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Re: Aliasing violation generated by fold_builtin_memcmp?
On Fri, 2005-09-30 at 15:54 +0200, Olivier Hainque wrote:
> Daniel Berlin wrote:
> > > Out of a preliminary look into this code (new to me), a possible
> > > place to address that appears to be 'get_tmt_for', which
> > > presumably should assign a zero alias set to tags for pointer
> > > types with that bit set.
>
> > Actually, you just want it to assign the same tag, not change the alias
> > set of every tag it assigns.
>
> Humm, and still have the corresponding alias set zero to ensure it conflicts
> with everything, right ?
Yes. :)
>
> In which case almost all the bits are in already, since get_tmt_for
> already reuses a previously created tag if it assigned the same alias set.
>
> I tried this on a couple of testcases yesterday, and it worked fine.
>
> I am still unclear on one point: is it fine to reuse the same tag for
> possibly different designated types ?
Yes, as long as they have the same alias set.
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