From patchwork Sat Aug 31 16:25:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 11124933 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 157E51399 for ; Sat, 31 Aug 2019 16:26:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 97B2022D37 for ; Sat, 31 Aug 2019 16:26:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nifty.com header.i=@nifty.com header.b="nxBWCbZc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728244AbfHaQ0s (ORCPT ); Sat, 31 Aug 2019 12:26:48 -0400 Received: from conuserg-12.nifty.com ([210.131.2.79]:41668 "EHLO conuserg-12.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728119AbfHaQ0r (ORCPT ); Sat, 31 Aug 2019 12:26:47 -0400 Received: from grover.flets-west.jp (softbank126125143222.bbtec.net [126.125.143.222]) (authenticated) by conuserg-12.nifty.com with ESMTP id x7VGQ14v028152; Sun, 1 Sep 2019 01:26:01 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-12.nifty.com x7VGQ14v028152 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1567268761; bh=SLmzLQSSgz61XqmfX34aySvXBG0lEPr1RYwtTQ3yRZs=; h=From:To:Cc:Subject:Date:From; b=nxBWCbZcw9l/4NjxHH+8xdAgWNT6sIEBuw6rXKpR8OAXIAeEUihtiNs7FSwSIn9aJ 52el7fnPLRhAcnXi+5Bp9GAwDVcOYDXpwzhJr9aWLOUQr7PbW8nf4DnDpNM6lFQKj0 sxnPIFOJ6FDe/nDeNzvWSfTexWqJjwy6X8wk2Yl64GTAV99Y36j3O4kUEOcxiAlYVC QTFwJ0djMR2VkXHBZjrY7hXlExkEm0kb8/WdkCKtzsDEOCoZXwrkHY0Pa0qWFPwGcR VElrZ9ql/j9xz7HDjoTNZzRBlS0nZeC253HtmtuaCnXlFJHutKq1Ni0gtjrkoC4N95 oi68cjL3229bQ== X-Nifty-SrcIP: [126.125.143.222] From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: Nick Desaulniers , Nathan Chancellor , Sedat Dilek , Masahiro Yamada , Michal Marek , clang-built-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: [PATCH v3 1/2] kbuild: refactor scripts/Makefile.extrawarn Date: Sun, 1 Sep 2019 01:25:54 +0900 Message-Id: <20190831162555.31887-1-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Instead of the warning-[123] magic, let's accumulate compiler options to KBUILD_CFLAGS directly as the top Makefile does. I think this makes easier to understand what is going on in this file. This commit slightly changes the behavior, I think all of which are OK. [1] Currently, cc-option calls are needlessly evaluated. For example, warning-3 += $(call cc-option, -Wpacked-bitfield-compat) needs evaluating only when W=3, but it is actually evaluated for W=1, W=2 as well. With this commit, only relevant cc-option calls will be evaluated. This is a slight optimization. [2] Currently, unsupported level like W=4 is checked by: $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) This will no longer be checked, but I do not think it is a big deal. [3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat, Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2, and W=3. With this commit, they will be warned only by W=1. I think this is a more correct behavior since each warning belongs to only one group. For understanding this commit correctly: We have 3 warning groups, W=1, W=2, and W=3. You may think W=3 has a higher level than W=1, but they are actually independent. If you like, you can combine them like W=13. To enable all the warnings, you can pass W=123. It is shown by 'make help', but not noticed much. Since we support W= combination, there should not exist intersection among the three groups. If we enable Winitializer-overrides for W=1, we do not need to for W=2 or W=3. This is the reason why I think the change [3] makes sense. The documentation says -Winitializer-overrides is enabled by default. (https://clang.llvm.org/docs/DiagnosticsReference.html#winitializer-overrides) We negate it by passing -Wno-initializer-overrides for the normal build, but we do not do that for W=1. This means, W=1 effectively enables -Winitializer-overrides by the clang's default. The same for the other three. Add comments in case people are confused with the code. Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor Tested-by: Sedat Dilek Acked-by: Nick Desaulniers Acked-by: Miguel Ojeda --- Changes in v3: - Added yet more comments. Fix grammatical mistake 'does' -> 'do'. Changes in v2: - Added comments and more commit log scripts/Makefile.extrawarn | 106 ++++++++++++++++++++----------------- 1 file changed, 56 insertions(+), 50 deletions(-) diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index a74ce2e3c33e..d226c5fb13e2 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -1,14 +1,9 @@ # SPDX-License-Identifier: GPL-2.0 # ========================================================================== -# # make W=... settings # -# W=1 - warnings that may be relevant and does not occur too often -# W=2 - warnings that occur quite often but may still be relevant -# W=3 - the more obscure warnings, can most likely be ignored -# -# $(call cc-option, -W...) handles gcc -W.. options which -# are not supported by all versions of the compiler +# There are three warning groups enabled by W=1, W=2, W=3. +# They are independent, and can be combined like W=12 or W=123. # ========================================================================== KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned) @@ -17,58 +12,69 @@ ifeq ("$(origin W)", "command line") export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W) endif -ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS -warning- := $(empty) +# +# W=1 - warnings which may be relevant and do not occur too often +# +ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) -warning-1 := -Wextra -Wunused -Wno-unused-parameter -warning-1 += -Wmissing-declarations -warning-1 += -Wmissing-format-attribute -warning-1 += -Wmissing-prototypes -warning-1 += -Wold-style-definition -warning-1 += -Wmissing-include-dirs -warning-1 += $(call cc-option, -Wunused-but-set-variable) -warning-1 += $(call cc-option, -Wunused-const-variable) -warning-1 += $(call cc-option, -Wpacked-not-aligned) -warning-1 += $(call cc-option, -Wstringop-truncation) +KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter +KBUILD_CFLAGS += -Wmissing-declarations +KBUILD_CFLAGS += -Wmissing-format-attribute +KBUILD_CFLAGS += -Wmissing-prototypes +KBUILD_CFLAGS += -Wold-style-definition +KBUILD_CFLAGS += -Wmissing-include-dirs +KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable) +KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable) +KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned) +KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation) # The following turn off the warnings enabled by -Wextra -warning-1 += -Wno-missing-field-initializers -warning-1 += -Wno-sign-compare - -warning-2 += -Wcast-align -warning-2 += -Wdisabled-optimization -warning-2 += -Wnested-externs -warning-2 += -Wshadow -warning-2 += $(call cc-option, -Wlogical-op) -warning-2 += -Wmissing-field-initializers -warning-2 += -Wsign-compare -warning-2 += $(call cc-option, -Wmaybe-uninitialized) -warning-2 += $(call cc-option, -Wunused-macros) - -warning-3 := -Wbad-function-cast -warning-3 += -Wcast-qual -warning-3 += -Wconversion -warning-3 += -Wpacked -warning-3 += -Wpadded -warning-3 += -Wpointer-arith -warning-3 += -Wredundant-decls -warning-3 += -Wswitch-default -warning-3 += $(call cc-option, -Wpacked-bitfield-compat) - -warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) - -ifeq ("$(strip $(warning))","") - $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) -endif +KBUILD_CFLAGS += -Wno-missing-field-initializers +KBUILD_CFLAGS += -Wno-sign-compare -KBUILD_CFLAGS += $(warning) else +# Some diagnostics enabled by default are noisy. +# Suppress them by using -Wno... except for W=1. + ifdef CONFIG_CC_IS_CLANG KBUILD_CFLAGS += -Wno-initializer-overrides KBUILD_CFLAGS += -Wno-format KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += -Wno-format-zero-length endif + +endif + +# +# W=2 - warnings which occur quite often but may still be relevant +# +ifneq ($(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) + +KBUILD_CFLAGS += -Wcast-align +KBUILD_CFLAGS += -Wdisabled-optimization +KBUILD_CFLAGS += -Wnested-externs +KBUILD_CFLAGS += -Wshadow +KBUILD_CFLAGS += $(call cc-option, -Wlogical-op) +KBUILD_CFLAGS += -Wmissing-field-initializers +KBUILD_CFLAGS += -Wsign-compare +KBUILD_CFLAGS += $(call cc-option, -Wmaybe-uninitialized) +KBUILD_CFLAGS += $(call cc-option, -Wunused-macros) + +endif + +# +# W=3 - more obscure warnings, can most likely be ignored +# +ifneq ($(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) + +KBUILD_CFLAGS += -Wbad-function-cast +KBUILD_CFLAGS += -Wcast-qual +KBUILD_CFLAGS += -Wconversion +KBUILD_CFLAGS += -Wpacked +KBUILD_CFLAGS += -Wpadded +KBUILD_CFLAGS += -Wpointer-arith +KBUILD_CFLAGS += -Wredundant-decls +KBUILD_CFLAGS += -Wswitch-default +KBUILD_CFLAGS += $(call cc-option, -Wpacked-bitfield-compat) + endif From patchwork Sat Aug 31 16:25:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 11124935 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3DE171399 for ; Sat, 31 Aug 2019 16:27:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1306322D37 for ; Sat, 31 Aug 2019 16:27:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nifty.com header.i=@nifty.com header.b="BqeiHJd8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728361AbfHaQ1B (ORCPT ); Sat, 31 Aug 2019 12:27:01 -0400 Received: from conuserg-12.nifty.com ([210.131.2.79]:41942 "EHLO conuserg-12.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728350AbfHaQ1B (ORCPT ); Sat, 31 Aug 2019 12:27:01 -0400 Received: from grover.flets-west.jp (softbank126125143222.bbtec.net [126.125.143.222]) (authenticated) by conuserg-12.nifty.com with ESMTP id x7VGQ14w028152; Sun, 1 Sep 2019 01:26:01 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-12.nifty.com x7VGQ14w028152 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1567268762; bh=Ui9mzwIcf6q3fAmho+x2Mpzgo39jfnuLRThfNlp/A5I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BqeiHJd8BBtWNXYB0xBm5fvUxh4XoT/v4U+vAnVIrlwARQTZyWBBIO7Dfk03n2nfd kPCeeeU7jt6TY8MEv7m/LUtus0JKQ8xzA0yZjRfT4w/p4YTK8sH/iUG9ToI2WBi74n H3p24RLsMyXvABdZeFI+7ieQMPhDauOuZdNmpMfRQRmLqC+Lp9xdbgjwSA9xpvhFyW If6Xwh6c/ZaQP7sBRnOOphlgNHOuts3uC6Usg0HYgukpRC6cexmFyLI8bPPlGcAUWY cOrMc/fe1X3BWBJG5OHOh2djyA69V2oxqJ3a2ajWyTfOnEiVotc88HmMP3ZTB2MOkm 0lvTqA9CYZp1w== X-Nifty-SrcIP: [126.125.143.222] From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: Nick Desaulniers , Nathan Chancellor , Sedat Dilek , Masahiro Yamada , Jonathan Corbet , Michal Marek , clang-built-linux@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 2/2] kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN Date: Sun, 1 Sep 2019 01:25:55 +0900 Message-Id: <20190831162555.31887-2-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190831162555.31887-1-yamada.masahiro@socionext.com> References: <20190831162555.31887-1-yamada.masahiro@socionext.com> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org KBUILD_ENABLE_EXTRA_GCC_CHECKS started as a switch to add extra warning options for GCC, but now it is a historical misnomer since we use it also for Clang, DTC, and even kernel-doc. Rename it to more sensible, and shorter KBUILD_EXTRA_WARN. For the backward compatibility, KBUILD_ENABLE_EXTRA_GCC_CHECKS is still supported (but not advertised in the documentation). I also fixed up 'make help', and updated the documentation. Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor Reviewed-by: Nick Desaulniers Reviewed-by: Sedat Dilek --- Changes in v3: - new patch Changes in v2: None Documentation/kbuild/kbuild.rst | 14 +++++++++----- Makefile | 2 +- scripts/Makefile.build | 2 +- scripts/Makefile.extrawarn | 13 +++++++++---- scripts/Makefile.lib | 4 ++-- scripts/genksyms/Makefile | 2 +- 6 files changed, 23 insertions(+), 14 deletions(-) diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst index 62f9d86c082c..f1e5dce86af7 100644 --- a/Documentation/kbuild/kbuild.rst +++ b/Documentation/kbuild/kbuild.rst @@ -105,6 +105,15 @@ The output directory can also be specified using "O=...". Setting "O=..." takes precedence over KBUILD_OUTPUT. +KBUILD_EXTRA_WARN +----------------- +Specify the extra build checks. The same value can be assigned by passing +W=... from the command line. + +See `make help` for the list of the