From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Sam Halliday Newsgroups: gmane.emacs.help Subject: help debugging a segfault Date: Mon, 17 Oct 2016 13:16:33 -0700 (PDT) Message-ID: NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1476735871 7200 195.159.176.226 (17 Oct 2016 20:24:31 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 17 Oct 2016 20:24:31 +0000 (UTC) Injection-Date: Mon, 17 Oct 2016 20:16:34 +0000 User-Agent: G2/1.0 To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Oct 17 22:24:24 2016 Return-path: Envelope-to: geh-help-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 1bwES0-0006gC-DN for geh-help-gnu-emacs@m.gmane.org; Mon, 17 Oct 2016 22:24:00 +0200 Original-Received: from localhost ([::1]:35754 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bwES2-0007pi-6K for geh-help-gnu-emacs@m.gmane.org; Mon, 17 Oct 2016 16:24:02 -0400 X-Received: by 10.200.44.134 with SMTP id 6mr7631525qtw.31.1476735394043; Mon, 17 Oct 2016 13:16:34 -0700 (PDT) X-Received: by 10.36.20.207 with SMTP id 198mr272080itg.5.1476735393975; Mon, 17 Oct 2016 13:16:33 -0700 (PDT) Original-Path: usenet.stanford.edu!f6no1930302qtd.0!news-out.google.com!203ni1127itk.0!nntp.google.com!66no486091itl.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Original-Newsgroups: gnu.emacs.help Complaints-To: groups-abuse@google.com Original-Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=82.8.192.163; posting-account=kRukCAoAAAANs-vsVh9dFwo5kp5pwnPz Original-NNTP-Posting-Host: 82.8.192.163 Original-Xref: usenet.stanford.edu gnu.emacs.help:218994 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.org gmane.emacs.help:111553 Archived-At: Hi all, Despite being very stable since I installed it when released, Emacs 25.1 ha= s started to segfault on me this week in a hard-to-reproduce manner. I use ArchLinux and I recompiled with debugging symbols to obtain a detaile= d core dump / crash log. But this is all I got when running with gdb until it crashed: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D Thread 1 "emacs" received signal SIGSEGV, Segmentation fault. re_search_2 (bufp=3Dbufp@entry=3D0xc2d460 , str1=3Dstr1@en= try=3D0x597b790 , size1= =3Dsize1@entry=3D0,=20 str2=3Dstr2@entry=3D0x597b790 , size2=3D65565, startpos=3D646, startpos@entry=3D623, range=3D509= ,=20 regs=3D0xc2c8d0 , stop=3D1155) at regex.c:4464 4464 int len =3D BYTES_BY_CHAR_HEAD (*p); =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D When this happens I have just typed `M-x ensime` and it seems like emacs is= crashing when loading the .ensime file, which is an s-expression file that= is loaded as data in https://github.com/ensime/ensime-emacs/blob/master/en= sime-config.el#L153-L168 (actually if anybody knows of a more efficient way= to load the file, I'd be keen to update our code, I'm a maintainer). The exact file that it is apparently performing the re_search within is htt= ps://gist.github.com/fommil/d906918819cd2632e9864842e1d59b57 Could anybody please shed some light on what could be going wrong? I also h= ave a core dump file but I have no idea what to do with it, I've never used= gdb in anger. Almost certainly an ArchLinux system update occurred somewhere around the t= ime that this happened. Emacs is the only app that suffers and I get exactl= y the same behaviour on my laptop, so I'm ruling out a memory defect. This is almost certainly a problem with my OS... is anybody else seeing thi= s? I may crosspost on ArchLinux and reference back here. Best regards, Sam