From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Jason Rumney Newsgroups: gmane.emacs.bugs Subject: bug#8545: issues with recent doprnt-related changes Date: Sun, 01 May 2011 12:25:45 +0800 Message-ID: <87vcxvjbcm.fsf@gnu.org> 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> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1304224622 31370 80.91.229.12 (1 May 2011 04:37:02 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sun, 1 May 2011 04:37:02 +0000 (UTC) Cc: lekktu@gmail.com, 8545@debbugs.gnu.org, rms@gnu.org To: Paul Eggert Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun May 01 06:36:57 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 1QGOOv-0005qx-03 for geb-bug-gnu-emacs@m.gmane.org; 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Sun, 01 May 2011 04:26:01 +0000 Original-Received: (at 8545) by debbugs.gnu.org; 1 May 2011 04:26:01 +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 1QGOEL-0005iM-1x for submit@debbugs.gnu.org; Sun, 01 May 2011 00:26:01 -0400 Original-Received: from mail-px0-f169.google.com ([209.85.212.169]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1QGOEJ-0005i9-3V for 8545@debbugs.gnu.org; Sun, 01 May 2011 00:25:59 -0400 Original-Received: by pxi9 with SMTP id 9so1635019pxi.0 for <8545@debbugs.gnu.org>; Sat, 30 Apr 2011 21:25:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:from:to:cc:subject:references:date :in-reply-to:message-id:user-agent:mime-version:content-type; bh=5ET9mmTKhC6Jdiec/SEoOGHWjKM6o7hwqNI1wxCYC8w=; b=qXhNl8AcqvcTM43Tqsua57jdazkafC6rZOSAZqfTXxOwEC/iF3JG1q7P6y0Owgjy7R mf/fgMJULu1qMaeitUQi2mxYX72bhH4NE7ekOw4xXYM+Fmd8oUrXXi0NT953cmkfnzXh 8oVr0K2S6u8nKC46q9HeoLrwhEi/Enxa3OUXE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version:content-type; b=p2oMo9RWaCZyaPuzqYOZw9aJ615e1nAQAzR3Y84Hp1nyaTB+GKpb/NP9oD9VKF81VB Wzq4UMB8/L+jUHsBhcJsVrVsw8XqooaSb6Mfbb7TNqR8r2TV1dcKH6fW6LgjrG4iMbLG n7WzJ1rC975Gc1yhNPpXfMK59xMNQX1OdY8iY= Original-Received: by 10.68.41.234 with SMTP id i10mr7789477pbl.345.1304223953211; Sat, 30 Apr 2011 21:25:53 -0700 (PDT) Original-Received: from home.jasonrumney.net ([180.75.3.117]) by mx.google.com with ESMTPS id m5sm2946432pbh.70.2011.04.30.21.25.49 (version=TLSv1/SSLv3 cipher=OTHER); Sat, 30 Apr 2011 21:25:51 -0700 (PDT) Original-Received: by home.jasonrumney.net (Postfix, from userid 1000) id BDE983773; Sun, 1 May 2011 12:25:45 +0800 (MYT) In-Reply-To: <4DBB4E80.2020102@cs.ucla.edu> (Paul Eggert's message of "Fri, 29 Apr 2011 16:49:20 -0700") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Resent-Date: Sun, 01 May 2011 00:26:02 -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:46120 Archived-At: Paul Eggert writes: > On 04/29/11 05:28, Richard Stallman wrote: > >> We are concerned with standards insofar as they matter in practice >> for the convenience and reliability of our software. > > Yes, of course, I should have made that clearer. Standards are our > tools, not our masters. > >>> If you assign i = INT_MAX + 1, the resulting behavior is undefined. >> >> The result is INT_MIN. We don't try to support any theoretical machine >> where this would not be so. > > long > foo (char *p, int i) > { > return &p[i + 1] - &p[i]; > } > > On typical hosts where int is 32 bits, and long and char * are > both 64 bits, most compilers optimize that "return" statement > to "return 1;", even when I is INT_MAX and I + 1 therefore > overflows. That does not mean that INT_MAX + 1 is undefined. You are also involving implicit casts here. Exactly where those casts happen is what is undefined.