From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98467C04AB1 for ; Sun, 12 May 2019 03:05:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 628D3216C4 for ; Sun, 12 May 2019 03:05:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nifty.com header.i=@nifty.com header.b="wlWg+EV6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726282AbfELDF3 (ORCPT ); Sat, 11 May 2019 23:05:29 -0400 Received: from conssluserg-02.nifty.com ([210.131.2.81]:45488 "EHLO conssluserg-02.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726101AbfELDF3 (ORCPT ); Sat, 11 May 2019 23:05:29 -0400 Received: from mail-vs1-f41.google.com (mail-vs1-f41.google.com [209.85.217.41]) (authenticated) by conssluserg-02.nifty.com with ESMTP id x4C35OJf015949; Sun, 12 May 2019 12:05:25 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-02.nifty.com x4C35OJf015949 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1557630325; bh=PHCpTfH/NZWO5h1TGpj40t3Xwi0gsH7zm2ttJ8bgtjk=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=wlWg+EV6p2+hWfqagl6qKA6zeryeHT4AiHUyHpHG9bIJxM7i85RKK7kXdqcQhGRxf 2BtclUHEyO5BMWmU88/ndzk4RCVUEboitZJneF7Z4bpQJjHNn0EnrOm+T9Ktz1relF mGyx3oQBRNdzhHGfrhkGwXDtNPzYiIdnX/K11bvowIcTIpOnkvBZZMmIuZjzo4XtC6 w4R//jH/UtPPbJgBwEqLQbsaG9lrV5YAWUcNqB6AyUC1sA2LQNr8Gtx+gjZxGicUvQ GCVMes5FiCMmWUcBchcWApupfLIsgYo1mnm9MQH+1/FJTaS/wkOzg8OKQ/y7CmXhDy 1AY/FPPdyAdTA== X-Nifty-SrcIP: [209.85.217.41] Received: by mail-vs1-f41.google.com with SMTP id g187so5954926vsc.8; Sat, 11 May 2019 20:05:25 -0700 (PDT) X-Gm-Message-State: APjAAAUGQIMUOu6eONWSO++AQXD+0WvATkIdq1GIOQr8IK0AzdJTp6NX +B4hb+r4ZexDJKZP+WUU3gW3kWEIMqSrRgGJReo= X-Google-Smtp-Source: APXvYqyA7rGAUt6eu5OhrYBOkShM4Orx8bhmw0YZYMWyaFVc/82zhCGwtz59kicrBkLA2W9vTY4b8JPs7swdFESjGYU= X-Received: by 2002:a67:f443:: with SMTP id r3mr10260907vsn.179.1557630324014; Sat, 11 May 2019 20:05:24 -0700 (PDT) MIME-Version: 1.0 References: <20190509201925.189615-1-ndesaulniers@google.com> <20190511022458.GA7376@archlinux-i9> In-Reply-To: <20190511022458.GA7376@archlinux-i9> From: Masahiro Yamada Date: Sun, 12 May 2019 12:04:48 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] kbuild: add script check for cross compilation utilities To: Nathan Chancellor Cc: Nick Desaulniers , clang-built-linux , Michal Marek , Linux Kbuild mailing list , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, May 11, 2019 at 11:25 AM Nathan Chancellor wrote: > > Few comments below but nothing major, this seems to work fine as is. > > On Thu, May 09, 2019 at 01:19:21PM -0700, 'Nick Desaulniers' via Clang Built Linux wrote: > > When cross compiling via setting CROSS_COMPILE, if the prefixed tools > > are not found, then the host utilities are often instead invoked, and > > produce often difficult to understand errors. This is most commonly the > > case for developers new to cross compiling the kernel that have yet to > > install the proper cross compilation toolchain. Rather than charge > > headlong into a build that will fail obscurely, check that the tools > > exist before starting to compile, and fail with a friendly error > > message. > > This part of the commit message makes it sound like this is a generic > problem when it is actually specific to clang. make will fail on its > own when building with gcc if CROSS_COMPILE is not properly set (since > gcc won't be found). > > On a side note, seems kind of odd that clang falls back to the host > tools when a non-host --target argument is used... (how in the world is > that expected to work?) I agree. Failure is much better than falling back to host tools. -- Best Regards Masahiro Yamada