From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: pdumper.c Wstringop-overflow warnings with CFLAGS="-O3" [Re: Emacs 29.2 released] Date: Fri, 19 Jan 2024 09:23:44 +0200 Message-ID: <83il3pwzun.fsf@gnu.org> References: <83ttnaaojz.fsf@gnu.org> <87a5p23xtc.fsf@moondust.localdomain> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="20972"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: "N. Jackson" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Jan 19 08:24:28 2024 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rQjEp-0005Gb-Po for ged-emacs-devel@m.gmane-mx.org; Fri, 19 Jan 2024 08:24:27 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rQjEE-0000m4-AC; Fri, 19 Jan 2024 02:23:50 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rQjEC-0000lp-Q4 for emacs-devel@gnu.org; Fri, 19 Jan 2024 02:23:49 -0500 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rQjEC-0003fu-8F; Fri, 19 Jan 2024 02:23:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=References:Subject:In-Reply-To:To:From:Date: mime-version; bh=3zbfxgYWaF5+ajnraHFJstuCjhmTmF6jYHs7pQGFKpo=; b=QrMM01CmvhjT lm9kcYgiKea0YAheG2bQvDqVhuE79EELicgmDnIQ7ZYgtQmrH86ppaLTnAcEP3mOEQrnf4bcdF1Jy mzuFXZIf780d2YWfJ2GTqWqnGCrLl55wc9GtLFgmIdg8dJRZ0yYKN5iVIvk2Q0rIYn8iRhbCVGL1o SWfBm87NubMKg2G0blzdasS4oeCPaE8EoaH5H6lrgj4Z1QQHOP/3sBjau35aYFNxLfCRbzGY7/I6j caghiPC5wR7FDbXAwZMt3LUtbhcaRK0CM26DijSmAf9pyMmmggiHo4Kqqq0RI8xnAX397ukvQ10m/ jE6tCUk/WSlnoXbZ610xrg==; In-Reply-To: <87a5p23xtc.fsf@moondust.localdomain> (njackson@posteo.net) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:315106 Archived-At: > From: "N. Jackson" > Date: Fri, 19 Jan 2024 01:40:31 +0000 > > > At 13:06 +0200 on Thursday 2024-01-18, Eli Zaretskii wrote: > > > > Version 29.2 of Emacs, the extensible text editor, should now > > be available > > Thank you Eli for your stalwart maintenance of Emacs and to everyone > else who has contributed recently (and, indeed, ever). > > Building Emacs 29.2 with CFLAGS="-O3" I get four Wstringop-overflow > warnings in pdumper.c (see below). Can I (as an Emacs user) safely > ignore these warnings? Note: I don't get these warnings with > CFLAGS="-O2". If someone wants to investigate these warnings, please do. My sincere suggestion is not to build Emacs with -O3 regardless: it is not going to give you a faster Emacs, and might even give you a slower Emacs. That's because the inner-most loops in Emacs are very large, and the optimization techniques used by -O3 are likely not to work well, while at the same time the excessive inlining might make those loops larger and thus overflow the CPU caches, which slows down code execution. Thanks.