From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753961Ab0EFGrp (ORCPT ); Thu, 6 May 2010 02:47:45 -0400 Received: from mail-ww0-f46.google.com ([74.125.82.46]:50071 "EHLO mail-ww0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751191Ab0EFGrn convert rfc822-to-8bit (ORCPT ); Thu, 6 May 2010 02:47:43 -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=LAm5EUH9U7y+ocXiOPdd0Ja8GhVEb45xlDquw+mlb4HSoahEZjvgp7BoP38z3LLLCf ZJVldke8fXYPcWauAu28W+/w444ePiDS+zLaeQBX5ISDNh63+DJWwD+67PuDBqMqPpz0 STeW6yoKqt9CFch71XDSn29ogUR6bLJQYXKyc= MIME-Version: 1.0 In-Reply-To: <1273096160.23208.35.camel@mulgrave.site> References: <1273096160.23208.35.camel@mulgrave.site> Date: Thu, 6 May 2010 08:47:39 +0200 X-Google-Sender-Auth: 99bf05a63f417d78 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 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? 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