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=-14.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,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 AAB84C433DB for ; Tue, 9 Mar 2021 19:56:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 790D965259 for ; Tue, 9 Mar 2021 19:56:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231636AbhCIT4N (ORCPT ); Tue, 9 Mar 2021 14:56:13 -0500 Received: from conssluserg-01.nifty.com ([210.131.2.80]:42753 "EHLO conssluserg-01.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230431AbhCIT4I (ORCPT ); Tue, 9 Mar 2021 14:56:08 -0500 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (authenticated) by conssluserg-01.nifty.com with ESMTP id 129Jtd8V015140; Wed, 10 Mar 2021 04:55:39 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-01.nifty.com 129Jtd8V015140 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1615319739; bh=O2Wusp+oF1an+HCfKF/8accMBu76kIYY85AHixnE3LA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=2tBjBYarT9iWOhUds3YLiEf+1/6OXbrgghJw2c9e7XL9ITknLmpugZGp7pPcWxBuu x1JMBapghXLDHko+27MAgrNA+VkWcZkW9/j8IhkXpvpKD7uVfBvqf5dWnCm7tc9JRg nFpOF9yNiz/BP3zHTmFfCka/Y6U936t+M1lV0jb4s+ZTh7dPmrPF1mMJ2nJXlht901 m7N5WkIfns+Pjw55Qlo7rKONiuAP5XrCTavOqKBICimUfCTyWirQ/R/aSH5kXXSbnd 3ylEgcGx54V+Qc5s7v2uUEQFGhATUkSZ5C2CiSuj/QWPjTpQ+G+vKZmr85SNMd3h9Z wRNmfO720Przw== X-Nifty-SrcIP: [209.85.214.171] Received: by mail-pl1-f171.google.com with SMTP id n17so3600061plc.7; Tue, 09 Mar 2021 11:55:39 -0800 (PST) X-Gm-Message-State: AOAM533GIi30z1z2ZLq+Eb0iCk0nubCdp8Sw947Ol2RpiupxafEfLOgr ZnKe93ivYtITp0h/Ni27ED/aKVFJMjr+Y2Eruvw= X-Google-Smtp-Source: ABdhPJxFjRqVc0PsKtmDIrLRimcT42M0ZYqKVZIigD3lor/la9zVBXvRgb+kKLXQ3Q0Z8aPs9E8uwsYFUdL7kv8n09I= X-Received: by 2002:a17:90a:5510:: with SMTP id b16mr6321761pji.87.1615319738849; Tue, 09 Mar 2021 11:55:38 -0800 (PST) MIME-Version: 1.0 References: <20210302210646.3044738-1-nathan@kernel.org> <20210302210646.3044738-2-nathan@kernel.org> In-Reply-To: <20210302210646.3044738-2-nathan@kernel.org> From: Masahiro Yamada Date: Wed, 10 Mar 2021 04:55:00 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 2/2] Makefile: Only specify '--prefix=' when building with clang + GNU as To: Nathan Chancellor Cc: Michal Marek , Nick Desaulniers , Linux Kbuild mailing list , Linux Kernel Mailing List , clang-built-linux Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 3, 2021 at 6:07 AM Nathan Chancellor wrote: > > When building with LLVM_IAS=1, there is no point to specifying > '--prefix=' because that flag is only used to find the cross assembler, > which is clang itself when building with LLVM_IAS=1. All of the other > tools are invoked directly from PATH or a full path specified via the > command line, which does not depend on the value of '--prefix='. > > Sharing commands to reproduce issues becomes a little bit easier without > a '--prefix=' value because that '--prefix=' value is specific to a > user's machine due to it being an absolute path. > > Signed-off-by: Nathan Chancellor I was tricked by a couple of Reviewed-by/Tested-by tags. With this patch applied, the code looks as follows: ifneq ($(CROSS_COMPILE),) CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) ifneq ($(LLVM_IAS),1) GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) CLANG_FLAGS += -no-integrated-as endif endif For the native build (empty CROSS_COMPILE), you cannot add -no-integrated-as. I dropped this from my tree. Is the correct code as follows? ifneq ($(LLVM_IAS),1) CLANG_FLAGS += -no-integrated-as ifneq ($(CROSS_COMPILE),) CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) endif endif > --- > Makefile | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/Makefile b/Makefile > index c20f0ad8be73..0413b8c594cd 100644 > --- a/Makefile > +++ b/Makefile > @@ -566,12 +566,12 @@ CC_VERSION_TEXT = $(shell $(CC) --version 2>/dev/null | head -n 1 | sed 's/\#//g > ifneq ($(findstring clang,$(CC_VERSION_TEXT)),) > ifneq ($(CROSS_COMPILE),) > CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) > +ifneq ($(LLVM_IAS),1) > GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) > CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) > -endif > -ifneq ($(LLVM_IAS),1) > CLANG_FLAGS += -no-integrated-as > endif > +endif > CLANG_FLAGS += -Werror=unknown-warning-option > KBUILD_CFLAGS += $(CLANG_FLAGS) > KBUILD_AFLAGS += $(CLANG_FLAGS) > -- > 2.31.0.rc0.75.gec125d1bc1 > -- Best Regards Masahiro Yamada