Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758702Ab0KOWn1 (ORCPT ); Mon, 15 Nov 2010 17:43:27 -0500 Received: from one.firstfloor.org ([213.235.205.2]:37756 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754280Ab0KOWn0 (ORCPT ); Mon, 15 Nov 2010 17:43:26 -0500 Date: Mon, 15 Nov 2010 23:43:22 +0100 From: Andi Kleen To: Jakub Jelinek Cc: Linus Torvalds , Jim Bos , Andi Kleen , James Cloos , Linux Kernel Mailing List , Andreas Schwab , Michael Matz , Dave Korn , Richard Guenther , gcc@gcc.gnu.org Subject: Re: gcc 4.5.1 / as 2.20.51.0.11 miscompiling drivers/char/i8k.c ? Message-ID: <20101115224322.GA1303@one.firstfloor.org> References: <20101115105446.GD7269@basil.fritz.box> <20101115111642.GU29412@tyan-ft48-01.lab.bos.redhat.com> <4CE17098.8090000@xs4all.nl> <4CE17C4B.1070305@xs4all.nl> <20101115185848.GI2583@sunsite.ms.mff.cuni.cz> <20101115191248.GY29412@tyan-ft48-01.lab.bos.redhat.com> <20101115195115.GZ29412@tyan-ft48-01.lab.bos.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101115195115.GZ29412@tyan-ft48-01.lab.bos.redhat.com> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 700 Lines: 15 > testcase shows that in 4.1/4.2/4.3/4.4 this is miscompiled only when using > -fno-ipa-reference, in 4.5 it is miscompiled always when optimizing > unless -fno-ipa-pure-const (as 4.5 added local-pure-const pass which is run > before ipa-reference) and in 4.6 this has been fixed by Honza when > doing ipa cleanups. Maybe it would be better to simply change the kernel Makefiles to pass -fno-ipa-pure-const instead of adding volatiles everywhere. -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/