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: apparent infloop in re_match_2_internal Date: Thu, 17 Dec 2009 09:36:51 -0500 Message-ID: References: <87fx7botb3.fsf@meyering.net> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1261060998 19908 80.91.229.12 (17 Dec 2009 14:43:18 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 17 Dec 2009 14:43:18 +0000 (UTC) Cc: Jim Meyering , Emacs development discussions To: Andreas Schwab Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Dec 17 15:43:11 2009 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1NLHZO-0000oI-39 for ged-emacs-devel@m.gmane.org; Thu, 17 Dec 2009 15:43:10 +0100 Original-Received: from localhost ([127.0.0.1]:36755 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NLHZN-0006fl-J9 for ged-emacs-devel@m.gmane.org; Thu, 17 Dec 2009 09:43:09 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NLHTe-00016I-7X for emacs-devel@gnu.org; Thu, 17 Dec 2009 09:37:14 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NLHTZ-0000xC-4c for emacs-devel@gnu.org; Thu, 17 Dec 2009 09:37:13 -0500 Original-Received: from [199.232.76.173] (port=37854 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NLHTY-0000wf-NX for emacs-devel@gnu.org; Thu, 17 Dec 2009 09:37:08 -0500 Original-Received: from chene.dit.umontreal.ca ([132.204.246.20]:39762) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NLHTY-0004OI-Eo for emacs-devel@gnu.org; Thu, 17 Dec 2009 09:37:08 -0500 Original-Received: from alfajor.home (faina.iro.umontreal.ca [132.204.26.177]) by chene.dit.umontreal.ca (8.14.1/8.14.1) with ESMTP id nBHEav9F027575; Thu, 17 Dec 2009 09:37:02 -0500 Original-Received: by alfajor.home (Postfix, from userid 20848) id 54F206428A; Thu, 17 Dec 2009 09:36:51 -0500 (EST) In-Reply-To: (Andreas Schwab's message of "Wed, 16 Dec 2009 17:56:47 +0100") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1.90 (gnu/linux) X-NAI-Spam-Score: 0 X-NAI-Spam-Rules: 1 Rules triggered RV3429=0 X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 3) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:118673 Archived-At: >> In emacs.git (again from ~3 days ago, debian unstable), >> using GNUS, when I try to reply to a certain message, I >> get into what looks like an unbreakable infinite loop. > What's the regexp? Apparent inf-looping in regexp matching is common because we use a backtracking search (hence with really bad worst case behavior). This is a problem in itself, but we've lived with it for a long time now. The problem in his report is that additionally C-g failed to work. Can you check the value of Vinhibit_quit and show us the xbacktrace to see if the reason C-g didn't work is because we're in an inhibit-quit context and if so which one? If the inhibit-quit is really needed there, then we'll indeed have to fix the regexp to not trigger the worst-case behavior. Stefan