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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/108385] [12 Regression] false positive
 -Wfree-nonheap-object
Date: Fri, 13 Jan 2023 09:26:56 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108385

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #5)
> [E]VRP testcase which shows the odd 'off' range on the false edge:
>=20
> void bar(char *);
>=20
> void foo (char *p, char *pp, int off)
> {
>   char *q =3D p + off;
>   if (q !=3D p)
>     bar (q);
>   char *qq =3D pp + off;
>   if (qq !=3D pp)
>     bar (qq);
>   bar (p);
>   bar (pp);
> }

In the old VRP code the register_edge_assert_for_* routines would be
the ones to add pattern matching for this.  I can't find where such
code exists in ranger now - I suspected it might be in range-op
when solving q =3D p + off; with q =3D=3D p, but that operates on ranges
and not equivalences only?=