From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: Warnings/errors related to possibly clobbered variables Date: Tue, 13 Jan 2015 13:31:55 -0800 Organization: UCLA Computer Science Department Message-ID: <54B58ECB.7010403@cs.ucla.edu> References: <54B50246.2070507@yandex.ru> <54B50BC4.3060302@yandex.ru> <83k30q4pnn.fsf@gnu.org> <83egqy4f36.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1421184743 24347 80.91.229.3 (13 Jan 2015 21:32:23 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 13 Jan 2015 21:32:23 +0000 (UTC) Cc: schwab@suse.de, dmantipov@yandex.ru, emacs-devel@gnu.org To: Eli Zaretskii , Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Jan 13 22:32:16 2015 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1YB94R-00081w-Rc for ged-emacs-devel@m.gmane.org; Tue, 13 Jan 2015 22:32:15 +0100 Original-Received: from localhost ([::1]:41519 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YB94R-000663-1w for ged-emacs-devel@m.gmane.org; Tue, 13 Jan 2015 16:32:15 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55492) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YB94D-00065t-I5 for emacs-devel@gnu.org; Tue, 13 Jan 2015 16:32:02 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YB94C-00014V-NE for emacs-devel@gnu.org; Tue, 13 Jan 2015 16:32:01 -0500 Original-Received: from smtp.cs.ucla.edu ([131.179.128.62]:50262) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YB949-000146-Ip; Tue, 13 Jan 2015 16:31:57 -0500 Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id DE8B0A60115; Tue, 13 Jan 2015 13:31:55 -0800 (PST) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Original-Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZMNLVawRg06d; Tue, 13 Jan 2015 13:31:55 -0800 (PST) Original-Received: from Penguin.CS.UCLA.EDU (Penguin.CS.UCLA.EDU [131.179.64.200]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id AB709A60110; Tue, 13 Jan 2015 13:31:55 -0800 (PST) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 In-Reply-To: <83egqy4f36.fsf@gnu.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 131.179.128.62 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:181239 Archived-At: On 01/13/2015 12:10 PM, Eli Zaretskii wrote: > The compiler is rarely wrong in these cases But it does appear to be wrong in this case. That's why I filed a compiler bug, and the GCC maintainers seem to agree that it's a bug. Long ago when I ran into this set of GCC bugs, I shrugged and added 'volatile's to pacify the buggy GCCs. Stefan removed some of them as part of some of his other fixes, but I suspect that a few 'volatile's are not necessary even today (except perhaps to pacify the GCC bug). I say "set of GCC bugs" because I suspect there are more than one, some of which have been fixed, and some of which remain.