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Re: [PATCH] Make alias_sets_conflict_p less conservative
On Tue, 4 Mar 2008, Richard Kenner wrote:
> > This is because the the type based rules (at least for C) say "access
> > through pointer char can validly alias anything" but not "access
> > through pointer to anything can validly alias char".
>
> I note there is no char * in sight there. Are we, by some chance, assigning
> char to alias set zero? That seems wrong. Rather char * should be
> marked as type-pointed-to-can-alias-all.
Yes, char is assigned alias set zero. And this is correct.
char a[4];
int *p;
an access through *p conflicts with a. (note there is no char * involved
here)
Richard.