From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id DB9B33858D33; Thu, 2 May 2024 13:24:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DB9B33858D33 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1714656288; bh=O7gsu0R220cyTuCPjqLRvcl2lxy6GLFccMjLiV6/grk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=EYKItpRnV8E89OOeNHYHHMEy2t5QhcPftykYeXnCOXp0uTxBXDGGLi0v1yFQJbG/m k7tdpDt+oJpCsDUQiE3fKaUAjv5MNQnGYmgNZ//qgeEdnncZArUBJ0uSi5qFT2Qy+B csP3URCpS5+VJQia0mlAgLR7PMH30V7nAX48JKY4= From: "amonakov at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/114923] gcc ignores escaping pointer and applies invalid optimization Date: Thu, 02 May 2024 13:24:48 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: unknown X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: amonakov at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED 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: 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=3D114923 Alexander Monakov changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |amonakov at gcc dot gnu.org --- Comment #2 from Alexander Monakov --- 'volatile' is not viral like that. If 'buf' can be accessed outside of the abstract machine, it needs to be volatile itself. Alternatively, an empty a= sm with a memory clobber, asm("":::"memory"), will imply a possible access to 'buf' via its escaped address.=