[PATCH] Make alias_sets_conflict_p less conservative

[Richard Kenner]

> So I'm still inclined to go with my patch with adding a big'n'fat
> comment.

I think your patch is wrong: it says that two alias set don't conflict
when, in fact, they do.

Bugs caused by this are notoriously hard to find because they come and go
so I'd be very much against introducing this into GCC even if the only
bug is a latent one.