From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Richard M. Stallman" Newsgroups: gmane.emacs.devel Subject: Re: Crash on invalid cons_free_list Date: Wed, 14 Sep 2005 10:06:36 -0400 Message-ID: References: <87k6hl6o7h.fsf@stupidchicken.com> Reply-To: rms@gnu.org NNTP-Posting-Host: main.gmane.org Content-Type: text/plain; charset=ISO-8859-15 X-Trace: sea.gmane.org 1126709714 27104 80.91.229.2 (14 Sep 2005 14:55:14 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Wed, 14 Sep 2005 14:55:14 +0000 (UTC) Cc: cyd@stupidchicken.com, emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Sep 14 16:55:06 2005 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1EFYcd-0007ie-Vz for ged-emacs-devel@m.gmane.org; Wed, 14 Sep 2005 16:52:28 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1EFYcd-0001ve-Ba for ged-emacs-devel@m.gmane.org; Wed, 14 Sep 2005 10:52:27 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1EFYQz-0005E7-6o for emacs-devel@gnu.org; Wed, 14 Sep 2005 10:40:25 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1EFYQy-0005DY-6S for emacs-devel@gnu.org; Wed, 14 Sep 2005 10:40:24 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1EFYNl-0003hc-Gh for emacs-devel@gnu.org; Wed, 14 Sep 2005 10:37:05 -0400 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.34) id 1EFXuH-000113-Ce for emacs-devel@gnu.org; Wed, 14 Sep 2005 10:06:37 -0400 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.34) id 1EFXuG-0004rE-5h; Wed, 14 Sep 2005 10:06:36 -0400 Original-To: storm@cua.dk (Kim F. Storm) In-reply-to: (storm@cua.dk) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:42922 Archived-At: It seems that most of the crashes triggered by VM are somehow related to mapcar -- and in this case a mapcar called inside mapatoms. The crash happens when cons encounters invalid data in the free list. However, the bug occurred earlier, when the data became invalid. There is no evidence that it is directly related to this mapcar, or to this mapatoms. But if we look at which part of VM does this mapatoms, then depending on how often it is done, it might offer some sort of clue. If VM does this mapatoms very often, perhaps all we can deduce is that most of VM's consing is there, so if the bug happens in VM, it would tend to show up there. That doesn't really help. However, if only a particular VM command does this mapatoms, and most of VM's consing is done elsewhere, maybe it means the bug is in something done by that command. (Not necessarily WITHIN the mapatoms--it could be earlier in the same command.) That could narrow things down to the point where it would be worth rechecking the C code for any unusual thing done by that command.