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#33014: 26.1.50; 27.0.50; Fatal error after re-evaluating a thread's function Date: Wed, 31 Oct 2018 17:33:56 +0200 Message-ID: <835zxijfkr.fsf@gnu.org> References: <2c81bff7-6376-0bfb-20af-c1fe50a0c313@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org X-Trace: blaine.gmane.org 1540999993 16602 195.159.176.226 (31 Oct 2018 15:33:13 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 31 Oct 2018 15:33:13 +0000 (UTC) Cc: gazally@runbox.com, 33014@debbugs.gnu.org, schwab@linux-m68k.org, monnier@iro.umontreal.ca To: Paul Eggert Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Oct 31 16:33:09 2018 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 1gHsUW-0004DE-Lp for geb-bug-gnu-emacs@m.gmane.org; Wed, 31 Oct 2018 16:33:08 +0100 Original-Received: from localhost ([::1]:60233 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gHsWd-00016A-6M for geb-bug-gnu-emacs@m.gmane.org; Wed, 31 Oct 2018 11:35:19 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55783) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gHsWR-00014u-UJ for bug-gnu-emacs@gnu.org; Wed, 31 Oct 2018 11:35:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gHsWO-0008Ue-0L for bug-gnu-emacs@gnu.org; Wed, 31 Oct 2018 11:35:07 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:53137) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gHsWM-0008Sx-An for bug-gnu-emacs@gnu.org; Wed, 31 Oct 2018 11:35:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1gHsWM-0003WS-4C for bug-gnu-emacs@gnu.org; Wed, 31 Oct 2018 11:35:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 31 Oct 2018 15:35:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 33014 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: fixed Original-Received: via spool by 33014-submit@debbugs.gnu.org id=B33014.154100008413511 (code B ref 33014); Wed, 31 Oct 2018 15:35:02 +0000 Original-Received: (at 33014) by debbugs.gnu.org; 31 Oct 2018 15:34:44 +0000 Original-Received: from localhost ([127.0.0.1]:57395 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gHsW0-0003Vo-9j for submit@debbugs.gnu.org; Wed, 31 Oct 2018 11:34:44 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:45999) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gHsVz-0003Vb-AH for 33014@debbugs.gnu.org; Wed, 31 Oct 2018 11:34:39 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gHsVk-00081I-7E for 33014@debbugs.gnu.org; Wed, 31 Oct 2018 11:34:28 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:36976) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gHsVM-0007he-6N; Wed, 31 Oct 2018 11:34:00 -0400 Original-Received: from [176.228.60.248] (port=3496 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1gHsVL-0002WU-KG; Wed, 31 Oct 2018 11:34:00 -0400 In-reply-to: <2c81bff7-6376-0bfb-20af-c1fe50a0c313@cs.ucla.edu> (message from Paul Eggert on Tue, 30 Oct 2018 21:49:46 -0700) 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:151863 Archived-At: > Cc: Gemini Lasswell , 33014@debbugs.gnu.org, > Stefan Monnier , > Andreas Schwab > From: Paul Eggert > Date: Tue, 30 Oct 2018 21:49:46 -0700 > > > Any reason not to cherry-pick this to emacs-26? > > No, once we fix it up. Although adding 'volatile' happened to work for Gemini's > compiler, it won't suffice in general as the C standard does not require > volatile variables to survive their last access (which is what the patch was > assuming). Furthermore, Fbyte_code bypasses that patch, so the bug could still > occur even if 'volatile' cured the bug in the more-common code path. > > A simple way to ensure that the constant vector survives GC is to have > exec_byte_code put the vector into a GC-visible slot. As it happens, there's a > spare slot that we can appropriate, so this won't cost us stack (or heap) space. > I installed the first attached patch into master to do that, and backported the > patch series into emacs-26 via the last two attached patches. Thanks.