From patchwork Thu Jun 27 01:46:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 11018595 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D3ABE14E5 for ; Thu, 27 Jun 2019 01:47:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BBBC728981 for ; Thu, 27 Jun 2019 01:47:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AF60D28A2E; Thu, 27 Jun 2019 01:47:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A499428981 for ; Thu, 27 Jun 2019 01:47:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726811AbfF0BrZ (ORCPT ); Wed, 26 Jun 2019 21:47:25 -0400 Received: from conuserg-08.nifty.com ([210.131.2.75]:23029 "EHLO conuserg-08.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726801AbfF0BrY (ORCPT ); Wed, 26 Jun 2019 21:47:24 -0400 Received: from grover.flets-west.jp (softbank126125154139.bbtec.net [126.125.154.139]) (authenticated) by conuserg-08.nifty.com with ESMTP id x5R1kN0x032702; Thu, 27 Jun 2019 10:46:26 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-08.nifty.com x5R1kN0x032702 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1561599986; bh=IbQmIGA4DYqtLSrd9igtMcpMuk9jBtAXWel/GSOA8+0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T+qvoCg3RIgbgsavQ9zJThO28RX6JgBSu4vdMQ9gIBIDzi22uSj8ur9QVdAJiYLYn /mowYOiU3XKQKsTu8CcBe7y+6axgrrQ4tromLgTO/Yvpad88jrX+lThAD53n94k3jn Jzj57q06KTqDwDpXTvTJdIE6Ms53Y/nuoGh4QPJ6fORYejHft4hubFyXL5PY3ZtmOo HfFHnOOgiVfWtRiJO+tQWqs1IJPGuAkOhaTnTWFeiqENqNqfpgxY2KDwAW4j05zUvt WuVkKnj7cXl6NgkPN5O8BMe1YclL1M/+oLtp9LRE1wNsyNX6RQLg2kZ607gevXgYJH f032fFS3xI8zA== X-Nifty-SrcIP: [126.125.154.139] From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: Sam Ravnborg , Masahiro Yamada , linux-doc@vger.kernel.org, Jonathan Corbet , linux-kernel@vger.kernel.org, Michal Marek Subject: [PATCH v2 2/4] kbuild: do not create wrappers for header-test-y Date: Thu, 27 Jun 2019 10:46:15 +0900 Message-Id: <20190627014617.600-3-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190627014617.600-1-yamada.masahiro@socionext.com> References: <20190627014617.600-1-yamada.masahiro@socionext.com> Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP header-test-y does not work with headers in sub-directories. For example, you can write a Makefile, like this: include/linux/Kbuild: header-test-y += mtd/nand.h This entry creates a wrapper include/linux/mtd/nand.hdrtest.c with the following content: #include "mtd/nand.h" To make this work, we need to add $(srctree)/include/linux to the header search path. It would be tedious to add ccflags-y. We could change the *.hdrtest.c rule to wrap: #include "nand.h" This works for in-tree build since #include "..." searches in the relative path from the header with this directive. For O=... build, we need to add $(srctree)/include/linux/mtd to the header search path, which will be even more tedious. After all, I thought it would be handier to compile headers directly without creating wrappers. I added a new build rule to compile %.h into %.h.s I chose %.h.s instead of %.h.o because it was a little bit faster. Also, for GCC, an empty assembly is smaller than an empty object. I wrote the build rule: $(CC) $(c_flags) -S -o $@ -x c /dev/null -include $< instead of: $(CC) $(c_flags) -S -o $@ -x c $< Both work fine with GCC, but the latter is not good for Clang. This comes down to the difference in the -Wunused-function policy. GCC does not warn about unused 'static inline' functions at all. Clang does not warn about the ones in included headers, but does about the ones in the source. So, we should handle headers as headers, not as source files. In fact, this has been hidden since commit abb2ea7dfd82 ("compiler, clang: suppress warning for unused static inline functions"), but we should not rely on that. Signed-off-by: Masahiro Yamada Acked-by: Jani Nikula Tested-by: Jani Nikula --- Changes in v2: - New patch .gitignore | 1 - Documentation/dontdiff | 1 - Documentation/kbuild/makefiles.txt | 3 +-- Makefile | 1 - scripts/Makefile.build | 10 +++++----- scripts/Makefile.lib | 2 +- 6 files changed, 7 insertions(+), 11 deletions(-) diff --git a/.gitignore b/.gitignore index 4bb60f0fa23b..7587ef56b92d 100644 --- a/.gitignore +++ b/.gitignore @@ -22,7 +22,6 @@ *.elf *.gcno *.gz -*.hdrtest.c *.i *.ko *.lex.c diff --git a/Documentation/dontdiff b/Documentation/dontdiff index 554dfe4883d2..5eba889ea84d 100644 --- a/Documentation/dontdiff +++ b/Documentation/dontdiff @@ -19,7 +19,6 @@ *.grep *.grp *.gz -*.hdrtest.c *.html *.i *.jpeg diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index ca4b24ec0399..5080fec34609 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt @@ -1023,8 +1023,7 @@ When kbuild executes, the following steps are followed (roughly): header-test-y specifies headers (*.h) in the current directory that should be compile tested to ensure they are self-contained, i.e. compilable as standalone units. If CONFIG_HEADER_TEST is enabled, - this autogenerates dummy sources to include the headers, and builds them - as part of extra-y. + this builds them as part of extra-y. --- 6.7 Commands useful for building a boot image diff --git a/Makefile b/Makefile index f23516980796..7f293b0431fe 100644 --- a/Makefile +++ b/Makefile @@ -1648,7 +1648,6 @@ clean: $(clean-dirs) -o -name '*.dwo' -o -name '*.lst' \ -o -name '*.su' \ -o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \ - -o -name '*.hdrtest.c' \ -o -name '*.lex.c' -o -name '*.tab.[ch]' \ -o -name '*.asn1.[ch]' \ -o -name '*.symtypes' -o -name 'modules.order' \ diff --git a/scripts/Makefile.build b/scripts/Makefile.build index ee0319560513..776842b7e6a3 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -294,14 +294,14 @@ quiet_cmd_cc_lst_c = MKLST $@ $(obj)/%.lst: $(src)/%.c FORCE $(call if_changed_dep,cc_lst_c) -# Dummy C sources for header test (header-test-y target) +# header test (header-test-y target) # --------------------------------------------------------------------------- -quiet_cmd_header_test = HDRTEST $@ - cmd_header_test = echo "\#include \"$*.h\"" > $@ +quiet_cmd_cc_s_h = CC $@ + cmd_cc_s_h = $(CC) $(c_flags) -S -o $@ -x c /dev/null -include $< -$(obj)/%.hdrtest.c: - $(call cmd,header_test) +$(obj)/%.h.s: $(src)/%.h FORCE + $(call if_changed_dep,cc_s_h) # Compile assembler sources (.S) # --------------------------------------------------------------------------- diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 3e630fcaffd1..55ae1ec65342 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -67,7 +67,7 @@ extra-$(CONFIG_OF_ALL_DTBS) += $(patsubst %.dtb,%.dt.yaml, $(dtb-)) endif # Test self-contained headers -extra-$(CONFIG_HEADER_TEST) += $(patsubst %.h,%.hdrtest.o,$(header-test-y)) +extra-$(CONFIG_HEADER_TEST) += $(addsuffix .s, $(header-test-y)) # Add subdir path