From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Should undefined behavior be encouraged in Emacs? Date: Sun, 02 Oct 2011 23:11:58 -0400 Message-ID: References: <4E89124D.8070405@cs.ucla.edu> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1317611538 9807 80.91.229.12 (3 Oct 2011 03:12:18 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Mon, 3 Oct 2011 03:12:18 +0000 (UTC) Cc: Emacs Development To: Paul Eggert Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Oct 03 05:12:14 2011 Return-path: Envelope-to: ged-emacs-devel@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 1RAYwq-0003sb-W3 for ged-emacs-devel@m.gmane.org; Mon, 03 Oct 2011 05:12:09 +0200 Original-Received: from localhost ([::1]:51200 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAYwq-00066G-21 for ged-emacs-devel@m.gmane.org; Sun, 02 Oct 2011 23:12:08 -0400 Original-Received: from eggs.gnu.org ([140.186.70.92]:47044) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAYwn-00064n-TH for emacs-devel@gnu.org; Sun, 02 Oct 2011 23:12:06 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RAYwm-0005pu-Mo for emacs-devel@gnu.org; Sun, 02 Oct 2011 23:12:05 -0400 Original-Received: from ironport2-out.teksavvy.com ([206.248.154.181]:13904 helo=ironport2-out.pppoe.ca) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAYwm-0005ph-KA for emacs-devel@gnu.org; Sun, 02 Oct 2011 23:12:04 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Av0EAK8niU5FpZLc/2dsb2JhbABBDqgBgQaBUwEBBAFWIwULCzQSFBgNJIgOtxOHIQSgd4NwUw X-IronPort-AV: E=Sophos;i="4.68,478,1312171200"; d="scan'208";a="139710377" Original-Received: from 69-165-146-220.dsl.teksavvy.com (HELO ceviche.home) ([69.165.146.220]) by ironport2-out.pppoe.ca with ESMTP/TLS/ADH-AES256-SHA; 02 Oct 2011 23:11:58 -0400 Original-Received: by ceviche.home (Postfix, from userid 20848) id 4B1DF660B6; Sun, 2 Oct 2011 23:11:58 -0400 (EDT) In-Reply-To: <4E89124D.8070405@cs.ucla.edu> (Paul Eggert's message of "Sun, 02 Oct 2011 18:39:25 -0700") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 206.248.154.181 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:144532 Archived-At: > The argument given for undefined behavior is that it simplifies > maintenance of Emacs internals. I like to keep some corner of the behavior undefined, when I think that user code that depends on such details is undesirable (e.g. return values of primitives which are only called for side-effects). Stefan