Re: [PATCH] Repair TYPE_REF_CAN_ALIAS_ALL machinery (take 2)

["Richard Guenther" <richard dot guenther at gmail dot com>]

On 5/24/06, Eric Botcazou <ebotcazou@adacore.com> wrote:
> > It looks like this will not work for
> >
> >  int *i;
> >  float *f (can alias all);
> >  *i = 1;
> >  *f = 2;
> >  return *i;
> >
> > because aliasing will have
> >
> >  # VDEF<SMT.int>
> >  *i = 1;
> >  # VDEF<SMT.can_alias_all>
> >  *f = 2;
> >  # VUSE<SMT.int>
> >  return *i;
> >
> > And we happily propagate the 1 to the return statement.  no?  I.e. the
> > can_alias_all will only alias theirself, not everything.
> >
> > Or am I missing something?
>
> The assignment between f and i somewhere?
>
>   f = (float *)i;

It was just illustration ;)  Make it two incoming parameters to a
function, the assignment
being in the caller.  At least it looks fragile to me.

Richard.