From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Help please! To track down GC trying to free an already freed object. Date: Wed, 03 Apr 2019 07:39:35 +0300 Message-ID: <831s2jg0s8.fsf@gnu.org> References: <20190402112537.GA6212@ACM> <835zrwfc21.fsf@gnu.org> <20190402204653.GC25792@ACM> Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="132524"; mail-complaints-to="usenet@blaine.gmane.org" Cc: dancol@dancol.org, emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Apr 03 06:39:31 2019 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hBXgQ-000YNV-V6 for ged-emacs-devel@m.gmane.org; Wed, 03 Apr 2019 06:39:31 +0200 Original-Received: from localhost ([127.0.0.1]:38972 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hBXgP-0002o1-S5 for ged-emacs-devel@m.gmane.org; Wed, 03 Apr 2019 00:39:29 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:57504) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hBXgJ-0002nk-Ic for emacs-devel@gnu.org; Wed, 03 Apr 2019 00:39:24 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:47699) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hBXgI-00044o-Ic; Wed, 03 Apr 2019 00:39:22 -0400 Original-Received: from [176.228.60.248] (port=4395 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1hBXgH-0000Z0-Jt; Wed, 03 Apr 2019 00:39:22 -0400 In-reply-to: <20190402204653.GC25792@ACM> (message from Alan Mackenzie on Tue, 2 Apr 2019 20:46:53 +0000) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:234910 Archived-At: > Date: Tue, 2 Apr 2019 20:46:53 +0000 > From: Alan Mackenzie > Cc: Daniel Colascione , emacs-devel@gnu.org > > > GDB supports reverse execution as well, on some platforms. > > On my GNU/Linux system, I tried to run 'reverse-next', and got the error > message: > > Target multi-thread does not support this command. I think you are supposed to record the execution, and then say (gdb) target record-core or (gdb) target record-btrace before the reverse execution is available. But I was always able to debug GC problems by using last_marked array.