From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758219Ab0EFNgh (ORCPT ); Thu, 6 May 2010 09:36:37 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:61872 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751935Ab0EFNgd convert rfc822-to-8bit (ORCPT ); Thu, 6 May 2010 09:36:33 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=VDm8Hafb8Yw7Cdhk/aPl66ISwB1fQF3wNi2K/af+4rimsswA+sQeHhWkke+6oKsS+0 Ge8LmqCtQ4W+8WUwUMErcZ8KGK4CUyglMPXFe8rwaBaROoePan0dV5aq8UVGPRuxhP1C afsh4TfOq36/YVHF3AII09k0G6+cw/yjs+zos= MIME-Version: 1.0 In-Reply-To: <1273151844.23208.48.camel@mulgrave.site> References: <1273096160.23208.35.camel@mulgrave.site> <1273151844.23208.48.camel@mulgrave.site> Date: Thu, 6 May 2010 15:36:31 +0200 X-Google-Sender-Auth: c0eff55d107477fe Message-ID: Subject: Re: kbuild: fixing the select problem From: Geert Uytterhoeven To: James Bottomley Cc: linux-arch@vger.kernel.org, linux-kernel , Sam Ravnborg , linux-kbuild@vger.kernel.org, Randy Dunlap Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 6, 2010 at 15:17, James Bottomley wrote: > On Thu, 2010-05-06 at 08:47 +0200, Geert Uytterhoeven wrote: >> On Wed, May 5, 2010 at 23:49, James Bottomley >> wrote: >> > [Sam: I know you don't maintain kbuild anymore, but since you have the >> > most experience, if you could find time to comment, I'd be grateful] >> > >> > The select problem is that the kbuild select directive will turn a >> > symbol on without reference to its dependencies.  This, in turn, means >> > that either selected symbols must select their dependencies, or that >> > people using select have to be aware of the selected symbol's dependency >> > and build those dependencies into their symbol (leading to duplication >> > and the possibility of getting the dependencies out of sync).  We use >> > select for the scsi transport classes, so we run into this problem in >> > SCSI quite a lot. >> > >> > I think the correct fix is to make a symbol that selects another symbol >> > automatically inherit all of the selected symbol's dependencies. >> >> What if there's a good reason the selected symbol has this dependency? >> E.g. it depends on a critical feature not available? Like CONFIG_HAS_IOMEM? > > I don't quite understand the question.  If a selected symbol has a > critical dependency which is config'd to N then the build usually > breaks ... that's what I'm calling the select problem.  I thought > CONFIG_HAS_IOMEM was usually selected by the architecture, though.  In > the new proposal, we wouldn't be able to generate the invalid > configuration in the first place. Sorry, my fault, -EREPLY_TOO_EARLY_AFTER_WAKEUP. Upon rereading what you actually wrote, it made complete sense, and my question didn't. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds