From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 23438 invoked by alias); 8 Nov 2007 15:13:50 -0000 Received: (qmail 23417 invoked by uid 22791); 8 Nov 2007 15:13:49 -0000 X-Spam-Check-By: sourceware.org Received: from qmta05.westchester.pa.mail.comcast.net (HELO QMTA05.westchester.pa.mail.comcast.net) (76.96.62.48) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 08 Nov 2007 15:13:46 +0000 Received: from OMTA09.westchester.pa.mail.comcast.net ([76.96.62.20]) by QMTA05.westchester.pa.mail.comcast.net with smtp id AEg81Y0070SCNGk0003U00; Thu, 08 Nov 2007 15:13:43 +0000 Received: from lucon.org ([24.6.230.138]) by OMTA09.westchester.pa.mail.comcast.net with comcast id AFDi1Y0042zoa480000000; Thu, 08 Nov 2007 15:13:43 +0000 X-Authority-Analysis: v=1.0 c=1 a=zbuCykIsxmEryw1ZXeoA:9 a=IGtFuVkCJLUy2Fpf2PMSUUTC0YcA:4 a=LY0hPdMaydYA:10 Received: by lucon.org (Postfix, from userid 500) id 01C3BF8275; Thu, 8 Nov 2007 07:13:41 -0800 (PST) Date: Thu, 08 Nov 2007 15:13:00 -0000 From: "H.J. Lu" To: Robert Dewar Cc: Michael Matz , Alexandre Oliva , Richard Guenther , gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org Subject: Re: Designs for better debug info in GCC Message-ID: <20071108151341.GA5561@lucon.org> References: <84fc9c000711050327x74845c78ya18a3329fcf9e4d2@mail.gmail.com> <47331636.9010308@adacore.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47331636.9010308@adacore.com> User-Agent: Mutt/1.5.14 (2007-02-12) X-IsSubscribed: yes Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org X-SW-Source: 2007-11/txt/msg00423.txt.bz2 On Thu, Nov 08, 2007 at 08:59:18AM -0500, Robert Dewar wrote: > 2. It is much more important to have reasonable debugging > for most users than the last mile of optimization. For me > we should ensure that -O1 is still reasonably debuggable. > The switch to GCC 4, at least in the Ada context, has > significantly degraded -O1 debugging. I have found for > instance that debugging the GNAT compiler itself, -O1 > used to be perfectly fine, but now far too many arguments > and variables disappear. > With gcc 3.4, I can debug binutils at -O1 and -O2 in some cases. But with gcc 4, I have to use -O0 if I want to do any serious debug on binutils. H.J.