Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752903Ab3IPHYN (ORCPT ); Mon, 16 Sep 2013 03:24:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23038 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062Ab3IPHYM (ORCPT ); Mon, 16 Sep 2013 03:24:12 -0400 Date: Mon, 16 Sep 2013 10:26:03 +0300 From: "Michael S. Tsirkin" To: Stephen Rothwell Cc: Rusty Russell , LKML Subject: Re: Why does test_bit() take a volatile addr? Message-ID: <20130916072603.GA11007@redhat.com> References: <87ioy11k8s.fsf@rustcorp.com.au> <20130916165344.144f0d0f1b58111f1c8c87cc@canb.auug.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130916165344.144f0d0f1b58111f1c8c87cc@canb.auug.org.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 852 Lines: 26 On Mon, Sep 16, 2013 at 04:53:44PM +1000, Stephen Rothwell wrote: > Hi Rusty, > > On Mon, 16 Sep 2013 13:38:35 +0930 Rusty Russell wrote: > > > > Predates git, does anyone remember the rationale? > > > > ie: > > int test_bit(int nr, const volatile unsigned long *addr) > > Because we sometimes pass volatile pointers to it and gcc will complain > if you pass a volatile to a non volatile (I think). Where are these? I did git grep -W test_bit and looked for volatile, couldn't find anything. > -- > Cheers, > Stephen Rothwell sfr@canb.auug.org.au -- 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/