From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Lars Ingebrigtsen Newsgroups: gmane.emacs.bugs Subject: bug#54501: Segfault on recursive structure Date: Tue, 22 Mar 2022 15:44:43 +0100 Message-ID: <87cziekpwk.fsf@gnus.org> References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="30223"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: 54501@debbugs.gnu.org, Stefan Monnier To: Andy Gaynor Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Tue Mar 22 15:45:16 2022 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 1nWfl6-0007dM-Fh for geb-bug-gnu-emacs@m.gmane-mx.org; Tue, 22 Mar 2022 15:45:16 +0100 Original-Received: from localhost ([::1]:47924 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nWfl5-00087L-G0 for geb-bug-gnu-emacs@m.gmane-mx.org; Tue, 22 Mar 2022 10:45:15 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:50998) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nWfks-00085W-RM for bug-gnu-emacs@gnu.org; Tue, 22 Mar 2022 10:45:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:47697) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1nWfks-0000te-HO for bug-gnu-emacs@gnu.org; Tue, 22 Mar 2022 10:45:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1nWfks-0003Yc-DZ for bug-gnu-emacs@gnu.org; Tue, 22 Mar 2022 10:45:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Lars Ingebrigtsen Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 22 Mar 2022 14:45:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 54501 X-GNU-PR-Package: emacs Original-Received: via spool by 54501-submit@debbugs.gnu.org id=B54501.164796029613651 (code B ref 54501); Tue, 22 Mar 2022 14:45:02 +0000 Original-Received: (at 54501) by debbugs.gnu.org; 22 Mar 2022 14:44:56 +0000 Original-Received: from localhost ([127.0.0.1]:41594 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1nWfkm-0003Y7-4C for submit@debbugs.gnu.org; Tue, 22 Mar 2022 10:44:56 -0400 Original-Received: from quimby.gnus.org ([95.216.78.240]:34954) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1nWfkk-0003Xq-9z for 54501@debbugs.gnu.org; Tue, 22 Mar 2022 10:44:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnus.org; s=20200322; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=ftmYqw2xDAAg+FHePZRY8J98L9lo1ZVOhlQGX2207sI=; b=igxCoPAu+ggn54/kcSNM1L6C7w vX6l0OOeAcm3TTo6cPDSgrbvuQRNszTiGuHYf/+6vJeXj8AClUgpQVJ/kvuyjVs394SK9sZoEDLlE nDoJZbGSenmbVRjrKYjz5AgnhsRSnoDreFxgCZnayk3C9g2jua3TnOXkriHpHNLsHpwg=; Original-Received: from 109.179.236.69.tmi.telenormobil.no ([109.179.236.69] helo=xo) by quimby.gnus.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nWfka-0006wm-Kp; Tue, 22 Mar 2022 15:44:46 +0100 In-Reply-To: (Andy Gaynor's message of "Mon, 21 Mar 2022 15:26:02 +0100") 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:228762 Archived-At: So this bug report is about two things. The first is that this reads to (nil): #0=#0# Which seems odd. Reading #0=#1# signals an error, but it's not immediately clear to me whether #0=#0# is totally nonsensical or not. And if not, is (nil) the right result? Anybody? The other thing is more serious, and reading the following will segfault your Emacs, so don't do that: #0=[#1=(#0# . #1#)] Now, Emacs segfaults on trying to gc a number of recursive objects (especially ones that recurse in the `car'), but this seems to actually segfault in the reader. Is it obvious to anybody why? -- (domestic pets only, the antidote for overdose, milk.) bloggy blog: http://lars.ingebrigtsen.no