[RFC] Tightening up the type system

[Geoffrey Keating]

Diego Novillo <dnovillo@redhat.com> writes:

> In fact, I would like to get to the point where we can simply call
> 'gcc_assert (lang_hook.compatible_types_p (dest, orig))' when doing
> propagation.  Ideally, all the necessary type conversions should be
> exposed in the IL.

Should the validity of GIMPLE really depend on a language hook like
this?  Surely it would make more sense to have a
gimple_compatible_types_p that reflects what code that parses GIMPLE
can actually handle (presumably a superset of what each language can
generate).