From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: valgrind emacs Date: Mon, 24 Mar 2008 14:50:31 -0400 Message-ID: References: NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1206384657 9110 80.91.229.12 (24 Mar 2008 18:50:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 24 Mar 2008 18:50:57 +0000 (UTC) Cc: emacs-devel@gnu.org To: Neal Becker Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Mar 24 19:51:27 2008 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1JdrlM-0006Kt-OH for ged-emacs-devel@m.gmane.org; Mon, 24 Mar 2008 19:51:17 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Jdrkl-0007HZ-RT for ged-emacs-devel@m.gmane.org; Mon, 24 Mar 2008 14:50:39 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Jdrkh-0007HT-JS for emacs-devel@gnu.org; Mon, 24 Mar 2008 14:50:35 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Jdrkf-0007HH-4t for emacs-devel@gnu.org; Mon, 24 Mar 2008 14:50:34 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Jdrkf-0007HE-27 for emacs-devel@gnu.org; Mon, 24 Mar 2008 14:50:33 -0400 Original-Received: from ironport2-out.pppoe.ca ([206.248.154.182] helo=ironport2-out.teksavvy.com) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Jdrke-0007IL-U1 for emacs-devel@gnu.org; Mon, 24 Mar 2008 14:50:33 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Aj8FAHqU50dMCrTo/2dsb2JhbACBW6Yz X-IronPort-AV: E=Sophos;i="4.25,547,1199682000"; d="scan'208";a="16541421" Original-Received: from smtp.pppoe.ca (HELO smtp.teksavvy.com) ([65.39.196.238]) by ironport2-out.teksavvy.com with ESMTP; 24 Mar 2008 14:50:32 -0400 Original-Received: from pastel.home ([76.10.180.232]) by smtp.teksavvy.com (Internet Mail Server v1.0) with ESMTP id EVW06232; Mon, 24 Mar 2008 14:50:32 -0400 Original-Received: by pastel.home (Postfix, from userid 20848) id B42CE8069; Mon, 24 Mar 2008 14:50:31 -0400 (EDT) In-Reply-To: (Neal Becker's message of "Sat, 22 Mar 2008 18:31:13 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.60 (gnu/linux) X-detected-kernel: by monty-python.gnu.org: Genre and OS details not recognized. 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:93314 Archived-At: > ==3816== Conditional jump or move depends on uninitialised value(s) > ==3816== at 0x4D68E5: Fgarbage_collect (alloc.c:5004) > ==3816== by 0x4EB922: Feval (eval.c:2248) > ==3816== by 0x5047BB: readevalloop (lread.c:1791) > ==3816== by 0x50614D: Fload (lread.c:1255) > ==3816== by 0x4EBB5E: Feval (eval.c:2370) > ==3816== by 0x5047BB: readevalloop (lread.c:1791) > ==3816== by 0x50614D: Fload (lread.c:1255) > ==3816== by 0x4EBB5E: Feval (eval.c:2370) > ==3816== by 0x4EAC36: internal_condition_case (eval.c:1494) > ==3816== by 0x4856A9: top_level_1 (keyboard.c:1387) > ==3816== by 0x4EAD26: internal_catch (eval.c:1230) > ==3816== by 0x48616E: command_loop (keyboard.c:1342) No idea what this is about. Might be an actual bug. > ==3816== Conditional jump or move depends on uninitialised value(s) > ==3816== at 0x4D2A17: mem_find (alloc.c:3510) > ==3816== by 0x4D36F4: mark_maybe_object (alloc.c:4108) > ==3816== by 0x4D392D: mark_stack (alloc.c:4272) > ==3816== by 0x4D6A55: Fgarbage_collect (alloc.c:5092) > ==3816== by 0x4EB922: Feval (eval.c:2248) > ==3816== by 0x5047BB: readevalloop (lread.c:1791) > ==3816== by 0x50614D: Fload (lread.c:1255) > ==3816== by 0x4EBB5E: Feval (eval.c:2370) > ==3816== by 0x5047BB: readevalloop (lread.c:1791) > ==3816== by 0x50614D: Fload (lread.c:1255) > ==3816== by 0x4EBB5E: Feval (eval.c:2370) > ==3816== by 0x4EAC36: internal_condition_case (eval.c:1494) Most likely a non-issue: the conservative stack-scanning will look at all slots in the stack, and of course some of those may not have been initialized. But the arbitrary values read off the stack are sanity-checked so that they're ignored unless they do correspond to valid Lisp pointers. Maybe they're not really Lisp pointers, so the behavior may be affected by the uninitialized value, but the only effect it should have is to prevent garbage collection of some Lisp objects, i.e. increase the memory footprint. Stefan