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#17168: 24.3.50; Segfault at mark_object Date: Sun, 06 Apr 2014 19:59:29 +0300 Message-ID: <83y4zi75se.fsf@gnu.org> References: <87y4zop44m.fsf@yahoo.fr> <533C3AF5.6070502@yandex.ru> <533C6905.9060309@dancol.org> <83bnwjbh8v.fsf@gnu.org> <533C75A6.60900@dancol.org> <533D06E6.2060001@yandex.ru> <533D07EF.1040502@yandex.ru> <533D13E2.3060300@dancol.org> <533D251E.3030108@dancol.org> <533D6A19.8050504@yandex.ru> <533D9099.3000104@dancol.org> <533D9F2C.7030500@yandex.ru> <533D9FBB.2050803@dancol.org> <533DB4F0.20706@dancol.org> <534085B1.9070307@dancol.org> <838uri8pkf.fsf@gnu.org> <534179FB.4090301@dancol.org> <834n268m7r.fsf@gnu.org> <53417FA1.1060100@dancol.org> <83zjjy7763.fsf@gnu.org> <534182C3.30205@dancol.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1396803626 6172 80.91.229.3 (6 Apr 2014 17:00:26 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 6 Apr 2014 17:00:26 +0000 (UTC) Cc: dmantipov@yandex.ru, 17168@debbugs.gnu.org To: Daniel Colascione Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Apr 06 19:00:20 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 1WWqQc-0000W1-Gv for geb-bug-gnu-emacs@m.gmane.org; Sun, 06 Apr 2014 19:00:18 +0200 Original-Received: from localhost ([::1]:58718 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WWqQc-0002VK-9V for geb-bug-gnu-emacs@m.gmane.org; Sun, 06 Apr 2014 13:00:18 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:33638) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WWqQU-0002SY-Ar for bug-gnu-emacs@gnu.org; Sun, 06 Apr 2014 13:00:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WWqQP-0003E9-K9 for bug-gnu-emacs@gnu.org; Sun, 06 Apr 2014 13:00:10 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:37086) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WWqQP-0003CL-HN for bug-gnu-emacs@gnu.org; Sun, 06 Apr 2014 13:00:05 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WWqQN-0004Sv-SR for bug-gnu-emacs@gnu.org; Sun, 06 Apr 2014 13:00:04 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 06 Apr 2014 17:00:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17168 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: moreinfo Original-Received: via spool by 17168-submit@debbugs.gnu.org id=B17168.139680358717110 (code B ref 17168); Sun, 06 Apr 2014 17:00:03 +0000 Original-Received: (at 17168) by debbugs.gnu.org; 6 Apr 2014 16:59:47 +0000 Original-Received: from localhost ([127.0.0.1]:38268 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WWqQ6-0004Rt-Fi for submit@debbugs.gnu.org; Sun, 06 Apr 2014 12:59:46 -0400 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:36909) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WWqQ3-0004Ri-SV for 17168@debbugs.gnu.org; Sun, 06 Apr 2014 12:59:45 -0400 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0N3M00400CBGQ900@a-mtaout21.012.net.il> for 17168@debbugs.gnu.org; Sun, 06 Apr 2014 19:59:42 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0N3M0044LCJHP240@a-mtaout21.012.net.il>; Sun, 06 Apr 2014 19:59:42 +0300 (IDT) In-reply-to: <534182C3.30205@dancol.org> 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:87813 Archived-At: > Date: Sun, 06 Apr 2014 09:37:23 -0700 > From: Daniel Colascione > CC: monnier@IRO.UMontreal.CA, dmantipov@yandex.ru, 17168@debbugs.gnu.org > > > Because Richard has been using that machine for years, and I very much > > doubt that he changed his usage patterns lately. > > Richard's not the only one who has seen this crash. Drew's also reported > GC crashes in odd, and different, places. Which seem unrelated, and started much later than Richard reported his. > >>>>> In http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15583#23, Richard > >>>>> provided the last good revno (113938) and the first bad one (114268); > >>>>> I looked at that range of revisions, and 114156 looks relevant. How > >>>>> about if we revert it and see if the problems go away? > >>>> > >>>> The bug would still be there, and we'd have no way to tell whether your > >>>> proposed change actually reduced its occurrence to a tolerable level. > >>>> Why would you want to do that instead of just fixing the bug? > >>> > >>> Because it's simpler, > >> > >> It's easy to make code that's simple and wrong. > > > > I didn't suggest any new code. > > No: you're just suggesting leaving incorrect code in Emacs. It's not incorrect, AFAIU. It might be less optimal. > >>> and because it just might be that the bug was > >>> caused by that other changeset. > >> > >> How might that changeset in particular have caused the problem reports? > > > > It is related to calling a function, and is in the same function from > > which all the recent crashes started. > > You haven't identified a causal mechanism. Any recent change could have > caused enough of a shift in code generation or stack layout to cause > this problem, and because it manifests so seldom, it'd be hard to verify > that reverting any particular change "fixed" the problem. I thought you had a test case. If not, how did you verify that your suggested changes do fix the problem? > Also, eval_sub does *everything*. It's no surprise that we saw the > crashes there. That's like saying "all crashes are associated with main, > this change affects main, and therefore this change is responsible." The change is related to calling a function whose symbol has certain properties. That sounds related to me, not just a random change somewhere in eval_sub. Anyway, it was just an idea which I thought would be easy to try.