From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Rob Browning Newsgroups: gmane.emacs.bugs Subject: bug#11913: Unusual Emacs 24.1 arithmetic error (abs) on i386 machine Date: Sat, 14 Jul 2012 16:45:33 -0500 Message-ID: <87ehoeqao2.fsf@trouble.defaultvalue.org> References: <87wr2a5gm2.fsf@trouble.defaultvalue.org> <87a9z6ge3i.fsf@trouble.defaultvalue.org> <87fw8v5zab.fsf@trouble.defaultvalue.org> <83hatba4j1.fsf@gnu.org> <3b8venqy86.fsf@fencepost.gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1342302391 24359 80.91.229.3 (14 Jul 2012 21:46:31 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sat, 14 Jul 2012 21:46:31 +0000 (UTC) Cc: 11913@debbugs.gnu.org To: Glenn Morris Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sat Jul 14 23:46:31 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 1SqAAR-000812-Uw for geb-bug-gnu-emacs@m.gmane.org; Sat, 14 Jul 2012 23:46:24 +0200 Original-Received: from localhost ([::1]:47258 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SqAAQ-0004OK-PY for geb-bug-gnu-emacs@m.gmane.org; Sat, 14 Jul 2012 17:46:22 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:51050) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SqAAN-0004MX-C2 for bug-gnu-emacs@gnu.org; Sat, 14 Jul 2012 17:46:20 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SqAAM-0002q1-A7 for bug-gnu-emacs@gnu.org; Sat, 14 Jul 2012 17:46:19 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:60167) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SqAAM-0002ph-7K for bug-gnu-emacs@gnu.org; Sat, 14 Jul 2012 17:46:18 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.72) (envelope-from ) id 1SqAFu-0004bD-9I for bug-gnu-emacs@gnu.org; Sat, 14 Jul 2012 17:52:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Rob Browning Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 14 Jul 2012 21:52:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 11913 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 11913-submit@debbugs.gnu.org id=B11913.134230268317628 (code B ref 11913); Sat, 14 Jul 2012 21:52:02 +0000 Original-Received: (at 11913) by debbugs.gnu.org; 14 Jul 2012 21:51:23 +0000 Original-Received: from localhost ([127.0.0.1]:41480 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1SqAFH-0004aG-AD for submit@debbugs.gnu.org; Sat, 14 Jul 2012 17:51:23 -0400 Original-Received: from defaultvalue.org ([70.85.129.156]:58145) by debbugs.gnu.org with esmtp (Exim 4.72) (envelope-from ) id 1SqAFF-0004a9-GL for 11913@debbugs.gnu.org; Sat, 14 Jul 2012 17:51:22 -0400 Original-Received: from trouble.defaultvalue.org (localhost [127.0.0.1]) (Authenticated sender: rlb@defaultvalue.org) by defaultvalue.org (Postfix) with ESMTPSA id 87A6590D35; Sat, 14 Jul 2012 16:48:08 -0500 (CDT) Original-Received: by trouble.defaultvalue.org (Postfix, from userid 1000) id BD42114E0C1; Sat, 14 Jul 2012 16:45:33 -0500 (CDT) In-Reply-To: <3b8venqy86.fsf@fencepost.gnu.org> (Glenn Morris's message of "Fri, 13 Jul 2012 15:04:25 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1 (gnu/linux) 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:61945 Archived-At: Glenn Morris writes: > But why does (abs 8.0) return an arithmetic error at all...? OK, at the moment, I believe the short answer is because fabs() is changing errno which triggers the default clause in IN_FLOAT() here: default: arith_error (float_error_fn_name, float_error_arg); I've been told that this should be considered an Emacs bug because the effect of fabs() on errno is strictly undefined, and so fabs() is within its rights to do whatever it wants to the value. Hope this helps. -- Rob Browning rlb @defaultvalue.org and @debian.org GPG as of 2002-11-03 14DD 432F AE39 534D B592 F9A0 25C8 D377 8C7E 73A4