Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761467AbYBRNMV (ORCPT ); Mon, 18 Feb 2008 08:12:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755876AbYBRNMG (ORCPT ); Mon, 18 Feb 2008 08:12:06 -0500 Received: from mx2.suse.de ([195.135.220.15]:33270 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753403AbYBRNME (ORCPT ); Mon, 18 Feb 2008 08:12:04 -0500 To: Arnaldo Carvalho de Melo Cc: Ingo Molnar , linux-kernel@vger.kernel.org, sam@ravnborg.org Subject: Re: Reducing debuginfo size by removing unneeded includes From: Andi Kleen References: <20080207230304.GA4352@ghostprotocols.net> Date: Mon, 18 Feb 2008 14:12:01 +0100 In-Reply-To: <20080207230304.GA4352@ghostprotocols.net> (Arnaldo Carvalho de Melo's message of "Thu\, 7 Feb 2008 21\:03\:04 -0200") 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1654 Lines: 41 Arnaldo Carvalho de Melo writes: > > [acme@doppio net-2.6]$ l /tmp/sys_ia32.o.before /tmp/sys_ia32.o.after > -rw-rw-r-- 1 acme acme 185240 2008-02-06 19:19 /tmp/sys_ia32.o.after > -rw-rw-r-- 1 acme acme 248328 2008-02-06 19:00 /tmp/sys_ia32.o.before > > Almost 64KB only on this object file! Just FYI, newer gcc does this in theory automatically when you specify -feliminate-unused-debug-types -feliminate-unused-debug-symbols But in my tests on gcc 4.1 / gcc 4.2 it doesn't seem to make any difference currently :/ Not sure what is wrong. There is also -feliminate-dwarf2-dups, but it seems to even increase obj dir size. Also -feliminate-dwarf2-dups seems to generate a lot of WARNING: vmlinux.o (.gnu.linkonce.wi.mmzone.h.97561702): unexpected section name. The (.[number]+) following section name are ld generated and not expected. Did you forget to use "ax"/"aw" in a .S file? Note that for example contains section definitions for use in .S files. etc. warnings But the kernel builds fine even with those warnings. Still if you just want to shrink objdir size then figuring out what's wrong with these options and then specifying them would be probably the best strategy than to try to do it all manually. That said removing unused includes is of course a valuable clean up by itself, I'm just not sure it's the best way to get smaller object dirs. -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/