[Bug c/116193] enhancement: type attribute that causes overflow for unsigned integer types to trap

[foss+gcc@alejandro-colomar.es]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116193

Alejandro Colomar <foss+gcc@alejandro-colomar.es> changed:

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--- Comment #6 from Alejandro Colomar <foss+gcc@alejandro-colomar.es> ---
+1

I was just once again bitten by unsigned arithmetic.  In this case, I had to
use id_t, because I'm handling uids and gids.  I would be happy if
id_t,uid_t,gid_t were all signed integers, but that's not up to me to decide.

If I could at least mark them as non-wrapping integers, I'd be safe from these
bugs.

Since most unsigned integers are used where wrap-around is not intended, I
think it would be good to have something like -funsigned-overflow-traps and
then have an attribute to mark the few unsigned types where we do actually want
to wrap around.