From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#24640: Crashes in 25.1 Date: Tue, 11 Oct 2016 14:59:07 +0300 Message-ID: <83lgxvcd10.fsf@gnu.org> References: <83int3idxl.fsf@gnu.org> <83mviehq0p.fsf@gnu.org> <83eg3qhn29.fsf@gnu.org> <83vax2f1e5.fsf@gnu.org> <83r37pg7zl.fsf@gnu.org> <83y41wenld.fsf@gnu.org> <834m4kduzl.fsf@gnu.org> <831szodsus.fsf@gnu.org> <83zimccbzr.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1476187228 24497 195.159.176.226 (11 Oct 2016 12:00:28 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 11 Oct 2016 12:00:28 +0000 (UTC) Cc: 24640@debbugs.gnu.org To: Reuben Thomas Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Oct 11 14:00:25 2016 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1btvjE-0004v9-Kc for geb-bug-gnu-emacs@m.gmane.org; Tue, 11 Oct 2016 14:00:16 +0200 Original-Received: from localhost ([::1]:55151 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1btvjD-0007Zz-9a for geb-bug-gnu-emacs@m.gmane.org; Tue, 11 Oct 2016 08:00:15 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:43431) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1btvj5-0007Wr-87 for bug-gnu-emacs@gnu.org; Tue, 11 Oct 2016 08:00:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1btvj1-0002U1-8t for bug-gnu-emacs@gnu.org; Tue, 11 Oct 2016 08:00:07 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:45598) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1btvj1-0002Tm-5o for bug-gnu-emacs@gnu.org; Tue, 11 Oct 2016 08:00:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1btvj0-00087s-Tw for bug-gnu-emacs@gnu.org; Tue, 11 Oct 2016 08:00:02 -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, 11 Oct 2016 12:00:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 24640 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 24640-submit@debbugs.gnu.org id=B24640.147618717831180 (code B ref 24640); Tue, 11 Oct 2016 12:00:02 +0000 Original-Received: (at 24640) by debbugs.gnu.org; 11 Oct 2016 11:59:38 +0000 Original-Received: from localhost ([127.0.0.1]:51788 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1btvic-00086p-Ml for submit@debbugs.gnu.org; Tue, 11 Oct 2016 07:59:38 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:52349) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1btvib-00086c-2R for 24640@debbugs.gnu.org; Tue, 11 Oct 2016 07:59:37 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1btviR-00022C-Rb for 24640@debbugs.gnu.org; Tue, 11 Oct 2016 07:59:31 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:36326) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1btviR-00021Z-Nk; Tue, 11 Oct 2016 07:59:27 -0400 Original-Received: from 84.94.185.246.cable.012.net.il ([84.94.185.246]:1344 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1btviP-0007nI-3i; Tue, 11 Oct 2016 07:59:26 -0400 In-reply-to: (message from Reuben Thomas on Mon, 10 Oct 2016 22:35:55 +0100) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 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" Xref: news.gmane.org gmane.emacs.bugs:124330 Archived-At: Thanks, I've done some initial debugging. The crash seems to be related to the variable read_objects, defined and used by lread.c. It is an alist of objects read with the #n=object form. One of its members is a corrupted Lisp object, which causes the GC crash when this object is examined. read_objects is a global variable, so it could be that some code invoked in the middle of reading one #n=object form clobbers it by reading another. However, I don't immediately see such forms in the few of your many init files I looked in. Do you have any idea where this could come from? One place they are abundant is in *.elc files, so maybe some recursive load together with the timer-based lazy desktop operation does that? I don't really have a working hypothesis for now. I'm not an expert on X tricks -- is there any way you can trick Emacs to start a GUI session when I invoke it via SSH? Some trick with the value of DISPLAY in the environment, perhaps? I don't need to see what Emacs displays, just run it live under GDB. The problem that causes the crash happens before the code I see in the backtrace -- that code just triggers GC. So it would be beneficial to run Emacs under GDB and try to see, for example, what code changes read_objects and how (assuming it is not changed to a non-nil value too many times). Can this be arranged? Thanks.