Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752170Ab3HURZU (ORCPT ); Wed, 21 Aug 2013 13:25:20 -0400 Received: from mail-oa0-f43.google.com ([209.85.219.43]:53394 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751820Ab3HURZO convert rfc822-to-8bit (ORCPT ); Wed, 21 Aug 2013 13:25:14 -0400 Date: Wed, 21 Aug 2013 12:25:11 -0500 From: Rob Landley Subject: Re: [RFC] Get rid of SUBARCH To: Geert Uytterhoeven Cc: Richard Weinberger , Linux-Arch , Michal Marek , Ralf Baechle , Paul Mundt , Jeff Dike , Guan Xuetao , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , the arch/x86 maintainers , linux-kbuild , "linux-kernel@vger.kernel.org" , linux-m68k , Linux MIPS Mailing List , Linux-sh list , uml-devel In-Reply-To: (from geert@linux-m68k.org on Wed Aug 21 07:07:33 2013) X-Mailer: Balsa 2.4.11 Message-Id: <1377105911.2737.94@driftwood> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; DelSp=Yes; Format=Flowed Content-Disposition: inline Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2373 Lines: 59 On 08/21/2013 07:07:33 AM, Geert Uytterhoeven wrote: > On Wed, Aug 21, 2013 at 10:19 AM, Richard Weinberger > wrote: > > This series is an attempt to remove the SUBARCH make parameter. > > It as introduced at the times of Linux 2.5 for UML to tell the UML > > build system what the real architecture is. > > > > But we actually don't need SUBARCH, we can store this information > > in the .config file. > > Haha, now you have OS_ARCH (shouldn't that be called HOST_ARCH?) > instead, > which is available only for UM? > > > The series touches also m68k, sh, mips and unicore32. > > These architectures magically select a cross compiler if ARCH != > SUBARCH. > > Do really need that behavior? > > This does remove functionality. > It allows to build a kernel using e.g. "make ARCH=m68k". make ARCH=m68k CROSS_COMPILE=m68k- make ARCH=arm CROSS_COMPILE=armv5l- make ARCH=sparc CROSS_COMPILE=sparc- make ARCH=ppc CROSS_COMPILE=powerpc- make ARCH=sh CROSS_COMPILE=sh4- make ARCH=mips CROSS_COMPILE=mipsel- make ARCH=x86 CROSS_COMPILE=i686- make ARCH=alpha CROSS_COMPILE=alpha- Works the same way on all the targets I've tried so far. You specify the architecture, you specify the cross compiler prefix, you feed it a config file, you build. (If a target supplies its own default cross compiler prefix I just have to override it with what mine's called anyway...) > Perhaps this can be moved to generic code? Most (not all!) > cross-toolchains > are called $ARCH-{unknown-,}linux{,-gnu}. > Exceptions are e.g. am33_2.0-linux and bfin-uclinux. The linaro toolchain is arm-linux-gnueabihf- and the one on kernel.org is arm-unknown-linux-gnueabi- and the one I build is armv5l- (because the FSF's $ARCH-unknown-gnu-format-tuple-all-hail-stallman-gnu-gnu-gnu-dammit-gcc is just nuts: why would I say -linux- in a linux-to-linux toolchain? Do windows toolchains say -windows-?) Other toolchain sources use other prefixes (-unknown- is often -$VENDORNAME-), and then of course there's llvm... which is why you specify CROSS_COMPILE= on the make command line. Rob-- 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/