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Re: Lowering of types?
Richard Guenther <richard.guenther@gmail.com> writes:
> On 6/2/05, Richard Henderson <rth@redhat.com> wrote:
> > On Thu, Jun 02, 2005 at 11:21:31AM +0200, Richard Guenther wrote:
> > > During type checking of the middle-end in the tree-optimizers
> > > we run into type mismatches like
> >
> > This isn't a type mismatch if the compatible_p langhook says
> > they aren't. Which I expect is true.
>
> What exactly does it mean to the middle-end, if the compatible_p
> langhook says true? Does it mean if the middle-end exchanges one
> type for the other there should be no observable effects (correctness
> wise) down the road?
If the middle-end exchanges values of one type for the other there
should be no problems. Swapping the actual types could cause
problems, for instance if you replace a complete structure with an
incomplete version.