From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757172AbZD2HD3 (ORCPT ); Wed, 29 Apr 2009 03:03:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756137AbZD2HDS (ORCPT ); Wed, 29 Apr 2009 03:03:18 -0400 Received: from cantor2.suse.de ([195.135.220.15]:37026 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756206AbZD2HDR (ORCPT ); Wed, 29 Apr 2009 03:03:17 -0400 Date: Wed, 29 Apr 2009 09:03:16 +0200 From: Nick Piggin To: Valdis.Kletnieks@vt.edu Cc: Andrew Morton , linux-kernel@vger.kernel.org, mm-commits@vger.kernel.org Subject: Re: mmotm 2009-04-24-18-14 uploaded - NVidia indigestion Message-ID: <20090429070316.GA3398@wotan.suse.de> References: <200904250133.n3P1XBJn006790@imap1.linux-foundation.org> <5622.1240628800@turing-police.cc.vt.edu> <20090425052434.GE10088@wotan.suse.de> <57773.1240857915@turing-police.cc.vt.edu> <20090428061557.GA29299@wotan.suse.de> <20954.1240934481@turing-police.cc.vt.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20954.1240934481@turing-police.cc.vt.edu> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 28, 2009 at 12:01:21PM -0400, Valdis.Kletnieks@vt.edu wrote: > On Tue, 28 Apr 2009 08:15:57 +0200, Nick Piggin said: > > Here's the code (pretty much *all* the code): > > > #include > > #include > > int main() { > > if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)) { > > return 0; > > } else { > > return 1; > > } > > } > > > Hmm, yes if you build without -O, then it appears like the compiler > > trips over this. I wouldn't be unhappy with just removing the BUILD_BUG_ON, > > but shouldn't the module be using -O[s2]? > > It's a little autoconfig chunk from vendor code that determines if we're > building on a sane/recent kernel. Not the sort of thing you'd expect to > need to invoke the frikking optimizer for program *correctness* :) The kernel I think has for a long time required -O to compile correctly because some things marked inline have had to be inlined for correctness. This might have changed now that we have __always_inline, but anyway. But I'll just get rid of that BUILD_BUG_ON. Thanks, Nick