Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754688Ab2BSSMd (ORCPT ); Sun, 19 Feb 2012 13:12:33 -0500 Received: from oproxy9.bluehost.com ([69.89.24.6]:33826 "HELO oproxy9.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754541Ab2BSSMb (ORCPT ); Sun, 19 Feb 2012 13:12:31 -0500 Message-ID: <4F413B8D.5080307@xenotime.net> Date: Sun, 19 Feb 2012 10:12:29 -0800 From: Randy Dunlap User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110323 Thunderbird/3.1.9 MIME-Version: 1.0 To: Geert Uytterhoeven CC: Andrew Morton , Konstantin Khlebnikov , Stephen Rothwell , linux-next@vger.kernel.org, LKML , Sam Ravnborg , Michal Marek , linux-kbuild@vger.kernel.org Subject: Re: [PATCH] mm: add config NUMA stub to all architectures References: <4F3E42E0.4030108@openvz.org> <20120217120815.25909.15632.stgit@zurg> <20120217123037.ecfc5dd9.akpm@linux-foundation.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Identified-User: {1807:box742.bluehost.com:xenotime:xenotime.net} {sentby:smtp auth 50.53.38.135 authed with rdunlap@xenotime.net} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1224 Lines: 31 On 02/19/2012 09:01 AM, Geert Uytterhoeven wrote: > On Fri, Feb 17, 2012 at 21:30, Andrew Morton wrote: >> On Fri, 17 Feb 2012 16:08:15 +0400 >> Konstantin Khlebnikov wrote: >> >>> Config NUMA must be defined for all architectures, >>> otherwise IS_ENABLED(CONFIG_NUMA) does not work. >>> Some arch-specific Kconfig already has this stub. >>> This patch adds it to all remaining. >> >> It would be better to teach IS_ENABLED() to handle this situation. I >> don't think there's a way of doing this with cpp :( >> >> This limitation makes IS_ENABLED pretty dangerous, doesn't it? It >> makes it very easy to introduce build breakage with unexpected Kconfig >> combinations. > > Indeed. Recently I discovered IS_ENABLED() and started recommending it > to people for new code. But now I've seen the CONFIG_NUMA breakage, > I no longer think this is a good recommendation. adding Michal & linux-kbuild to cc: list. -- ~Randy -- 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/