From patchwork Mon Aug 2 23:43:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Desaulniers X-Patchwork-Id: 12414951 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=-22.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 BC2CAC4338F for ; Mon, 2 Aug 2021 23:43:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 71D1D60EE3 for ; Mon, 2 Aug 2021 23:43:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 71D1D60EE3 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:Mime-Version: Message-Id:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=JZoqG4Dp7PIXWkp0UQ/C88wKX6fTNKF2xAJ8d+T00lA=; b=coJ VK7UOItacSO4Rq28MMqPtmU4DkG28tSTKIzPQB0mVj/1DFrfavq1uvnZkiHdtHYxeyYe25aBw8eyY jTEoEtrKbzXqafEmf+TULJgT2qkWRwQxCTZS81RwlmFn3i2ZuBOhZ7h9KysfdfFbnqWn6rV36MTff lHMpZVoyfznXKI6HqntE3LMvM/Am1MZeuRG4Ra9Ol90434vLwnCeIsGcGuJMrULuP1fRPY6JFDXgZ 2PNcgMVlmFJswkmNwqXBvEhnVVMW0TAZiqQoYt22YIjPqqjCc5ZkfFExJQMHnT5uKj6NNOS5ukf4i ekVdLPmgE/QGdaal7M6F4dAPN7vmDZw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mAhaZ-000c1N-Jh; Mon, 02 Aug 2021 23:43:19 +0000 Received: from mail-qv1-xf49.google.com ([2607:f8b0:4864:20::f49]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mAhaX-000c12-C1 for linux-riscv@lists.infradead.org; Mon, 02 Aug 2021 23:43:19 +0000 Received: by mail-qv1-xf49.google.com with SMTP id v19-20020ad455530000b029032620cab853so14196909qvy.8 for ; Mon, 02 Aug 2021 16:43:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=yy9pyQojvK7Hdmo6VGo2Lui7HtlFWMn7Zh2eGYLAN30=; b=UH3CUy9t8ryrDG4F3pv3TetQOMIQtKV6Y2LYsFhy+ponF7FuzwIOeDtuKfPCeNRPz7 qHv8bicgNi2Ms3bIMqrwpY0Md+goVKT37gdnPhhc2+yX4vG/W+X5cyUIn/dkmk2cLyF0 MRdcgQAGixOudrNX42SWMNzXoN/NtEIZjLBCDQl4+oKI8Pl+WlHKMJloWVrWpXB5Vm7P Ssr1i3ElcLtqhCrLJGNmyjpeEgyd+YFIKF+sgrp6IBqZg7VKnHjNmygADAV0uwUssdse Gi6DioUPgJIJ+D58vtaUZ8bRm/0K+LhPuz3XJtLMDhzu/CXC+QDLi2/WPpwFQ0LZjaMX rd9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=yy9pyQojvK7Hdmo6VGo2Lui7HtlFWMn7Zh2eGYLAN30=; b=h2lgdT7KQSzrH72MAWisOqk1nyXqgkU9r7gFWJdto8sH6wWgQSg6GiK5GFrPSrwr65 UwEiddzpNgzsfiZO2XEP/MJZoj69ZFUyftR1wcz5sVWDhQaXnTzSvcwun77OBIhBIkBh shrgWp9tbxiNESGG/KBCtXmiW6RV04s9Rcoc6khbOfEnYusN2wXCyHc8BhpscOZFVQ+/ jSh54SUgULxHsX9OoT3+kCs3jy1lP4bJRxuRInFnNE9oQZ8iwNjrf38mKShmS9iFTHkh ykRRkNGpCRJ0WvLJfFYGwOI3OSLwN1aeWcJKszDXZXWSD+SF2x199iLnwJGBRrBdZfyY Psgw== X-Gm-Message-State: AOAM531thM0qEQo/Zq/T7Gx1yHNAzpOpX2EvnoJ5pUNVi7fuuUHRchPx OuiUntxrQWW7ZN+3tEbZcY72xAoQYI0jXULDbbg= X-Google-Smtp-Source: ABdhPJxv56UYXw0HdwPKZZQFp3/zRO8zP8qIjavfTRIKYqCH5596UCuGHqajKqMv8WCVM5UAz4HoFd32fzVH1fyJqgg= X-Received: from ndesaulniers1.mtv.corp.google.com ([2620:15c:211:202:3db0:42c:8665:a4ae]) (user=ndesaulniers job=sendgmr) by 2002:a0c:b44b:: with SMTP id e11mr18946709qvf.38.1627947792748; Mon, 02 Aug 2021 16:43:12 -0700 (PDT) Date: Mon, 2 Aug 2021 16:43:03 -0700 Message-Id: <20210802234304.3519577-1-ndesaulniers@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.32.0.554.ge1b32706d8-goog Subject: [PATCH] scripts/Makefile.clang: default to LLVM_IAS=1 From: Nick Desaulniers To: Masahiro Yamada , Nathan Chancellor Cc: Khem Raj , Nick Desaulniers , Michal Marek , Jonathan Corbet , Paul Walmsley , Palmer Dabbelt , Albert Ou , clang-built-linux@googlegroups.com, linux-kbuild@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210802_164317_459645_4D12FBDF X-CRM114-Status: GOOD ( 12.77 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org LLVM_IAS=1 controls enabling clang's integrated assembler via -integrated-as. This was an explicit opt in until we could enable assembler support in Clang for more architecures. Now we have support and CI coverage of LLVM_IAS=1 for all architecures except a few more bugs affecting s390 