From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 0B1B33858426; Fri, 12 May 2023 07:00:46 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0B1B33858426
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1683874847;
	bh=8rHUUSjSppdgwoK9q8s8eFiFdd/cnZ1Pdd+1+1K0eSk=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=hNzSPjDMsB0uil/ZwIzey4/N2dN3Gr8/enfmU5C3wrkRyaLVSTV5EbcIopK8Fe8gK
	 /fWlIpSvtd/iGu+Dtt6qCCLEYSTSDu4y7VoVyPuUfRdu0C0KrJcRhDXtI1MNK1WX5b
	 P6/zm7vkuU4ijTUIN50Ta+MsAzbJJ2GMmcmZ0gVw=
From: "slyfox at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/104069] Wuse-after-free=2 -O0 false positive "may be
 used"
Date: Fri, 12 May 2023 07:00:45 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Version: 12.0
X-Bugzilla-Keywords: diagnostic
X-Bugzilla-Severity: normal
X-Bugzilla-Who: slyfox at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-104069-4-yNxcdmwtJq@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-104069-4@http.gcc.gnu.org/bugzilla/>
References: <bug-104069-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104069

--- Comment #28 from Sergei Trofimovich <slyfox at gcc dot gnu.org> ---
(In reply to Miklos Karacsony from comment #27)
> (In reply to Sergei Trofimovich from comment #26)
> > #c12 fixed elfutils case.
>=20
> That's not accurate. It's only fixed if you use the default "-O2"
> optimization level, but if you use "-Os" instead, you'll find that the bug
> is still present. I've managed to hit a similar bug while building glibc
> with "-Os" as well, but in that case adding "--disable-werror" helped.
> Sadly, elfutils' configure script does not respect that flag. I could just
> add "-Wno-error" into my cflags when building, but then doing this on a p=
er
> package basis is cumbersome.

I was not able to reproduce -Os build failure on elfutils-0.189. Can you
extract an example from the case you see?=