From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 34196241CB7; Thu, 9 Oct 2025 08:48:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759999739; cv=none; b=ZsDiRFJJ1CbVwUphlhMfN37ynbavjJqhvkmmF8WiFLokBtqjy/uo3WnExD54fOn5n/v0NAT6H8NhBEawDsWyDSMMd+PdVIjNDIZCTep7GaZxeyfWz4QXIdZsPQhU/KCM6ffHayqikz5Nz2lk9T5S6CQ07Hq9GoWZ6Bn8HH4n46k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759999739; c=relaxed/simple; bh=XcVzGEG7wl6bThfY5lOeGukSt2PGXHScZ9EbqkTi7js=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UJ1pVYi6ZupmW6+RlWn0ehP14rtLeFD+gKNoKmG9VqG0rGzAbz/gybmFb/tagGvN8QF0mPpnVD8xbk+Bk8qZ/qP87XcwcLUvsjPjlDhGiPSy0gn/QGTcodwACNeOcBO1x5BGtzUleNCP7w/CMv5nh5NGBtoKhId1sOIEmxyWiwk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=e2/7XxzM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="e2/7XxzM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41EAFC4CEE7; Thu, 9 Oct 2025 08:48:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1759999738; bh=XcVzGEG7wl6bThfY5lOeGukSt2PGXHScZ9EbqkTi7js=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e2/7XxzM1HLb+pyFzIpz+xZ0yy4SzrCmR7PDLo6q1mnriFsw1HUFajJmocPwXS5ZZ ZwbNoMLUWfNRG6i76FGSUpdGIsEllwR3JB/la68MYg2F3B6TAoqbwu90oMDLgNwJvb n5CJpL4FIqyV27qYqN/QYDPDYIexuMVMjaZxSJ5k7QbOJykcjKT1NA5hklrmFTASwP 5FIN6F0iWwPE9g7p+jffU+4BEKaoh+eEcFXGMpuwYMRE1rlIObNag63WaFsxK10IdX 7sMkSAm5BVR4Z4+JiswasTUIe7DmJT4spXt8LRlO+Kgx3ZsFEMPVuFVQZiM6SzRlp9 muaHoPZlQEiKA== Date: Thu, 9 Oct 2025 10:48:45 +0200 From: Nicolas Schier To: Askar Safin Cc: linux-kbuild@vger.kernel.org, Masahiro Yamada , regressions@lists.linux.dev, nathan@kernel.org, linux-kernel@vger.kernel.org, miguel.ojeda.sandonis@gmail.com, ojeda@kernel.org, sam@gentoo.org, thomas.weissschuh@linutronix.de, Daniel Xu Subject: Re: [REGRESSION][BISECTED] kbuild: CFLAGS=-w no longer works Message-ID: References: <20251009075149.1083040-1-safinaskar@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251009075149.1083040-1-safinaskar@gmail.com> On Thu, Oct 09, 2025 at 10:51:49AM +0300, Askar Safin wrote: > #regzbot introduced: d1d0963121769d8d16150b913fe886e48efefa51 > > As well as I understand, if you want to disable warnings, you > should pass "CFLAGS=-w" to "make". Starting with d1d096312176, > this no longer works. > > Steps to reproduce: > > $ cd linux > $ git clean -f -q -d -x # To clean everything not controlled by git > $ echo 'CONFIG_64BIT=y' > /tmp/minimini > $ make allnoconfig KCONFIG_ALLCONFIG=/tmp/minimini > $ make -j32 CFLAGS=-w If you want to hand-over additional CFLAGS to kbuild you need to use KCFLAGS or other variations, see Documentation/kbuild/kbuild.rst. When I intentionally introduce a warning in e.g. init/main.c, I can suppress the compiler warning by calling make KCFLAGS=-w Your log output below does not contain any warning, so I assume that you actually want to point to something different. [...] > CC /rbt/linux/tools/objtool/libsubcmd/exec-cmd.o > CC /rbt/linux/tools/objtool/libsubcmd/help.o > CC /rbt/linux/tools/objtool/libsubcmd/pager.o > CC /rbt/linux/tools/objtool/libsubcmd/parse-options.o > CC /rbt/linux/tools/objtool/libsubcmd/run-command.o > CC /rbt/linux/tools/objtool/libsubcmd/sigchain.o > CC /rbt/linux/tools/objtool/libsubcmd/subcmd-config.o > exec-cmd.c:2:10: fatal error: linux/compiler.h: No such file or directory > 2 | #include > | ^~~~~~~~~~~~~~~~~~ > compilation terminated. > make[5]: *** [/rbt/linux/tools/build/Makefile.build:86: /rbt/linux/tools/objtool/libsubcmd/exec-cmd.o] Error 1 > make[5]: *** Waiting for unfinished jobs.... > parse-options.c:2:10: fatal error: linux/compiler.h: No such file or directory > 2 | #include > | ^~~~~~~~~~~~~~~~~~ > compilation terminated. > make[5]: *** [/rbt/linux/tools/build/Makefile.build:86: /rbt/linux/tools/objtool/libsubcmd/parse-options.o] Error 1 > In file included from sigchain.c:3: > subcmd-util.h:8:10: fatal error: linux/compiler.h: No such file or directory > 8 | #include > | ^~~~~~~~~~~~~~~~~~ > compilation terminated. > make[5]: *** [/rbt/linux/tools/build/Makefile.build:86: /rbt/linux/tools/objtool/libsubcmd/sigchain.o] Error 1 > MKELF scripts/mod/elfconfig.h > In file included from help.c:12: > subcmd-util.h:8:10: fatal error: linux/compiler.h: No such file or directory > 8 | #include > | ^~~~~~~~~~~~~~~~~~ > compilation terminated. > HOSTCC scripts/mod/modpost.o > make[5]: *** [/rbt/linux/tools/build/Makefile.build:85: /rbt/linux/tools/objtool/libsubcmd/help.o] Error 1 > HOSTCC scripts/mod/sumversion.o > In file included from run-command.c:11: > subcmd-util.h:8:10: fatal error: linux/compiler.h: No such file or directory > 8 | #include > | ^~~~~~~~~~~~~~~~~~ > compilation terminated. > HOSTCC scripts/mod/symsearch.o > make[5]: *** [/rbt/linux/tools/build/Makefile.build:85: /rbt/linux/tools/objtool/libsubcmd/run-command.o] Error 1 > UPD scripts/mod/devicetable-offsets.h > HOSTCC scripts/mod/file2alias.o > make[4]: *** [Makefile:78: /rbt/linux/tools/objtool/libsubcmd/libsubcmd-in.o] Error 2 > make[3]: *** [Makefile:83: /rbt/linux/tools/objtool/libsubcmd/libsubcmd.a] Error 2 > make[2]: *** [Makefile:73: objtool] Error 2 > make[1]: *** [/rbt/linux/Makefile:1430: tools/objtool] Error 2 > make[1]: *** Waiting for unfinished jobs.... This is reproducible on my machine: make -C tools objtool CFLAGS=-w But is doesn't matter which CFLAGS you add here, as they overwrite objtool's include paths. According to tools/build/Documentation/Build.txt you should use different variables for everything below tools/, e.g.: make -C tools objtool CFLAGS_objtool=-w Does this help for your specific issue? Kind regards, Nicolas