From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Juri Linkov Newsgroups: gmane.emacs.bugs Subject: bug#5754: Bytecomp Arithmetic test failed Date: Sun, 04 Apr 2010 01:54:50 +0300 Organization: JURTA Message-ID: <878w949lwp.fsf@mail.jurta.org> References: <87iq88ma6c.fsf@stupidchicken.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: dough.gmane.org 1270337211 15818 80.91.229.12 (3 Apr 2010 23:26:51 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Sat, 3 Apr 2010 23:26:51 +0000 (UTC) Cc: 5754@debbugs.gnu.org To: Chong Yidong Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Apr 04 01:26:45 2010 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1NyCjj-0001nW-V2 for geb-bug-gnu-emacs@m.gmane.org; Sun, 04 Apr 2010 01:26:44 +0200 Original-Received: from localhost ([127.0.0.1]:54876 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NyCjj-0001z6-0D for geb-bug-gnu-emacs@m.gmane.org; Sat, 03 Apr 2010 19:26:43 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NyCiz-0001fL-Rc for bug-gnu-emacs@gnu.org; Sat, 03 Apr 2010 19:25:57 -0400 Original-Received: from [140.186.70.92] (port=57421 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NyCiy-0001en-H9 for bug-gnu-emacs@gnu.org; Sat, 03 Apr 2010 19:25:57 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1NyCix-00074h-4B for bug-gnu-emacs@gnu.org; Sat, 03 Apr 2010 19:25:56 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:58472) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1NyCiw-00074X-Gz for bug-gnu-emacs@gnu.org; Sat, 03 Apr 2010 19:25:54 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.69) (envelope-from ) id 1NyCSb-0000tU-L7; Sat, 03 Apr 2010 19:09:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Juri Linkov Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-To: owner@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sat, 03 Apr 2010 23:09:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 5754 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 5754-submit@debbugs.gnu.org id=B5754.12703360833425 (code B ref 5754); Sat, 03 Apr 2010 23:09:01 +0000 Original-Received: (at 5754) by debbugs.gnu.org; 3 Apr 2010 23:08:03 +0000 Original-Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1NyCRf-0000tC-1W for submit@debbugs.gnu.org; Sat, 03 Apr 2010 19:08:03 -0400 Original-Received: from smtp-out2.starman.ee ([85.253.0.4] helo=mx2.starman.ee) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1NyCRd-0000sr-8M for 5754@debbugs.gnu.org; Sat, 03 Apr 2010 19:08:02 -0400 X-Virus-Scanned: by Amavisd-New at mx2.starman.ee Original-Received: from mail.starman.ee (82.131.28.129.cable.starman.ee [82.131.28.129]) by mx2.starman.ee (Postfix) with ESMTP id 321E63F407C; Sun, 4 Apr 2010 02:07:51 +0300 (EEST) In-Reply-To: <87iq88ma6c.fsf@stupidchicken.com> (Chong Yidong's message of "Sat, 03 Apr 2010 18:40:59 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (x86_64-pc-linux-gnu) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Resent-Date: Sat, 03 Apr 2010 19:09:01 -0400 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) 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: , Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:35905 Archived-At: > I originally thought this was a regression, because my copy of Emacs > 23.1 did not appear to have this problem. On further investigation, it > is not a regression. Emacs 23.1 and before also have the problem. > > The key is that if I compile Emacs with CFLAGS="-g", then > > (funcall > (byte-compile > (list 'lambda nil > (quote (let ((a (expt 2 -1074)) (b 0.125)) (* a 8 b)))))) > > returns 0.0. If I compile Emacs with CFLAGS="-g -O2", then it returns > 5e-324. Does (let ((a (expt 2 -1074)) (b 0.125)) (* a b 8)) return 5e-324 when you compile with CFLAGS="-g -O2"? Note the constant 8 at the end, this form is what actually executed after byte-compilation with optimization. I guess if (funcall (byte-compile (list 'lambda nil (quote (let ((a (expt 2 -1074)) (b 0.125)) (* a 8 b)))))) returns 5e-324 with CFLAGS="-g -O2", then (let ((a (expt 2 -1074)) (b 0.125)) (* a b 8)) returns 5e-324 as well? -- Juri Linkov http://www.jurta.org/emacs/