Quantization compatible Xcode 9 for 16-bit, not for 8-bit and under

[alexiscreuzot]

For some reason when I try quantizing existing models I have, I manage to get 16-bit models working on Xcode 9.4.1, but not 8-bit or less.

When I go under 16-bit, Xcode shows me this error :

Is it because Xcode 9 inherently doesn't support 8-bit fixed point representation ?