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Re: [PATCH] Fix optimization regression in constant folder

Hi,

On Wed, 3 Oct 2007, Eric Botcazou wrote:

> > > OK, so TYPE_IGNORE_OVERFLOWS + TYPE_OVERFLOW_WRAPS for sizetypes?
> >
> > That makes sense to me.
> 
> Agreed.
> 
> Next question: independently of the underlying type of not?

If you determined, that yes you indeed want that behaviour of your type X, 
then yes, independend of the other properties like signedness (of course 
if the combination makes sense, which it does here).

> For all languages minus Ada sizetypes are unsigned so 
> TYPE_IGNORE_OVERFLOWS+TYPE_OVERFLOW_WRAPS is kind of natural.  For Ada, 
> sizetypes are signed (Richard explained why) so 
> TYPE_IGNORE_OVERFLOWS+TYPE_OVERFLOW_WRAPS is not natural.

That shouldn't bother us.  It might of course be that we have some 
transformations which explicitely look for unsignedness, whereas you also 
want them to apply to your sizetypes.  We simply have to find and fix 
them.


Ciao,
Michael.
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