https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117912
--- Comment #17 from Siddhesh Poyarekar <siddhesh at gcc dot gnu.org> ---
(In reply to Siddhesh Poyarekar from comment #16)
> (In reply to Andrew Pinski from comment #15)
> > (In reply to Jakub Jelinek from comment #14)
> > > struct S { int a; int b[24]; int c[24]; int d; };
> > > void bar (int *);
> > >
> > > __SIZE_TYPE__
> > > foo (struct S *p)
> > > {
> > > bar (&p->b[24]);
> > > bar (&p->c[0]);
> > > return __builtin_object_size (&p->c[0], 1);
> > > }
>
> Couldn't VN/CSE, when eliminating an expression involving pointers to
> component_refs, pick the one that points to the beginning of a component
> rather than the end? That should solve both these problems.
Sorry, hit submit before finishing my thought. There's a chance that it could
miss actual sub-object overwrites to, e.g. &p->b[24] but hopefully early_objsz
will catch that and pass it on to objsz.
