From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9014 invoked by alias); 9 Jan 2008 19:44:49 -0000 Received: (qmail 9005 invoked by uid 22791); 9 Jan 2008 19:44:48 -0000 X-Spam-Check-By: sourceware.org Received: from rock.gnat.com (HELO rock.gnat.com) (205.232.38.15) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 09 Jan 2008 19:44:31 +0000 Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id E979F2A96BB; Wed, 9 Jan 2008 14:44:29 -0500 (EST) Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id uZQAbU1BuXEj; Wed, 9 Jan 2008 14:44:29 -0500 (EST) Received: from joel.gnat.com (localhost.localdomain [127.0.0.1]) by rock.gnat.com (Postfix) with ESMTP id 20F782A96B1; Wed, 9 Jan 2008 14:44:29 -0500 (EST) Received: by joel.gnat.com (Postfix, from userid 1000) id BA05BE7ACB; Wed, 9 Jan 2008 11:44:21 -0800 (PST) Date: Wed, 09 Jan 2008 19:44:00 -0000 From: Joel Brobecker To: Jim Blandy Cc: gdb-patches@sourceware.org Subject: Re: [RFC/RFA?] Should break FILE:LINENO skip prologue? Message-ID: <20080109194421.GE21281@adacore.com> References: <20080109151745.GA13181@adacore.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2008-01/txt/msg00212.txt.bz2 > I don't remember the original conversation, but the suggestion still > sounds like a good idea to me. (Whew!) Cool! (double whew ;-) > > [1]: I think we have made some progress with parameter/variable > > tracking with DWARF, but I think it's not activated by default > > and we also still support platforms where DWARF is not available. > > What is "not activated by default", exactly? Is it in GCC? In GDB? > Where in GDB? I think it's in GCC. I am not a GCC expert, so I might be wrong, but I think that the option is -fvar-tracking. Eric Botcazou told me about this option when debugging at -O1 or -O2, but apparently, it has some drawbacks (for now, at least). IIUC, it had to do with the fact that the optimizers have do so much work that it's hard to relate back to the original source code entity. > I've long had this dream that eventually we would just stop skipping > prologues altogether, because everything would actually work at every > instruction in the function. Me too, but I think we're still quite a long ways away from this happening. There is also the case of stabs, that is still, despite a lot of effort from many people (including AdaCore), not extinct. -- Joel