From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758695AbYEPVgT (ORCPT ); Fri, 16 May 2008 17:36:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753876AbYEPVgL (ORCPT ); Fri, 16 May 2008 17:36:11 -0400 Received: from terminus.zytor.com ([198.137.202.10]:44488 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751839AbYEPVgK (ORCPT ); Fri, 16 May 2008 17:36:10 -0400 Message-ID: <482DFD65.10300@zytor.com> Date: Fri, 16 May 2008 14:32:21 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Mathieu Desnoyers CC: Jeremy Fitzhardinge , Ingo Molnar , Linux Kernel Mailing List Subject: Re: [PATCH] Fix immediate asm constraint for gcc 3 x86_64 References: <482AB6C5.4060604@goop.org> <20080516124811.GC4226@Krystal> In-Reply-To: <20080516124811.GC4226@Krystal> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Mathieu Desnoyers wrote: > > It seems that include/asm-x86/immediate.h in sched-devel.git causes > this. gcc-3.4 does not seem to like the "i" (&name##__imv) constraint. I > have seen no such problem with gcc-4.1. This is weird. It seems that > relaxing the constraint helps fixing this, but it's not clear whether > fixing the code or gcc-3.4 is the correct solution... here is the fix : > > Fix immediate asm constraint for gcc 3 x86_64 > It might make it compile, but it's completely *wrong* for the purpose intended. It permits gcc to present the address in a register, for example, so there is no guarantee that you end up with an immediate. -hpa