From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id B1DC438582BC; Thu, 4 Jan 2024 14:44:25 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B1DC438582BC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1704379465; bh=6p2FYp0KB4VUN2TEb2CSquWvBPxe0l874ncHak33bnI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=vwfldxRv1tgfvokfd8vtTLNIYgPB4lG03siL8Cwc4ymbRo5xNqGdL3hAq04ZTW5QD 4Fp7CHHVmgvkq4LhToRdkCwI5+v6J0O6AljcwgPAVj7Ch/nIBVxDQXw3NYDTAA3Pui DnR9YNeX8VKWqkhfJCe811/IDHA+RWAMPahj9aFE= From: "bugdal at aerifal dot cx" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/32667] block copy with exact overlap is expanded as memcpy Date: Thu, 04 Jan 2024 14:44:24 +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: 4.2.0 X-Bugzilla-Keywords: documentation, wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: bugdal at aerifal dot cx 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: 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=3D32667 --- Comment #62 from Rich Felker --- The process described there would have to end at least N bits before the en= d of the destination buffer. The point was that it would destroy information internal to the buffer at each step along the way, before it got to the end= .=