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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A652EC4332F for ; Mon, 16 May 2022 21:15:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349302AbiEPVPt (ORCPT ); Mon, 16 May 2022 17:15:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349133AbiEPVPT (ORCPT ); Mon, 16 May 2022 17:15:19 -0400 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B888317E28 for ; Mon, 16 May 2022 14:10:13 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2fedfd0f5b2so44473577b3.16 for ; Mon, 16 May 2022 14:10:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=BmTyv5Df5nSkvL+7PwI+QdbCtOf+cNe9vmiXu33ntQI=; b=gptOuy544f1/kWDiF/3OwcmGk6scE1yCINr+MYB1fM6wQOI6FyysBHER/hQTOSK0b+ MaV+lyiNd6H08pwzyCgMNFopwYNwi/ySdFT99VpNmwgQEw0rEy19FI8sloRnORfz9EV4 YuA8+Csdh3kYQlEkStrZ0CpdJcbK+x+1D+bsBF5GlIIousYpIEVQAE3MkbbjAsA60HDM jP9FqLob+qAOGNb6Ycu0ImKBZ1mi+hSyanggzGdQSkDubEMBbMo3sfYBAr0LDXQzZdaR JkwFLL7wq3O3irglenxPj5cF750M8ZXPb/t3wKR9aCD4OZO67kD9v4JgQWVu/llWeVVm 8ZHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BmTyv5Df5nSkvL+7PwI+QdbCtOf+cNe9vmiXu33ntQI=; b=A8OyU7FrjHk8I49C/AZqwoWIE96O65FM0VUmeJiMPmU4gVvmNOy0uXq1LNs9Lu7/CL mF8vM0yHQ53zlBClPb1hBaOHd3OG3D3e1KIxFbadCoP81tl9XSvpSly4DyzwcISrGXzt 1DhtfEkfT8fmUVlfcqB1c3aPN//WFhf16F4DxJmXMcmLrugkB5/0VxIB7eoHocPvRx9U 4QboJFsXqMUSkzhnLzKqBHDlMFvW1y0uESrTCCrZf0Opw8rgoqJFISU6KGPBVFJE4E9O 6ygadqm1+rwW67Gbry/5HS8gmsvgRSk/SrxW5XUNgCwQwZN+Aqr6MaI4X/bdTrJ/Iw12 uVdg== X-Gm-Message-State: AOAM5335PdL2IffJ+x5juMMqQEXsTxJ+q3tx9D8ptToRljp7mhgE2/tt sUzF52PB/LYozNcH48kiQVKsHBCJeUZ+2lkMdcM= X-Google-Smtp-Source: ABdhPJyMla5qPnmYHt216sR4ibgSN7vwxmKWbie1i9N4867KZ+Hc7TO27zSrR5W1Qkojj5JAsQSKdVVdoFJA+sTbuZw= X-Received: from ndesaulniers1.mtv.corp.google.com ([2620:15c:211:202:2ef0:b8de:b9c8:da45]) (user=ndesaulniers job=sendgmr) by 2002:a25:d116:0:b0:64d:6fe1:4dc5 with SMTP id i22-20020a25d116000000b0064d6fe14dc5mr11663959ybg.576.1652735412883; Mon, 16 May 2022 14:10:12 -0700 (PDT) Date: Mon, 16 May 2022 14:09:54 -0700 In-Reply-To: <20220516210954.1660716-1-ndesaulniers@google.com> Message-Id: <20220516210954.1660716-5-ndesaulniers@google.com> Mime-Version: 1.0 References: <20220516210954.1660716-1-ndesaulniers@google.com> X-Developer-Key: i=ndesaulniers@google.com; a=ed25519; pk=lvO/pmg+aaCb6dPhyGC1GyOCvPueDrrc8Zeso5CaGKE= X-Developer-Signature: v=1; a=ed25519-sha256; t=1652735394; l=3775; s=20211004; h=from:subject; bh=+s618NXBymdAo9VdYorCW3hWAXdQktAqz3laN51+p0c=; b=OVKnwODfYq9bHW9OJKqrl5qkJCDSXoxeW3Uqh+U1PMMqzJNX8xSLFGLaDqfYUfRMRaRK9PaeLrVs k97zmrYECFqtsXsQ5YEhv3E7FzsuxYTtWcX5oD9dXLdHurNhF4CA X-Mailer: git-send-email 2.36.0.550.gb090851708-goog Subject: [PATCH v3 4/4] ARM: pass -march= only to compiler From: Nick Desaulniers To: Arnd Bergmann , Ard@google.com, Biesheuvel@google.com Cc: Russell King , Masahiro Yamada , Linus Walleij , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Nick Desaulniers Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When both -march= and -Wa,-march= are specified for assembler or assembler-with-cpp sources, GCC and Clang will prefer the -Wa,-march= value but Clang will warn that -march= is unused. warning: argument unused during compilation: '-march=armv6k' [-Wunused-command-line-argument] This