From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20560 invoked by alias); 16 Feb 2007 14:01:43 -0000 Received: (qmail 20536 invoked by uid 22791); 16 Feb 2007 14:01:42 -0000 X-Spam-Check-By: sourceware.org Received: from w099.z064220152.sjc-ca.dsl.cnc.net (HELO bluesmobile.specifix.com) (64.220.152.99) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 16 Feb 2007 14:01:36 +0000 Received: from fishpond.diveadx.com (bluesmobile.corp.specifix.com [192.168.1.32]) by bluesmobile.specifix.com (Postfix) with ESMTP id D7DF43B89B; Fri, 16 Feb 2007 06:01:33 -0800 (PST) From: Fred Fish Reply-To: fnf@specifix.com To: Mark Kettenis Subject: Re: [PATCH] Fix PPC scan_prologue for code generated with -mno-update Date: Fri, 16 Feb 2007 14:01:00 -0000 User-Agent: KMail/1.9.6 Cc: gdb-patches@sources.redhat.com References: <200702151807.06227.fnf@specifix.com> <200702160822.l1G8MYL8026770@brahms.sibelius.xs4all.nl> In-Reply-To: <200702160822.l1G8MYL8026770@brahms.sibelius.xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200702160701.30925.fnf@specifix.com> 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: 2007-02/txt/msg00204.txt.bz2 On Friday 16 February 2007, Mark Kettenis wrote: > Looks reasonable to me. However there's one thing I don't understand. > Presuming you're using DWARF2 debug info, why does improving the > prologue scanner make such a big difference? Good question. Originally the problem popped up in an environment where the user was using stabs debugging format with a pretty ancient compiler. I distilled the problem down to a simple test case and compiled it without debugging info, after I figured out the problem was an issue with the prologue scanner. Perhaps this has uncovered another bug related to how the DWARF info is used. It's certainly worth investigating. However I believe the patch is still beneficial, for the cases where the debug format is something other than DWARF or there is no debug info. -Fred