From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from terminus.zytor.com ([198.137.202.10]:34748 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756286Ab2BXWZE (ORCPT ); Fri, 24 Feb 2012 17:25:04 -0500 Message-ID: <4F480DDF.2080000@zytor.com> Date: Fri, 24 Feb 2012 14:23:27 -0800 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: Kconfig and toolchain dependencies References: <4F2C51A5.1040800@zytor.com> <4F480CDE.8010605@suse.cz> In-Reply-To: <4F480CDE.8010605@suse.cz> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: Michal Marek Cc: "linux-kbuild@vger.kernel.org" , Linux Kernel Mailing List , Ingo Molnar On 02/24/2012 02:19 PM, Michal Marek wrote: > Dne 3.2.2012 22:29, H. Peter Anvin napsal(a): >> Right now, we don't have a good way to encode toolchain dependencies in >> Kconfig. This makes it hard to add optional features which depend on >> newer toolchain features. >> >> If we just add them, then it breaks all*config and randconfig on >> platforms with the older toolchains unless the user manually adds >> exclusion rules. This is bad for testing. >> >> It seems relatively straightforward to do if we were to manifest some >> CONFIG_ variables based on the target toolchain, e.g. >> >> CONFIG_GCC=0x040601 > > (sorry for the late reply) > > It would be a bit tricky, because the toolchain version depends also on > CONFIG_CROSS_COMPILE. So Kconfig would need to know the semantics of > CONFIG_CROSS_COMPILE and CONFIG_GCC and the dependency of the latter on > the former. > > Michal Either way it would mean having to regenerate the config when the toolchain changes. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.