is the top group of warnings we observe when using clang to assemble the kernel via `ARCH=arm make LLVM=1`. Split the arch-y make variable into two, so that -march= flags only get passed to the compiler, not the assembler. -D flags are added to KBUILD_CPPFLAGS which is used for both C and assembler-with-cpp sources. Link: https://github.com/ClangBuiltLinux/linux/issues/1315 Link: https://github.com/ClangBuiltLinux/linux/issues/1587 Link: https://lore.kernel.org/llvm/628249e8.1c69fb81.d20fd.02ea@mx.google.com/ Signed-off-by: Nick Desaulniers --- arch/arm/Makefile | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 1029c2503aef..47a300f6f99c 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -57,21 +57,34 @@ endif KBUILD_CFLAGS += $(call cc-option,-fno-ipa-sra) # This selects which instruction set is used. +arch-$(CONFIG_CPU_32v7M) :=-march=armv7-m +arch-$(CONFIG_CPU_32v7) :=-march=armv7-a +arch-$(CONFIG_CPU_32v6) :=-march=armv6 +# Only override the compiler option if ARMv6. The ARMv6K extensions are +# always available in ARMv7 +ifeq ($(CONFIG_CPU_32v6),y) +arch-$(CONFIG_CPU_32v6K) :=-march=armv6k +endif +arch-$(CONFIG_CPU_32v5) :=-march=armv5te +arch-$(CONFIG_CPU_32v4T) :=-march=armv4t +arch-$(CONFIG_CPU_32v4) :=-march=armv4 +arch-$(CONFIG_CPU_32v3) :=-march=armv3m + # Note that GCC does not numerically define an architecture version # macro, but instead defines a whole series of macros which makes # testing for a specific architecture or later rather impossible. -arch-$(CONFIG_CPU_32v7M) :=-D__LINUX_ARM_ARCH__=7 -march=armv7-m -arch-$(CONFIG_CPU_32v7) :=-D__LINUX_ARM_ARCH__=7 -march=armv7-a -arch-$(CONFIG_CPU_32v6) :=-D__LINUX_ARM_ARCH__=6 -march=armv6 -# Only override the compiler opt:ion if ARMv6. The ARMv6K extensions are +cpp-$(CONFIG_CPU_32v7M) :=-D__LINUX_ARM_ARCH__=7 +cpp-$(CONFIG_CPU_32v7) :=-D__LINUX_ARM_ARCH__=7 +cpp-$(CONFIG_CPU_32v6) :=-D__LINUX_ARM_ARCH__=6 +# Only override the compiler option if ARMv6. The ARMv6K extensions are # always available in ARMv7 ifeq ($(CONFIG_CPU_32v6),y) -arch-$(CONFIG_CPU_32v6K) :=-D__LINUX_ARM_ARCH__=6 -march=armv6k +cpp-$(CONFIG_CPU_32v6K) :=-D__LINUX_ARM_ARCH__=6 endif -arch-$(CONFIG_CPU_32v5) :=-D__LINUX_ARM_ARCH__=5 -march=armv5te -arch-$(CONFIG_CPU_32v4T) :=-D__LINUX_ARM_ARCH__=4 -march=armv4t -arch-$(CONFIG_CPU_32v4) :=-D__LINUX_ARM_ARCH__=4 -march=armv4 -arch-$(CONFIG_CPU_32v3) :=-D__LINUX_ARM_ARCH__=3 -march=armv3m +cpp-$(CONFIG_CPU_32v5) :=-D__LINUX_ARM_ARCH__=5 +cpp-$(CONFIG_CPU_32v4T) :=-D__LINUX_ARM_ARCH__=4 +cpp-$(CONFIG_CPU_32v4) :=-D__LINUX_ARM_ARCH__=4 +cpp-$(CONFIG_CPU_32v3) :=-D__LINUX_ARM_ARCH__=3 # This selects how we optimise for the processor. tune-$(CONFIG_CPU_ARM7TDMI) :=-mtune=arm7tdmi @@ -123,8 +136,9 @@ AFLAGS_ISA :=$(CFLAGS_ISA) endif # Need -Uarm for gcc < 3.x +KBUILD_CPPFLAGS +=$(cpp-y) KBUILD_CFLAGS +=$(CFLAGS_ABI) $(CFLAGS_ISA) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm -KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_ISA) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float +KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_ISA) -Wa,$(arch-y) $(tune-y) -include asm/unified.h -msoft-float CHECKFLAGS += -D__arm__ -- 2.36.0.550.gb090851708-goog