[RFC] ignoring type alias conflicts between structures and scalars

[Richard Kenner]

    your example is different, in that the int lvalue is not some arbitrary
    pointer dereference, but a known variable.

Yes, I think that's the key.  The alias_sets_conflict_p routine was meant
originally for an RTL environment where every MEM was potentially a pointer
dereference (yes, we knew some of those that weren't, but didn't do much with
that knowlege).  If you want to distinguish between pointers to a type and
variables of that type, you don't have to do the symmetric test.