From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 0B6DE3857730; Fri, 26 May 2023 21:40:44 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0B6DE3857730 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1685137245; bh=+w3ajjzE+tj3uPg7L2SrO/OhzAF3CWp5Fe5U3HVAMNI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=yPrYbDugXJr9WOsEfaMf8MgFAY2zYdu4qrd6mFsXPJMYPxKOYeXa2Ue8yMKNvyI9d qTJdVTFSE2208sY37MsT3LWjILlm5PEr/ZNE7LZjNeSAulj/7Zu+OdafWqVf36TUWi xfzG22CRI01h3Rg0YmgGGLXTvIujMvUtEK4O18ZE= From: "urisimchoni at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/105562] [12 Regression] std::function::_M_invoker may be used uninitialized in std::regex move with -fno-strict-aliasing Date: Fri, 26 May 2023 21:40:43 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libstdc++ X-Bugzilla-Version: 12.1.0 X-Bugzilla-Keywords: diagnostic, missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: urisimchoni at gmail dot com X-Bugzilla-Status: RESOLVED X-Bugzilla-Resolution: FIXED X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org X-Bugzilla-Target-Milestone: 12.2 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: 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: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105562 Uri Simchoni changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |urisimchoni at gmail dot c= om --- Comment #21 from Uri Simchoni --- (In reply to Richard Biener from comment #18) > (In reply to Sven Hesse from comment #17) > > I still get this with gcc 12.2.0 (Gentoo 12.2.0 p9), but only when comp= iling > > with (at least with) -O1 -fsanitize=3Daddress, in addition to any warni= ng flag > > that enables -Wmaybe-uninitialized (like -Wall, -Wextra or -Wuninitiali= zed). > >=20 > > -O0 and/or no ASan, and the offending code compiles cleanly without any > > warnings. Somehow, the combination of enabling ASan and optimization > > (anything > -O0, but not -Os) triggers it again, it seems? > >=20 > > I can observe this with the testcase attached here in this bug report. >=20 > -fsanitize=3Daddress is likely to derail optimization enough to make such > occurences more likely, I think we have plenty of duplicate bugreports > for this. So it seems this is still hapening with -O1 -fsanitize=3Daddress (occurring= for me too with GCC 13.1.0), yet this specific bug is marked as "fixed" and the= re's a mention of duplicate bugreports (I can see one unconfirmed pointed-to by = this issue). Is opening of another bug, focusing on -O1 -fsanitize=3Daddress, go= ing to help get this fixed?=