub
Update:
Looks like your usage is within a systemTarget while mine is a target. And the workaround I found is set -Wno-elaborated-enum-base.