From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.bugs Subject: bug#8545: issues with recent doprnt-related changes Date: Sat, 30 Apr 2011 22:56:45 -0700 Organization: UCLA Computer Science Department Message-ID: <4DBCF61D.50000@cs.ucla.edu> References: <4DB50AB9.6060100@cs.ucla.edu> <83tydmaeo3.fsf@gnu.org> <4DB65FF1.5010003@cs.ucla.edu> <83aafb8p4a.fsf@gnu.org> <4DB8ABEA.3080503@cs.ucla.edu> <4DB8DAF8.7070408@cs.ucla.edu> <4DBB4E80.2020102@cs.ucla.edu> <87vcxvjbcm.fsf@gnu.org> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Trace: dough.gmane.org 1304230026 18056 80.91.229.12 (1 May 2011 06:07:06 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sun, 1 May 2011 06:07:06 +0000 (UTC) Cc: lekktu@gmail.com, 8545@debbugs.gnu.org, rms@gnu.org To: Jason Rumney Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun May 01 08:07:00 2011 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([140.186.70.17]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1QGPo2-0001TX-Ry for geb-bug-gnu-emacs@m.gmane.org; Sun, 01 May 2011 08:06:58 +0200 Original-Received: from localhost ([::1]:38199 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QGPo2-0004pJ-71 for geb-bug-gnu-emacs@m.gmane.org; Sun, 01 May 2011 02:06:58 -0400 Original-Received: from eggs.gnu.org ([140.186.70.92]:60526) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QGPny-0004mU-2X for bug-gnu-emacs@gnu.org; Sun, 01 May 2011 02:06:54 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QGPnw-00008S-UX for bug-gnu-emacs@gnu.org; Sun, 01 May 2011 02:06:53 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:44779) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QGPnw-00008O-Su for bug-gnu-emacs@gnu.org; Sun, 01 May 2011 02:06:52 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.69) (envelope-from ) id 1QGPeP-0007gP-MU; Sun, 01 May 2011 01:57:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Paul Eggert Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-To: owner@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 01 May 2011 05:57:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 8545 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 8545-submit@debbugs.gnu.org id=B8545.130422941429516 (code B ref 8545); Sun, 01 May 2011 05:57:01 +0000 Original-Received: (at 8545) by debbugs.gnu.org; 1 May 2011 05:56:54 +0000 Original-Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1QGPeH-0007g1-SK for submit@debbugs.gnu.org; Sun, 01 May 2011 01:56:54 -0400 Original-Received: from smtp.cs.ucla.edu ([131.179.128.62]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1QGPeF-0007fp-QK for 8545@debbugs.gnu.org; Sun, 01 May 2011 01:56:52 -0400 Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 31C0F39E80F8; Sat, 30 Apr 2011 22:56:46 -0700 (PDT) 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 YxgwXeISZyNy; Sat, 30 Apr 2011 22:56:45 -0700 (PDT) Original-Received: from [192.168.1.10] (pool-71-189-109-235.lsanca.fios.verizon.net [71.189.109.235]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id AE00B39E80F2; Sat, 30 Apr 2011 22:56:45 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.14) Gecko/20110223 Thunderbird/3.1.8 In-Reply-To: <87vcxvjbcm.fsf@gnu.org> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Resent-Date: Sun, 01 May 2011 01:57:01 -0400 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 140.186.70.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:46122 Archived-At: On 04/30/11 21:25, Jason Rumney wrote: > You are also > involving implicit casts here. Exactly where those casts happen is what > is undefined. I'm not sure what is meant here, as the program in question doesn't have any implicit arithmetic conversions (or at least, it doesn't on the typical 64-bit host I was talking about). > That does not mean that INT_MAX + 1 is undefined. It could well be that the exact expression "INT_MAX + 1" has well-defined behavior on all platforms we care about, and that it always returns INT_MIN. But I'm concerned about the more general issue, which is whether Emacs code can always assume that signed integer arithmetic wraps around. Unfortunately, there are many practical Emacs targets where it's incorrect to assume that.