From nobody Mon Jan 5 01:31:08 2026 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4dkxbH4dc2z6N9jY; Mon, 05 Jan 2026 01:31:23 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4dkxbH12nWz43g8; Mon, 05 Jan 2026 01:31:23 +0000 (UTC) (envelope-from kostikbel@gmail.com) Authentication-Results: mx1.freebsd.org; none Received: from tom.home (kib@localhost [127.0.0.1] (may be forged)) by kib.kiev.ua (8.18.1/8.18.1) with ESMTP id 6051V8Y2083427; Mon, 5 Jan 2026 03:31:11 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 6051V8Y2083427 Received: (from kostik@localhost) by tom.home (8.18.1/8.18.1/Submit) id 6051V8qk083426; Mon, 5 Jan 2026 03:31:08 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Mon, 5 Jan 2026 03:31:08 +0200 From: Konstantin Belousov To: Robert Clausecker Cc: src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-branches@freebsd.org Subject: Re: git: 9c68745a5064 - stable/15 - libc/amd64: fix stpncpy.S again Message-ID: References: <695a69f1.39da1.5b9f90d9@gitrepo.freebsd.org> List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <695a69f1.39da1.5b9f90d9@gitrepo.freebsd.org> X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=4.0.2 X-Spam-Checker-Version: SpamAssassin 4.0.2 (2025-08-27) on tom.home X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Rspamd-Queue-Id: 4dkxbH12nWz43g8 On Sun, Jan 04, 2026 at 01:24:01PM +0000, Robert Clausecker wrote: > The branch stable/15 has been updated by fuz: > > URL: https://cgit.FreeBSD.org/src/commit/?id=9c68745a50640ccff37565e3cbfe53dddc18d7d3 > > commit 9c68745a50640ccff37565e3cbfe53dddc18d7d3 > Author: Robert Clausecker > AuthorDate: 2025-12-18 23:37:33 +0000 > Commit: Robert Clausecker > CommitDate: 2026-01-04 13:22:51 +0000 > > libc/amd64: fix stpncpy.S again > > The previous fix introduced a regression on machines without the BMI1 > instruction set extension. The TZCNT instruction used in this function > behaves different on old machines when the source operand is zero, but > the code was originally designed to never trigger this case. The bug > fix caused this case to be possible, leading to a regression on > sufficiently old hardware. > > Fix the code by messing with things such that the source operand is > never zero. > > PR: 291720 > Fixes: 66eb78377bf109af1d9e25626bf254b4369436ec > Tested by: cy > Approved by: markj (mentor) > Differential Revision: https://reviews.freebsd.org/D54303 > > (cherry picked from commit 2f83319214d9adb8ab7a77e35d1014658b3f9cae) Why do you perform insta-MFC? Even for bug fixes, the strict policy is to have at least 3 days probation for the change in HEAD.