[Bug middle-end/66110] uint8_t memory access not optimized

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66110

--- Comment #17 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Pedro Alves from comment #16)
> I ran into this, and thought that:
> 
>  typedef unsigned int __attribute__ ((__mode__(__byte__))) byte;
> 
> or:
> 
>  typedef unsigned int __attribute__ ((__mode__(QI))) byte;
> 
> might be syntax that already worked for creating an 8-bit type that doesn't
> alias.  Alas, it does not work.  Maybe it should.

The reason it does not work is that we handle it by querying the frontend
for a type corresponding to that mode so it returns unsigned char.