From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28280 invoked by alias); 8 Nov 2007 20:14:04 -0000 Received: (qmail 28255 invoked by uid 22791); 8 Nov 2007 20:14:03 -0000 X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 08 Nov 2007 20:13:59 +0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.1) with ESMTP id lA8KBrli020292; Thu, 8 Nov 2007 15:11:53 -0500 Received: from pobox.corp.redhat.com (pobox.corp.redhat.com [10.11.255.20]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id lA8KBq3Z022143; Thu, 8 Nov 2007 15:11:53 -0500 Received: from free.oliva.athome.lsd.ic.unicamp.br (vpn-15-91.rdu.redhat.com [10.11.15.91]) by pobox.corp.redhat.com (8.13.1/8.13.1) with ESMTP id lA8KBonV020196; Thu, 8 Nov 2007 15:11:51 -0500 Received: from free.oliva.athome.lsd.ic.unicamp.br (localhost.localdomain [127.0.0.1]) by free.oliva.athome.lsd.ic.unicamp.br (8.14.1/8.14.1) with ESMTP id lA8KBnTB014605; Thu, 8 Nov 2007 18:11:50 -0200 Received: (from aoliva@localhost) by free.oliva.athome.lsd.ic.unicamp.br (8.14.1/8.14.1/Submit) id lA8KBmQ5014604; Thu, 8 Nov 2007 18:11:48 -0200 To: "Andrew Pinski" Cc: "David Edelsohn" , "Mark Mitchell" , "Ian Lance Taylor" , "Richard Guenther" , gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org Subject: Re: Designs for better debug info in GCC References: <84fc9c000711050327x74845c78ya18a3329fcf9e4d2@mail.gmail.com> <4732519C.6070802@codesourcery.com> <200711080014.lA80EEiA028452@makai.watson.ibm.com> From: Alexandre Oliva Errors-To: aoliva@oliva.athome.lsd.ic.unicamp.br Date: Fri, 09 Nov 2007 01:11:00 -0000 In-Reply-To: (Andrew Pinski's message of "Thu\, 8 Nov 2007 11\:12\:52 -0800") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2007-11/txt/msg00260.txt.bz2 On Nov 8, 2007, "Andrew Pinski" wrote: > On 11/7/07, Alexandre Oliva wrote: >> I'm personally getting numerous requests for debug information >> correctness and better completeness from debug info consumers such as >> gdb, frysk and systemtap. GCC's eagerness to inline functions, even >> ones never declared as inline, and its eagerness to corrupt the >> meta-information associated with them, causes these tools to >> malfunction in very many situations. And it's all GCC's fault, for >> generating code that is not standards-compliant in the >> meta-information sections of its output. > I have to ask, do you want an optimizing compiler or one which > generates full debugging information???? I want both. That's the whole point of this project I'm in. > Because there are trade off here really. For a superficial look at the problem, they might look like trade-offs. But the assumption that it's impossible to get both is incorrect. It takes work, but it's not impossible. > The reason behind the extra inlining is because it > improves code generation. I don't see how you got the impression that I might be arguing against the inlining, as it looks like you did. I'm not. I'm arguing against the corruption of meta-information associated with them. That's just laziness on our part. > Remember dwarf3 is not really a standards about meta-information, it > just mentions how it represented if it exists. That's what meta-information is. One of the problems is that we often fail to represent information that does exist. A more serious problem is that we often represent such information incorrectly, making it seem like things that don't exist do, and that things are at different locations from those in which they actually are. -- Alexandre Oliva http://www.lsd.ic.unicamp.br/~oliva/ FSF Latin America Board Member http://www.fsfla.org/ Red Hat Compiler Engineer aoliva@{redhat.com, gcc.gnu.org} Free Software Evangelist oliva@{lsd.ic.unicamp.br, gnu.org}