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: Sun, 24 May 2020 19:55:29 +0300 Message-ID: <83r1v9w9vi.fsf@gnu.org> References: <83zha8cgpi.fsf@gnu.org> <83r1vibmyj.fsf@gnu.org> <83imgublku.fsf@gnu.org> <831rncjuwf.fsf@gnu.org> <83h7w5xvfa.fsf@gnu.org> <83y2phwb9x.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="83798"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 41321@debbugs.gnu.org, monnier@iro.umontreal.ca To: pipcet@gmail.com Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sun May 24 18:56:13 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 1jctv0-000Lca-0i for geb-bug-gnu-emacs@m.gmane-mx.org; Sun, 24 May 2020 18:56:10 +0200 Original-Received: from localhost ([::1]:36518 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jctuy-0000B2-Lv for geb-bug-gnu-emacs@m.gmane-mx.org; Sun, 24 May 2020 12:56:08 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:54614) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jctus-0000Aa-QF for bug-gnu-emacs@gnu.org; Sun, 24 May 2020 12:56:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:55247) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jctus-0008Ue-H8 for bug-gnu-emacs@gnu.org; Sun, 24 May 2020 12:56:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jctus-0002t5-GZ for bug-gnu-emacs@gnu.org; Sun, 24 May 2020 12:56:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 24 May 2020 16:56:02 +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=B41321.159033933411067 (code B ref 41321); Sun, 24 May 2020 16:56:02 +0000 Original-Received: (at 41321) by debbugs.gnu.org; 24 May 2020 16:55:34 +0000 Original-Received: from localhost ([127.0.0.1]:38560 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jctuQ-0002sR-C5 for submit@debbugs.gnu.org; Sun, 24 May 2020 12:55:34 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:47158) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jctuO-0002sE-QT for 41321@debbugs.gnu.org; Sun, 24 May 2020 12:55:33 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:34503) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jctuJ-0008B1-4L; Sun, 24 May 2020 12:55:27 -0400 Original-Received: from [176.228.60.248] (port=1793 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jctuD-0007VW-EI; Sun, 24 May 2020 12:55:25 -0400 In-Reply-To: <83y2phwb9x.fsf@gnu.org> (message from Eli Zaretskii on Sun, 24 May 2020 19:25:14 +0300) 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:180908 Archived-At: > Date: Sun, 24 May 2020 19:25:14 +0300 > From: Eli Zaretskii > Cc: 41321@debbugs.gnu.org, monnier@iro.umontreal.ca > > > > I still very much doubt that this has anything to do with stack > > > marking during GC, since I've shown in my backtrace that > > > current_buffer->overlays_before points to an overlay with invalid > > > markers. > > > > You haven't. > > Of course, I have. Here's how healthy overlays look in a healthy buffer: (gdb) p current_buffer->overlays_after $10 = (struct Lisp_Overlay *) 0x0 (gdb) p current_buffer->overlays_before $11 = (struct Lisp_Overlay *) 0x7728258 (gdb) p $11->start $12 = XIL(0xa000000007728218) (gdb) xtype Lisp_Vectorlike PVEC_MARKER (gdb) xmarker $13 = (struct Lisp_Marker *) 0x7728218 (gdb) p *$ $14 = { header = { size = 1124081664 }, buffer = 0x728fc38, need_adjustment = 0, insertion_type = 0, next = 0x765eae8, charpos = 13968, bytepos = 13968 } (gdb) p $11->next $15 = (struct Lisp_Overlay *) 0x0 And here's a reminder from how the same looked in the session that segfaulted: (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 (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 (gdb) p current_buffer->overlays_after $32 = (struct Lisp_Overlay *) 0x0 (gdb) p $28->next->next $33 = (struct Lisp_Overlay *) 0x0 If you still claim that I didn't demonstrate that the buffer's overlay chain got corrupted as part of the bug that caused the segfault, please point out what I missed here.