From patchwork Thu Oct 28 13:43:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 12590231 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F140C433EF for ; Thu, 28 Oct 2021 13:45:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CD25610A0 for ; Thu, 28 Oct 2021 13:45:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230297AbhJ1Nrp (ORCPT ); Thu, 28 Oct 2021 09:47:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49282 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229887AbhJ1Nro (ORCPT ); Thu, 28 Oct 2021 09:47:44 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A212C061570; Thu, 28 Oct 2021 06:45:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:In-Reply-To:References; bh=RseIqWUemXBQX2ZvxpTektn5wh2Dt3uxLghf6LdyvGI=; b=rcJB8/YGkFoVKJhJpe/4YdGPn+ pBn68RiGAv0WKkT5phwJNeWyaa8gLk8Ffn9zWBtI26ZCLRoGwMzbxJ+uZs9ASbSiInNUvt1+Nodn3 BbSE4rg0mjy9trP4GMt8YK7rmXJpLDwbAXK3F5iLnVSSX6l0A6UmngV+aZtdDmwx/zQvYC4XUbjze BgEDDhohhoIqevQa/bYDc7GJWpe40RYSTqMxjbc4E5ylMRcQ1hG0B7NtProsd1YAXBjhxv+jw6LXW 5JXcLfE2rcAjg0SaG4ABudSmAp9cXTTB/8FnZfMUSjvvx/77RgThYErHyLSlmbhpK6R7PfU+BT9N9 Wn/mwjPA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1mg5h8-000njz-Fy; Thu, 28 Oct 2021 13:44:09 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 917313001BF; Thu, 28 Oct 2021 15:43:48 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 43F71200D2747; Thu, 28 Oct 2021 15:43:48 +0200 (CEST) Date: Thu, 28 Oct 2021 15:43:48 +0200 From: Peter Zijlstra To: nathan@kernel.org, ndesaulniers@google.com, masahiroy@kernel.org, michal.lkml@markovi.net Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH] kbuild: Support clang-$ver builds Message-ID: MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Hi, Debian (and derived) distros ship their compilers as -$ver suffixed binaries. For gcc it is sufficent to use: $ make CC=gcc-12 However, clang builds (esp. clang-lto) need a whole array of tools to be exactly right, leading to unweildy stuff like: $ make CC=clang-13 LD=ld.lld=14 AR=llvm-ar-13 NM=llvm-nm-13 OBJCOPY=llvm-objcopy-13 OBJDUMP=llvm-objdump-13 READELF=llvm-readelf-13 STRIP=llvm-strip-13 LLVM=1 which is, quite franktly, totally insane and unusable. Instead use the already mandatory LLVM variable to convey this, enabling one such as myself to use: $ make LLVM=-13 This also lets one quickly test different clang versions. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Peter Zijlstra (Intel) --- Makefile | 27 +++++++++++++++++---------- tools/scripts/Makefile.include | 23 +++++++++++++++-------- 2 files changed, 32 insertions(+), 18 deletions(-) diff --git a/Makefile b/Makefile index 30c7c81d0437..a38f38f7f190 100644 --- a/Makefile +++ b/Makefile @@ -423,9 +423,16 @@ HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null) HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null) HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null) +# When LLVM=-ver use clang-ver binaries, useful for Debian and other +# multi-version setups +ifeq ($(shell test $(LLVM) -lt 0; echo $$?),0) +LLVM_SFX=$(LLVM) +export LLVM_SFX +endif + ifneq ($(LLVM),) -HOSTCC = clang -HOSTCXX = clang++ +HOSTCC = clang$(LLVM_SFX) +HOSTCXX = clang++$(LLVM_SFX) else HOSTCC = gcc HOSTCXX = g++ @@ -443,14 +450,14 @@ KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS) # Make variables (CC, etc...) CPP = $(CC) -E ifneq ($(LLVM),) -CC = clang -LD = ld.lld -AR = llvm-ar -NM = llvm-nm -OBJCOPY = llvm-objcopy -OBJDUMP = llvm-objdump -READELF = llvm-readelf -STRIP = llvm-strip +CC = clang$(LLVM_SFX) +LD = ld.lld$(LLVM_SFX) +AR = llvm-ar$(LLVM_SFX) +NM = llvm-nm$(LLVM_SFX) +OBJCOPY = llvm-objcopy$(LLVM_SFX) +OBJDUMP = llvm-objdump$(LLVM_SFX) +READELF = llvm-readelf$(LLVM_SFX) +STRIP = llvm-strip$(LLVM_SFX) else CC = $(CROSS_COMPILE)gcc LD = $(CROSS_COMPILE)ld diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include index 071312f5eb92..a2b53cc91378 100644 --- a/tools/scripts/Makefile.include +++ b/tools/scripts/Makefile.include @@ -51,12 +51,19 @@ define allow-override $(eval $(1) = $(2))) endef +# When LLVM=-ver use clang-ver binaries, useful for Debian and other +# multi-version setups +ifeq ($(shell test $(LLVM) -lt 0; echo $$?),0) +LLVM_SFX=$(LLVM) +export LLVM_SFX +endif + ifneq ($(LLVM),) -$(call allow-override,CC,clang) -$(call allow-override,AR,llvm-ar) -$(call allow-override,LD,ld.lld) -$(call allow-override,CXX,clang++) -$(call allow-override,STRIP,llvm-strip) +$(call allow-override,CC,clang$(LLVM_SFX)) +$(call allow-override,AR,llvm-ar$(LLVM_SFX)) +$(call allow-override,LD,ld.lld$(LLVM_SFX)) +$(call allow-override,CXX,clang++$(LLVM_SFX)) +$(call allow-override,STRIP,llvm-strip$(LLVM_SFX)) else # Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix. $(call allow-override,CC,$(CROSS_COMPILE)gcc) @@ -69,9 +76,9 @@ endif CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?) ifneq ($(LLVM),) -HOSTAR ?= llvm-ar -HOSTCC ?= clang -HOSTLD ?= ld.lld +HOSTAR ?= llvm-ar$(LLVM_SFX) +HOSTCC ?= clang$(LLVM_SFX) +HOSTLD ?= ld.lld$(LLVM_SFX) else HOSTAR ?= ar HOSTCC ?= gcc