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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 D8FFEC43381 for ; Wed, 27 Mar 2019 18:04:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD09121855 for ; Wed, 27 Mar 2019 18:04:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553709865; bh=AqdzoIJJu9cpZJrqevo1aBmtgqV79O2mnfJMJkW4fZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IPULiXPoy3M+rc2lt3bYLLqX9dr4w0rY6kXaLs8f5jWr/VboDWExyXxgVgEyb64jQ nggXPl9U7wuB7iycpq3i2ZLJcHLhEW5m5UQHWY1aNlBCQm/TVKe2oCcpV/UwSb+Z5b fYTMHwYxIqyo8Rxu4R3Z+0fW5mBVy6jDnJXz80d8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733257AbfC0SEX (ORCPT ); Wed, 27 Mar 2019 14:04:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:44852 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733210AbfC0SEQ (ORCPT ); Wed, 27 Mar 2019 14:04:16 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0B7D92184C; Wed, 27 Mar 2019 18:04:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553709855; bh=AqdzoIJJu9cpZJrqevo1aBmtgqV79O2mnfJMJkW4fZA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qdj1lkK0DsjFIgE1TyMKRQiXOhgrEkdTTAU0OBtHpdhoTNVKfpaf1ZLoncOTMcBnu ZiPcBYpoL04miJDB2M9tzKHsHAKri8PBsmr7x6QzObkWUjyC0cvyWJxfX+WZAxYPGc /qXKRjtT1u1DUlumTn/73YV7M/QLCZn6zUoO66Zk= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masahiro Yamada , Sasha Levin , linux-kbuild@vger.kernel.org Subject: [PATCH AUTOSEL 5.0 075/262] kbuild: make -r/-R effective in top Makefile for old Make versions Date: Wed, 27 Mar 2019 13:58:50 -0400 Message-Id: <20190327180158.10245-75-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327180158.10245-1-sashal@kernel.org> References: <20190327180158.10245-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Masahiro Yamada [ Upstream commit 3812b8c5c5d527239ac015f1f2c7654da7fcfbba ] Adding -rR to MAKEFLAGS is important because we do not want to be bothered by built-in implicit rules or variables. One problem that used to exist in older GNU Make versions is MAKEFLAGS += -rR ... does not become effective in the current Makefile. When you are building with O= option, it becomes effective in the top Makefile since it recurses via 'sub-make' target. Otherwise, the top Makefile tries implicit rules. That is why we explicitly add empty rules for Makefiles, but we often miss to do that. In fact, adding -d option to older GNU Make versions shows it is trying a bunch of implicit pattern rules. Considering target file `scripts/Makefile.kcov'. Looking for an implicit rule for `scripts/Makefile.kcov'. Trying pattern rule with stem `Makefile.kcov'. Trying implicit prerequisite `scripts/Makefile.kcov.o'. Trying pattern rule with stem `Makefile.kcov'. Trying implicit prerequisite `scripts/Makefile.kcov.c'. Trying pattern rule with stem `Makefile.kcov'. Trying implicit prerequisite `scripts/Makefile.kcov.cc'. Trying pattern rule with stem `Makefile.kcov'. Trying implicit prerequisite `scripts/Makefile.kcov.C'. ... This issue was fixed by GNU Make commit 58dae243526b ("[Savannah #20501] Handle adding -r/-R to MAKEFLAGS in the makefile"). So, it is no longer a problem if you use GNU Make 4.0 or later. However, older versions are still widely used. So, I decided to patch the kernel Makefile to invoke sub-make regardless of O= option. This will allow further cleanups. Signed-off-by: Masahiro Yamada Signed-off-by: Sasha Levin --- Makefile | 48 ++++++++++++++++++++++++++---------------------- 1 file changed, 26 insertions(+), 22 deletions(-) diff --git a/Makefile b/Makefile index 89af52ca0ba5..efec82635ac5 100644 --- a/Makefile +++ b/Makefile @@ -15,19 +15,6 @@ NAME = Shy Crocodile PHONY := _all _all: -# Do not use make's built-in rules and variables -# (this increases performance and avoids hard-to-debug behaviour) -MAKEFLAGS += -rR - -# Avoid funny character set dependencies -unexport LC_ALL -LC_COLLATE=C -LC_NUMERIC=C -export LC_COLLATE LC_NUMERIC - -# Avoid interference with shell env settings -unexport GREP_OPTIONS - # We are using a recursive build, so we need to do a little thinking # to get the ordering right. # @@ -44,6 +31,21 @@ unexport GREP_OPTIONS # descending is started. They are now explicitly listed as the # prepare rule. +ifneq ($(sub-make-done),1) + +# Do not use make's built-in rules and variables +# (this increases performance and avoids hard-to-debug behaviour) +MAKEFLAGS += -rR + +# Avoid funny character set dependencies +unexport LC_ALL +LC_COLLATE=C +LC_NUMERIC=C +export LC_COLLATE LC_NUMERIC + +# Avoid interference with shell env settings +unexport GREP_OPTIONS + # Beautify output # --------------------------------------------------------------------------- # @@ -112,7 +114,6 @@ export quiet Q KBUILD_VERBOSE # KBUILD_SRC is not intended to be used by the regular user (for now), # it is set on invocation of make with KBUILD_OUTPUT or O= specified. -ifeq ($(KBUILD_SRC),) # OK, Make called in directory where kernel src resides # Do we want to locate output files in a separate directory? @@ -142,6 +143,13 @@ $(if $(KBUILD_OUTPUT),, \ # 'sub-make' below. MAKEFLAGS += --include-dir=$(CURDIR) +else + +# Do not print "Entering directory ..." at all for in-tree build. +MAKEFLAGS += --no-print-directory + +endif # ifneq ($(KBUILD_OUTPUT),) + PHONY += $(MAKECMDGOALS) sub-make $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make @@ -149,16 +157,12 @@ $(filter-out _all sub-make $(CURDIR)/Makefile, $(MAKECMDGOALS)) _all: sub-make # Invoke a second make in the output directory, passing relevant variables sub-make: - $(Q)$(MAKE) -C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR) \ + $(Q)$(MAKE) sub-make-done=1 \ + $(if $(KBUILD_OUTPUT),-C $(KBUILD_OUTPUT) KBUILD_SRC=$(CURDIR)) \ -f $(CURDIR)/Makefile $(filter-out _all sub-make,$(MAKECMDGOALS)) -# Leave processing to above invocation of make -skip-makefile := 1 -endif # ifneq ($(KBUILD_OUTPUT),) -endif # ifeq ($(KBUILD_SRC),) - +else # sub-make-done # We process the rest of the Makefile if this is the final invocation of make -ifeq ($(skip-makefile),) # Do not print "Entering directory ...", # but we want to display it when entering to the output directory @@ -1757,7 +1761,7 @@ $(cmd_files): ; # Do not try to update included dependency files endif # ifeq ($(config-targets),1) endif # ifeq ($(mixed-targets),1) -endif # skip-makefile +endif # sub-make-done PHONY += FORCE FORCE: -- 2.19.1