and powerpc. This commit flips the default from opt in via LLVM_IAS=1 to opt out via LLVM_IAS=0. CI systems or developers that were previously doing builds with CC=clang or LLVM=1 without explicitly setting LLVM_IAS must now explicitly opt out via LLVM_IAS=0, otherwise they will be implicitly opted-in. This finally shortens the command line invocation when cross compiling with LLVM to simply: $ make ARCH=arm64 LLVM=1 Link: https://github.com/ClangBuiltLinux/linux/issues/1434 Signed-off-by: Nick Desaulniers --- Note: base is: https://lore.kernel.org/lkml/20210802183910.1802120-1-ndesaulniers@google.com/ Documentation/kbuild/llvm.rst | 14 ++++++++------ Makefile | 2 +- arch/riscv/Makefile | 2 +- scripts/Makefile.clang | 6 +++--- 4 files changed, 13 insertions(+), 11 deletions(-) base-commit: d7a86429dbc691bf540688fcc8542cc20246a85b prerequisite-patch-id: 0d3072ecb5fd06ff6fd6ea81fe601f6c54c23910 prerequisite-patch-id: 2654829756eb8a094a0ffad1679caa75a4d86619 prerequisite-patch-id: a51e7885ca2376d008bbf146a5589da247806f7b diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst index f8a360958f4c..16712fab4d3a 100644 --- a/Documentation/kbuild/llvm.rst +++ b/Documentation/kbuild/llvm.rst @@ -60,17 +60,14 @@ They can be enabled individually. The full list of the parameters: :: OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump READELF=llvm-readelf \ HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar HOSTLD=ld.lld -Currently, the integrated assembler is disabled by default. You can pass -``LLVM_IAS=1`` to enable it. +Currently, the integrated assembler is enabled by default. You can pass +``LLVM_IAS=0`` to disable it. Omitting CROSS_COMPILE ---------------------- As explained above, ``CROSS_COMPILE`` is used to set ``--target=``. -Unless ``LLVM_IAS=1`` is specified, ``CROSS_COMPILE`` is also used to derive -``--prefix=`` to search for the GNU assembler and linker. - If ``CROSS_COMPILE`` is not specified, the ``--target=`` is inferred from ``ARCH``. @@ -78,7 +75,12 @@ That means if you use only LLVM tools, ``CROSS_COMPILE`` becomes unnecessary. For example, to cross-compile the arm64 kernel:: - make ARCH=arm64 LLVM=1 LLVM_IAS=1 + make ARCH=arm64 LLVM=1 + +If ``LLVM_IAS=0`` is specified, ``CROSS_COMPILE`` is also used to derive +``--prefix=`` to search for the GNU assembler and linker. :: + + make ARCH=arm64 LLVM=1 LLVM_IAS=0 CROSS_COMPILE=aarch64-linux-gnu- Supported Architectures ----------------------- diff --git a/Makefile b/Makefile index 444558e62cbc..b24b48c9ebb7 100644 --- a/Makefile +++ b/Makefile @@ -845,7 +845,7 @@ else DEBUG_CFLAGS += -g endif -ifneq ($(LLVM_IAS),1) +ifeq ($(LLVM_IAS),0) KBUILD_AFLAGS += -Wa,-gdwarf-2 endif diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index bc74afdbf31e..807f7c94bc6f 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -41,7 +41,7 @@ endif ifeq ($(CONFIG_LD_IS_LLD),y) KBUILD_CFLAGS += -mno-relax KBUILD_AFLAGS += -mno-relax -ifneq ($(LLVM_IAS),1) +ifeq ($(LLVM_IAS),0) KBUILD_CFLAGS += -Wa,-mno-relax KBUILD_AFLAGS += -Wa,-mno-relax endif diff --git a/scripts/Makefile.clang b/scripts/Makefile.clang index 1f4e3eb70f88..3ae63bd35582 100644 --- a/scripts/Makefile.clang +++ b/scripts/Makefile.clang @@ -22,12 +22,12 @@ else CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) endif # CROSS_COMPILE -ifeq ($(LLVM_IAS),1) -CLANG_FLAGS += -integrated-as -else +ifeq ($(LLVM_IAS),0) CLANG_FLAGS += -no-integrated-as GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit)) CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE)) +else +CLANG_FLAGS += -integrated-as endif CLANG_FLAGS += -Werror=unknown-warning-option KBUILD_CFLAGS += $(CLANG_FLAGS)