supported values. + +Setting "W=..." takes precedence over KBUILD_EXTRA_WARN. + KBUILD_DEBARCH -------------- For the deb-pkg target, allows overriding the normal heuristics deployed by @@ -241,11 +250,6 @@ To get all available archs you can also specify all. E.g.:: $ make ALLSOURCE_ARCHS=all tags -KBUILD_ENABLE_EXTRA_GCC_CHECKS ------------------------------- -If enabled over the make command line with "W=1", it turns on additional -gcc -W... options for more extensive build-time checking. - KBUILD_BUILD_TIMESTAMP ---------------------- Setting this to a date string overrides the timestamp used in the diff --git a/Makefile b/Makefile index 06e1e21c0f45..016d72eb3ddf 100644 --- a/Makefile +++ b/Makefile @@ -1538,7 +1538,7 @@ help: @echo ' make C=1 [targets] Check re-compiled c source with $$CHECK (sparse by default)' @echo ' make C=2 [targets] Force check of all c source with $$CHECK' @echo ' make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections' - @echo ' make W=n [targets] Enable extra gcc checks, n=1,2,3 where' + @echo ' make W=n [targets] Enable extra checks, n=1,2,3 where' @echo ' 1: warnings which may be relevant and do not occur too often' @echo ' 2: warnings which occur quite often but may still be relevant' @echo ' 3: more obscure warnings, can most likely be ignored' diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 2a21ca86b720..f72aba64d611 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -85,7 +85,7 @@ else ifeq ($(KBUILD_CHECKSRC),2) cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< endif -ifneq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),) +ifneq ($(KBUILD_EXTRA_WARN),) cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $< endif diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index d226c5fb13e2..53eb7e0c6a5a 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -8,14 +8,19 @@ KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned) +# backward compatibility +KBUILD_EXTRA_WARN ?= $(KBUILD_ENABLE_EXTRA_GCC_CHECKS) + ifeq ("$(origin W)", "command line") - export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W) + KBUILD_EXTRA_WARN := $(W) endif +export KBUILD_EXTRA_WARN + # # W=1 - warnings which may be relevant and do not occur too often # -ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter KBUILD_CFLAGS += -Wmissing-declarations @@ -48,7 +53,7 @@ endif # # W=2 - warnings which occur quite often but may still be relevant # -ifneq ($(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),) KBUILD_CFLAGS += -Wcast-align KBUILD_CFLAGS += -Wdisabled-optimization @@ -65,7 +70,7 @@ endif # # W=3 - more obscure warnings, can most likely be ignored # -ifneq ($(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifneq ($(findstring 3, $(KBUILD_EXTRA_WARN)),) KBUILD_CFLAGS += -Wbad-function-cast KBUILD_CFLAGS += -Wcast-qual diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 7ab17712ab24..df83967268ba 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -248,7 +248,7 @@ quiet_cmd_gzip = GZIP $@ DTC ?= $(objtree)/scripts/dtc/dtc # Disable noisy checks by default -ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),) DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-unit_address_format \ -Wno-avoid_unnecessary_addr_size \ @@ -259,7 +259,7 @@ DTC_FLAGS += -Wno-unit_address_vs_reg \ -Wno-pci_device_reg endif -ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),) DTC_FLAGS += -Wnode_name_chars_strict \ -Wproperty_name_chars_strict endif diff --git a/scripts/genksyms/Makefile b/scripts/genksyms/Makefile index baf44ed0a93a..78629f515e78 100644 --- a/scripts/genksyms/Makefile +++ b/scripts/genksyms/Makefile @@ -12,7 +12,7 @@ genksyms-objs := genksyms.o parse.tab.o lex.lex.o # # Just in case, run "$(YACC) --version" without suppressing stderr # so that 'bison: not found' will be displayed if it is missing. -ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) +ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),) quiet_cmd_bison_no_warn = $(quiet_cmd_bison) cmd_bison_no_warn = $(YACC) --version >/dev/null; \