https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88662
Jonathan Wakely <redi at gcc dot gnu.org> changed:
What |Removed |Added
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Keywords| |documentation
--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to gnzlbg from comment #0)
> Compiling
>
> unsigned int foo(unsigned int x, _Bool b) {
> return x - (unsigned int)b;
> }
>
> only produces correct results if the value of `_Bool` is either `0` or `1`
Because (unsigned int)b is undefined otherwise.
> [0], see https://gcc.godbolt.org/z/l0DPjc:
>
> foo:
> movzx esi, sil
> mov eax, edi
> sub eax, esi
> ret
>
> This probably means that all other representations of `_Bool` are trap
> representations, but this does not appear to be documented anywhere.
The representation of _Bool is unspecified, not implementation-defined, so
doesn't need to be documented.
