From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Andrea Corallo Newsgroups: gmane.emacs.bugs Subject: bug#41321: 27.0.91; Emacs aborts due to invalid pseudovector objects Date: Sat, 23 May 2020 17:58:19 +0000 Message-ID: References: <83zha8cgpi.fsf@gnu.org> <83r1vibmyj.fsf@gnu.org> <83imgublku.fsf@gnu.org> <831rncjuwf.fsf@gnu.org> <83tv082mm1.fsf@gnu.org> <83lflk2l07.fsf@gnu.org> <83blmg2ggi.fsf@gnu.org> <834ks73i8n.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="57254"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) Cc: 41321@debbugs.gnu.org, Stefan Monnier To: Pip Cet Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Sat May 23 19:59:15 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 1jcYQV-000EoG-Ab for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 23 May 2020 19:59:15 +0200 Original-Received: from localhost ([::1]:36364 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jcYQU-0000l3-As for geb-bug-gnu-emacs@m.gmane-mx.org; Sat, 23 May 2020 13:59:14 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:49134) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jcYQI-0000jy-KM for bug-gnu-emacs@gnu.org; Sat, 23 May 2020 13:59:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:52179) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jcYQI-0004ht-Bc for bug-gnu-emacs@gnu.org; Sat, 23 May 2020 13:59:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jcYQI-00079R-Bi for bug-gnu-emacs@gnu.org; Sat, 23 May 2020 13:59:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Andrea Corallo Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 23 May 2020 17:59:02 +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=B41321.159025670227431 (code B ref 41321); Sat, 23 May 2020 17:59:02 +0000 Original-Received: (at 41321) by debbugs.gnu.org; 23 May 2020 17:58:22 +0000 Original-Received: from localhost ([127.0.0.1]:35487 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jcYPe-00078N-1Z for submit@debbugs.gnu.org; Sat, 23 May 2020 13:58:22 -0400 Original-Received: from mx.sdf.org ([205.166.94.20]:51382) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jcYPc-00078G-RJ for 41321@debbugs.gnu.org; Sat, 23 May 2020 13:58:21 -0400 Original-Received: from sdf.org (ma.sdf.org [205.166.94.33]) by mx.sdf.org (8.15.2/8.14.5) with ESMTPS id 04NHwKDk016404 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits) verified NO); Sat, 23 May 2020 17:58:20 GMT Original-Received: (from akrl@localhost) by sdf.org (8.15.2/8.12.8/Submit) id 04NHwJ44024688; Sat, 23 May 2020 17:58:19 GMT In-Reply-To: (Pip Cet's message of "Sat, 23 May 2020 07:00:56 +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:180832 Archived-At: Pip Cet writes: > I believe this isn't the problem we're looking for, but it might be > related anyway. > > I'm seeing this in the assembler source code for insdel.c produced > with the mingw cross compiler (i686-w64-mingw32-gcc-win32): > > movl 60(%esp), %eax > movl %eax, (%esp) > movl 72(%esp), %eax > movl %eax, 4(%esp) > call _Fmarker_position > If I'm reading this correctly, it's of some concern for wide-int > builds: the two 32-bit halves of a Lisp_Object are stored > non-consecutively. > > Our stack marking doesn't catch that; at least, it doesn't for > symbols, where the less-significant half isn't a valid pointer. For > pseudovectors, things should still work... > > So I think we have a problem with such --wide-int builds in cases > where a stack temporary holds an unpinned uninterned symbol while GC > is called. Something like > > (prog1 > (gensym) > (garbage-collect)) > > might trigger it. No problem with gcc -m32 on GNU/Linux, for some reason. Very interesting. AFAIK there's no guarantees for the compiler to spill a DI reg in adjacent memory. Also reading the GC code your observation seems correct to me. -- akrl@sdf.org