From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Floating-point constant folding in Emacs byte compiler Date: Thu, 22 Mar 2018 21:26:00 -0400 Message-ID: References: <2ce39e5c-cd1b-65d6-b125-719caad67932@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1521768255 9727 195.159.176.226 (23 Mar 2018 01:24:15 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 23 Mar 2018 01:24:15 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Mar 23 02:24:11 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1ezBRD-0002Pr-0V for ged-emacs-devel@m.gmane.org; Fri, 23 Mar 2018 02:24:11 +0100 Original-Received: from localhost ([::1]:35560 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ezBTG-0006ds-Dy for ged-emacs-devel@m.gmane.org; Thu, 22 Mar 2018 21:26:18 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59062) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ezBT9-0006dX-Je for emacs-devel@gnu.org; Thu, 22 Mar 2018 21:26:12 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ezBT6-000892-GC for emacs-devel@gnu.org; Thu, 22 Mar 2018 21:26:11 -0400 Original-Received: from [195.159.176.226] (port=52341 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ezBT6-00086i-8O for emacs-devel@gnu.org; Thu, 22 Mar 2018 21:26:08 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1ezBQz-0002EH-Ua for emacs-devel@gnu.org; Fri, 23 Mar 2018 02:23:57 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 12 Original-X-Complaints-To: usenet@blaine.gmane.org Cancel-Lock: sha1:0yX8JgGnSduXJh94PIVtBSaXj1k= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.159.176.226 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:223930 Archived-At: > These discrepancies mean that .elc files containing floating-point constants > might not be platform-independent, in that byte-compiling a file on one > machine X and running it on another machine Y can yield different results > than byte-compiling and running the same file on Y. Is this sort of > discrepancy intended? I'm pretty sure those runtime differences are not on-purpose, so whether they show up at run-time or compile-time doesn't matter. IOW we can keep optimizing those. Stefan