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Re: must_alias question


> On Thu, 2003-11-20 at 15:31, Jan Hubicka wrote:
> 
> > char global;
> > t()
> > {
> >   char *a=global;
> >   char **b=&a;
> >   return *a;
> > }
> > must_alias clears may_point_to_global_mem for variable a based on fact
> > that it's address is no longer taken.  This looks just wrong.
> > the fact that we don't take address of pointer has nothing to do about
> > the fact whehtehr it points to global memory or not.
> > Or am I missunderstanding semantics of the flag?
> > 
> Nope, that sounds right.  Clearing the flag doesn't seem correct. 
> Thanks for noticing.
The bug is probably reason for the FIXME disabling the function for
pointer types BTW :)
I see your tree-sra code is in.  Once I figure out why it breaks my
bootstrap (clean SSA tree now again dies in libstdc++ build in different
way for me), I will test all the changes I cumulated for mustalias pass.
I think we can kill ADDRESSOF beast now that will make things a lot
easier.

Honza
> 
> 
> Diego.


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