Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756453Ab0GLRkx (ORCPT ); Mon, 12 Jul 2010 13:40:53 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:37854 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756375Ab0GLRkw (ORCPT ); Mon, 12 Jul 2010 13:40:52 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=xkxA0uOU3aFIKhBp8/kybz9vzWHwVgy3f5XV/Rdf+iAg3GowfsxlACR6+c5nedNUHv SdVUUiZwcygii8UvXYccwC1ZjMZDDuExNNZjs103anX7B9FVwjX113FvdU3u7vHL8rrI mHLhVmK3aGmKNOddmXglFyZK2cbrITYZ/y6GQ= MIME-Version: 1.0 In-Reply-To: <20100712172847.GA17423@merkur.ravnborg.org> References: <201007120554.16459.vda.linux@googlemail.com> <20100712100301.db1d3980.randy.dunlap@oracle.com> <20100712172847.GA17423@merkur.ravnborg.org> Date: Mon, 12 Jul 2010 19:40:50 +0200 Message-ID: Subject: Re: Modpost error after changing CONFIG_SOUND from m to y From: Denys Vlasenko To: Sam Ravnborg Cc: Randy Dunlap , Takashi Iwai , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2030 Lines: 55 On Mon, Jul 12, 2010 at 7:28 PM, Sam Ravnborg wrote: > On Mon, Jul 12, 2010 at 07:11:47PM +0200, Denys Vlasenko wrote: >> On Mon, Jul 12, 2010 at 7:03 PM, Randy Dunlap wrote: >> > On Mon, 12 Jul 2010 05:54:16 +0200 Denys Vlasenko wrote: >> >> I was using the same .config for my home machine for a long time, >> >> updating it using "make oldconfig" every time I moved to newer kernel. >> >> It worked fine for many kernels. >> >> >> >> In this .config I had CONFIG_SOUND=m. >> >> >> >> Starting witn 2.6.34, build fails with >> >> >> >> sound/core/sound_oss.c:25:2: error: #error "Enable the OSS soundcore multiplexer (CONFIG_SOUND) in the kernel." >> >> >> >> Ok. I changed CONFIG_SOUND to y. Now the build fails at modpost: >> > >> > Hi, >> > I can't get the build to fail (2.6.34 or 2.6.35-rc4-git4). >> > Please provide a full/complete .config file (and that will include a >> > kernel version number :). >> >> I found out that build only fails if I give empty CFLAGS_KERNEL >> and CFLAGS_MODULE variables to make, like this: >> >> make CFLAGS_KERNEL="" CFLAGS_MODULE="" > > Messing around with kernel internal flags is bound to give > unpredictable bugs. Documentation/kbuild/makefiles.txt says: --- 6.1 Set variables to tweak the build to the architecture ... CFLAGS_KERNEL $(CC) options specific for built-in $(CFLAGS_KERNEL) contains extra C compiler flags used to compile resident kernel code. CFLAGS_MODULE $(CC) options specific for modules $(CFLAGS_MODULE) contains extra C compiler flags used to compile code for loadable kernel modules. My reading of that file is these are *the* variables specifically reserved for this role. Not CFLAGS, EXTRA_CFLAGS etc. -- vda -- 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/