From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from moutng.kundenserver.de ([212.227.126.177]:60651 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751978AbZHLMhb (ORCPT ); Wed, 12 Aug 2009 08:37:31 -0400 From: Arnd Bergmann Subject: Re: [RFC PATCH] kbuild: Do not select symbols with unmet dependencies Date: Wed, 12 Aug 2009 14:36:58 +0200 References: <20090812112308.30683.24700.stgit@pc1117.cambridge.arm.com> In-Reply-To: <20090812112308.30683.24700.stgit@pc1117.cambridge.arm.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <200908121436.58490.arnd@arndb.de> Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Catalin Marinas Cc: linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, Sam Ravnborg On Wednesday 12 August 2009, Catalin Marinas wrote: > The "select" statement in Kconfig files allows the enabling of options > even if they have unmet direct dependencies (i.e. "depends on" expands > to "no"). Currently, the "depends on" clauses are used in calculating > the visibility but they do not affect the reverse dependencies in any > way. > > The patch introduces additional tracking of the "depends on" statements > and does not allow selecting an option if its direct dependencies are > not met, also printing a warning. > > Signed-off-by: Catalin Marinas > Cc: Sam Ravnborg I guess this will change the behaviour of a number of subsystems, likely causing unexpected regressions. I think your change makes sense, but we need to be much more careful. Can you extract a list of configuration symbols that are impacted by your patch? A possibly way out could be to annotate all of them first by changing --- config FOO bool config BAR depends on FOO config BAZ select BAR --- so that we either get config BAZ select FOO select BAR or alternatively, on a case-by-case basis config BAZ depends on FOO select BAR Once that is in place, all the symbols have a well-defined behaviour and we can safely apply your patch. Arnd <><