[Bug objc/108743] -fconstant-cfstrings not supported

[ossman at cendio dot se via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108743

--- Comment #4 from Pierre Ossman <ossman at cendio dot se> ---
I am indeed trying to compile for macOS. Specifically Qt5, which is designed
with just Xcode in mind.