From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.bugs Subject: bug#17806: 24.4.50; Branch emacs-24 fails to beuild on Debian Date: Tue, 24 Jun 2014 09:27:50 -0700 Organization: UCLA Computer Science Department Message-ID: <53A9A706.70505@cs.ucla.edu> References: <87ionxaloa.fsf@glaurung.internal.golden-gryphon.com> <53A3D1F8.3070306@cs.ucla.edu> <53A99196.3030308@yandex.ru> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1403627366 17269 80.91.229.3 (24 Jun 2014 16:29:26 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 24 Jun 2014 16:29:26 +0000 (UTC) Cc: 17806@debbugs.gnu.org To: Dmitry Antipov Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Jun 24 18:29:20 2014 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 1WzTav-0004Q2-Pq for geb-bug-gnu-emacs@m.gmane.org; Tue, 24 Jun 2014 18:29:17 +0200 Original-Received: from localhost ([::1]:60904 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzTav-0008LE-Ci for geb-bug-gnu-emacs@m.gmane.org; Tue, 24 Jun 2014 12:29:17 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:58730) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzTam-0008Hq-Hc for bug-gnu-emacs@gnu.org; Tue, 24 Jun 2014 12:29:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WzTag-0006Om-IF for bug-gnu-emacs@gnu.org; Tue, 24 Jun 2014 12:29:08 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:40110) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WzTag-0006Oi-FF for bug-gnu-emacs@gnu.org; Tue, 24 Jun 2014 12:29:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WzTaf-0005NC-RE for bug-gnu-emacs@gnu.org; Tue, 24 Jun 2014 12:29:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Paul Eggert Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 24 Jun 2014 16:29:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17806 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 17806-submit@debbugs.gnu.org id=B17806.140362728920538 (code B ref 17806); Tue, 24 Jun 2014 16:29:01 +0000 Original-Received: (at 17806) by debbugs.gnu.org; 24 Jun 2014 16:28:09 +0000 Original-Received: from localhost ([127.0.0.1]:59487 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WzTZo-0005LB-A3 for submit@debbugs.gnu.org; Tue, 24 Jun 2014 12:28:08 -0400 Original-Received: from smtp.cs.ucla.edu ([131.179.128.62]:47044) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WzTZm-0005Kb-32 for 17806@debbugs.gnu.org; Tue, 24 Jun 2014 12:28:06 -0400 Original-Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id 47621A60001; Tue, 24 Jun 2014 09:27:59 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Original-Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3x9qYGxFvw02; Tue, 24 Jun 2014 09:27:54 -0700 (PDT) Original-Received: from [192.168.1.9] (pool-108-0-233-62.lsanca.fios.verizon.net [108.0.233.62]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id 6B7CD39E8019; Tue, 24 Jun 2014 09:27:54 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 In-Reply-To: <53A99196.3030308@yandex.ru> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x 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:90743 Archived-At: Dmitry Antipov wrote: > RedHat's compiler engineer claims that LTO has made substantial progress > in gcc-4.9: http://vmakarov.fedorapeople.org/spec/2014/2014.html Those comments say that GCC 4.9.0 compiles much faster than GCC 4.8.3 when LTO is used. And that's understandable: in 4.9.0, -flto defaults to -fno-fat-lto-objects. Unfortunately, this is the change that broke the Emacs build. Emacs has worked around the problem by compiling with -ffat-lto-objects, but this negates the compile-time performance advantage of 4.9.0. 4.9.0 has not made significant improvements in run-time performance over 4.8.3 when LTO is used, and for Emacs LTO has only minor (and sometimes even negative) run-time performance improvements compared to non-LTO.