From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#41321: 27.0.91; Emacs aborts due to invalid pseudovector objects Date: Fri, 22 May 2020 15:32:42 +0300 Message-ID: <83r1vc2lqt.fsf@gnu.org> References: <83zha8cgpi.fsf@gnu.org> <83r1vibmyj.fsf@gnu.org> <83imgublku.fsf@gnu.org> <831rncjuwf.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="123037"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 41321@debbugs.gnu.org, monnier@iro.umontreal.ca To: Pip Cet Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri May 22 14:33:23 2020 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jc6rb-000Vuc-8D for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 22 May 2020 14:33:23 +0200 Original-Received: from localhost ([::1]:50086 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jc6ra-0000mh-Ad for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 22 May 2020 08:33:22 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:42684) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jc6rG-0000dx-T4 for bug-gnu-emacs@gnu.org; Fri, 22 May 2020 08:33:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:46779) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jc6rG-0003vQ-Jr for bug-gnu-emacs@gnu.org; Fri, 22 May 2020 08:33:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jc6rG-0006lZ-Fc for bug-gnu-emacs@gnu.org; Fri, 22 May 2020 08:33:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 22 May 2020 12:33:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 41321 X-GNU-PR-Package: emacs Original-Received: via spool by 41321-submit@debbugs.gnu.org id=B41321.159015077925999 (code B ref 41321); Fri, 22 May 2020 12:33:02 +0000 Original-Received: (at 41321) by debbugs.gnu.org; 22 May 2020 12:32:59 +0000 Original-Received: from localhost ([127.0.0.1]:58324 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jc6rC-0006lF-L4 for submit@debbugs.gnu.org; Fri, 22 May 2020 08:32:58 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:35214) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jc6qx-0006kN-8Z for 41321@debbugs.gnu.org; Fri, 22 May 2020 08:32:58 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:47257) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jc6qr-0003to-V2; Fri, 22 May 2020 08:32:37 -0400 Original-Received: from [176.228.60.248] (port=2061 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jc6qr-0000yI-Ac; Fri, 22 May 2020 08:32:37 -0400 In-Reply-To: (message from Pip Cet on Fri, 22 May 2020 11:47:03 +0000) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list 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-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:180758 Archived-At: > From: Pip Cet > Date: Fri, 22 May 2020 11:47:03 +0000 > Cc: Stefan Monnier , 41321@debbugs.gnu.org > > On Fri, May 22, 2020 at 7:22 AM Eli Zaretskii wrote: > > (gdb) p current_buffer->overlays_before > > $28 = (struct Lisp_Overlay *) 0x170cb080 > > (gdb) p $28->start > > $29 = XIL(0xa0000000170cb040) > > (gdb) xtype > > Lisp_Vectorlike > > Cannot access memory at address 0x18ac04f8 > > Note that didn't try to print $29, but the original invalid marker. In > particular, I believe 0x170cb040 is a pointer to a valid marker. > > > (gdb) p $28->next > > $30 = (struct Lisp_Overlay *) 0x13050320 > > (gdb) p $28->next->start > > $31 = XIL(0xa000000016172310) > > (gdb) xtype > > Lisp_Vectorlike > > Cannot access memory at address 0x18ac04f8 > > Same here. > > If you could disassemble signal_before_change, we'd know whether > start_marker and end_marker live in callee-saved registers, and thus > whether this is likely to be Andrea's bug. Since $28 is neither start_marker nor end_marker, but the first overlay on the buffer's overlay chain, how could it be affected by whether start_marker or end_marker are in a callee-saved register? What am I missing here?