From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#17986: 24.3.92; Evaluating (setq default-directory nil) freezes Emacs Date: Tue, 15 Jul 2014 17:27:48 +0300 Message-ID: <83fvi28zob.fsf@gnu.org> References: <87pphdwg99.fsf@rosalinde.fritz.box> <834myl9ums.fsf@gnu.org> <871ttm97e9.fsf@rosalinde.fritz.box> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1405434509 8428 80.91.229.3 (15 Jul 2014 14:28:29 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 15 Jul 2014 14:28:29 +0000 (UTC) Cc: 17986@debbugs.gnu.org To: Stephen Berman Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Jul 15 16:28:22 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1X73iM-0008Gq-TM for geb-bug-gnu-emacs@m.gmane.org; Tue, 15 Jul 2014 16:28:19 +0200 Original-Received: from localhost ([::1]:34994 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X73iM-000286-FP for geb-bug-gnu-emacs@m.gmane.org; Tue, 15 Jul 2014 10:28:18 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:33633) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X73iD-0001yv-6L for bug-gnu-emacs@gnu.org; Tue, 15 Jul 2014 10:28:15 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X73i6-0000Hh-M1 for bug-gnu-emacs@gnu.org; Tue, 15 Jul 2014 10:28:09 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:60463) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X73i6-0000Hd-GE for bug-gnu-emacs@gnu.org; Tue, 15 Jul 2014 10:28:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1X73i5-0003Yr-Ql for bug-gnu-emacs@gnu.org; Tue, 15 Jul 2014 10:28:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 15 Jul 2014 14:28:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17986 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 17986-submit@debbugs.gnu.org id=B17986.140543447013666 (code B ref 17986); Tue, 15 Jul 2014 14:28:01 +0000 Original-Received: (at 17986) by debbugs.gnu.org; 15 Jul 2014 14:27:50 +0000 Original-Received: from localhost ([127.0.0.1]:55729 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1X73hq-0003YF-4L for submit@debbugs.gnu.org; Tue, 15 Jul 2014 10:27:50 -0400 Original-Received: from mtaout25.012.net.il ([80.179.55.181]:42464) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1X73hk-0003Xu-IM for 17986@debbugs.gnu.org; Tue, 15 Jul 2014 10:27:44 -0400 Original-Received: from conversion-daemon.mtaout25.012.net.il by mtaout25.012.net.il (HyperSendmail v2007.08) id <0N8R00200BVHMV00@mtaout25.012.net.il> for 17986@debbugs.gnu.org; Tue, 15 Jul 2014 17:23:13 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by mtaout25.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0N8R00IJQBYOFL90@mtaout25.012.net.il>; Tue, 15 Jul 2014 17:23:13 +0300 (IDT) In-reply-to: <871ttm97e9.fsf@rosalinde.fritz.box> X-012-Sender: halo1@inter.net.il X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x 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:91562 Archived-At: > From: Stephen Berman > Cc: 17986@debbugs.gnu.org > Date: Tue, 15 Jul 2014 13:41:02 +0200 > > On Sun, 13 Jul 2014 17:54:35 +0300 Eli Zaretskii wrote: > > >> From: Stephen Berman > >> Date: Thu, 10 Jul 2014 14:27:30 +0200 > >> > >> 0. Start Emacs with -Q or -Q -D > >> 1. Type (setq default-directory nil) in *scratch* and evaluate it. > >> => Emacs freezes uninterruptibly and uses up to 90% CPU; I have to kill > >> it from outside. > > > > Should be fixed in revision 117376 on the emacs-24 branch. > > For the record, I confirm that this fixes it; thanks. Thanks for verification. > > When Emacs becomes unresponsive, it is best to attach a debugger to a > > running Emacs process, and then use the procedure described in > > etc/DEBUG (under "If the symptom of the bug is that Emacs fails to > > respond") to find out which function infloops; then include this > > information in the bug report. > > I tried doing this, but neither with `s' nor with `f' did gdb show what > I could recognize as an infloop (`f' always went straight to frame #0, > and `s' never got to a loop, though I entered it very many times). Is > there something more specific I could do the next time? etc/DEBUG doesn't say to use `s' and `f', it says to use 'finish' and 'next'. 'f' is not an abbreviation of 'finish', it is an abbreviation of 'frame'. Also, 'step', or 's', is not useful in this situation, because it simply undoes what you did with 'finish', by getting you deeper and deeper into the code from which you just emerged. The idea of that procedure is to first find the function where Emacs loops, by repeated 'finish' commands until 'finish' doesn't return, i.e. does not print a higher frame number and the value returned by the lower frame. Then step with 'next' through the looping function and see why it loops, i.e. why it fails to return. (In this case, it failed to return because displaying the mode line signaled an error, which immediately triggered another redisplay.)