From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Drew Adams" Newsgroups: gmane.emacs.bugs Subject: bug#12677: 24.2.50; `nreverse' complains that ("foo") is not `listp' Date: Thu, 18 Oct 2012 18:47:23 -0700 Message-ID: <7D8BA66E4D4345B7B791FCBC591A8AF3@us.oracle.com> References: <26A504004FDA4E18B0A20DF23152CC5D@us.oracle.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1350611321 20313 80.91.229.3 (19 Oct 2012 01:48:41 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 19 Oct 2012 01:48:41 +0000 (UTC) Cc: 12677-done@debbugs.gnu.org To: "'Stefan Monnier'" Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Fri Oct 19 03:48:48 2012 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1TP1he-0003SY-Tq for geb-bug-gnu-emacs@m.gmane.org; Fri, 19 Oct 2012 03:48:47 +0200 Original-Received: from localhost ([::1]:48395 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TP1hX-0001CI-TJ for geb-bug-gnu-emacs@m.gmane.org; Thu, 18 Oct 2012 21:48:39 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:36250) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TP1hV-0001BB-1A for bug-gnu-emacs@gnu.org; Thu, 18 Oct 2012 21:48:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TP1hU-0005Xg-0l for bug-gnu-emacs@gnu.org; Thu, 18 Oct 2012 21:48:36 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:40509) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TP1hT-0005Xb-TF for bug-gnu-emacs@gnu.org; Thu, 18 Oct 2012 21:48:35 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.72) (envelope-from ) id 1TP1is-0005JY-CR for bug-gnu-emacs@gnu.org; Thu, 18 Oct 2012 21:50:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: "Drew Adams" Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 19 Oct 2012 01:50:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 12677 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 12677-done@debbugs.gnu.org id=D12677.135061136620383 (code D ref 12677); Fri, 19 Oct 2012 01:50:02 +0000 Original-Received: (at 12677-done) by debbugs.gnu.org; 19 Oct 2012 01:49:26 +0000 Original-Received: from localhost ([127.0.0.1]:50760 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TP1iH-0005Ih-Nh for submit@debbugs.gnu.org; Thu, 18 Oct 2012 21:49:25 -0400 Original-Received: from acsinet15.oracle.com ([141.146.126.227]:46970) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1TP1iF-0005IV-QE for 12677-done@debbugs.gnu.org; Thu, 18 Oct 2012 21:49:24 -0400 Original-Received: from acsinet22.oracle.com (acsinet22.oracle.com [141.146.126.238]) by acsinet15.oracle.com (Sentrion-MTA-4.2.2/Sentrion-MTA-4.2.2) with ESMTP id q9J1ln31019761 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 19 Oct 2012 01:47:50 GMT Original-Received: from acsmt358.oracle.com (acsmt358.oracle.com [141.146.40.158]) by acsinet22.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id q9J1lnJh018781 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 19 Oct 2012 01:47:49 GMT Original-Received: from abhmt119.oracle.com (abhmt119.oracle.com [141.146.116.71]) by acsmt358.oracle.com (8.12.11.20060308/8.12.11) with ESMTP id q9J1lnqX006697; Thu, 18 Oct 2012 20:47:49 -0500 Original-Received: from dradamslap1 (/10.159.186.224) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 18 Oct 2012 18:47:48 -0700 X-Mailer: Microsoft Office Outlook 11 In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 thread-index: Ac2tlHv0vA3EuyDmSxe20VzWHyNe4wABoY0g X-Source-IP: acsinet22.oracle.com [141.146.126.238] X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.13 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) X-Received-From: 140.186.70.43 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.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:65721 Archived-At: > My guess is that the code ended up doing something morally equivalent > to (nreverse '(1 2 . 3)). Try it and you'll see a similarly confusing > error message. I understand your guess, but I think that might not be what was happening. In the debugger I evaluated the variable and saw that its full value was just that singleton list. But I'm OK with your closing this, as I cannot repro it from emacs -Q and it does not interfere with my code. > The reason is that by the time you get to the error, the list has > already been "nreversed" by side-effect, so the arg (which > still points to the cons cell which used to be the first element > of the line) now still points to the same cons-cell, but that > cons-cell's cdr has been set to nil because it was to become the > last element of the returned list. Do I understand correctly that a true list with a single element should not present such a problem? > I've installed a change in trunk which makes the above error > include the problematic non-nil tail, rather than the first > element who looks confusingly normal. Sounds good.