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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9300FC43219 for ; Wed, 9 Mar 2022 08:19:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231279AbiCIIUo (ORCPT ); Wed, 9 Mar 2022 03:20:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231264AbiCIIUc (ORCPT ); Wed, 9 Mar 2022 03:20:32 -0500 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4605140E50; Wed, 9 Mar 2022 00:19:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1646813973; x=1678349973; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=hLBK1t/r9Z48f8dSRNwh+u136IQEg0xMqQ5EbEwvT7Y=; b=aKgwPTuRF6SheFFJ7QFMCagcyzgbcXxjIk4ILwmEGg/0JAI96rN/B/pM ssCkOjdqlEkc1AN4981wf83bBycCVle+fcTWXAtezCd1OD45R5GlL1Vzt 8oB34dBAWdgXHB2r7RQjdPbNBm6xSGmKgRbQD9WsO3KznUVRUIjLzpU/k 7IYoKT3DTs3d2iDXO9/T1EruotchsJZxxzQuaAAbRjvZg/26m0C2Qa1qU DIlmYkgsJ3wOVwiKtEMg6g2GkRgGjvqGDFeV7yewjEqJxpI0E07TAg1yi md3eV6oYTk3a1+kRfrGXWtdyb6ZxEdgRlHEBTObtqN9bhq1BXF8P7my98 w==; X-IronPort-AV: E=McAfee;i="6200,9189,10280"; a="254649003" X-IronPort-AV: E=Sophos;i="5.90,167,1643702400"; d="scan'208";a="254649003" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Mar 2022 00:19:32 -0800 X-IronPort-AV: E=Sophos;i="5.90,167,1643702400"; d="scan'208";a="711860724" Received: from byrnec1x-mobl.ger.corp.intel.com (HELO localhost) ([10.252.29.235]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Mar 2022 00:19:27 -0800 From: Jani Nikula To: Arnd Bergmann , Masahiro Yamada Cc: alexs@kernel.org, arnd@arndb.de, arnd@kernel.org, dsterba@suse.com, elver@google.com, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, mark.rutland@arm.com, ndesaulniers@google.com, ojeda@kernel.org, torvalds@linux-foundation.org Subject: Re: [PATCH 1/4] [v4] Kbuild: add -Wno-shift-negative-value where -Wextra is used In-Reply-To: <20220308215615.14183-2-arnd@kernel.org> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20220308215615.14183-1-arnd@kernel.org> <20220308215615.14183-2-arnd@kernel.org> Date: Wed, 09 Mar 2022 10:19:25 +0200 Message-ID: <87ee3b1qsy.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 08 Mar 2022, Arnd Bergmann wrote: > From: Arnd Bergmann > > As a preparation for moving to -std=gnu11, turn off the > -Wshift-negative-value option. This warning is enabled by gcc when > building with -Wextra for c99 or higher, but not for c89. Since > the kernel already relies on well-defined overflow behavior, > the warning is not helpful and can simply be disabled in > all locations that use -Wextra. > > Signed-off-by: Arnd Bergmann Acked-by: Jani Nikula > --- > [v4] > split into a separate patch > --- > drivers/gpu/drm/i915/Makefile | 1 + > drivers/staging/greybus/tools/Makefile | 3 ++- > fs/btrfs/Makefile | 1 + > scripts/Makefile.extrawarn | 1 + > 4 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile > index 1b62b9f65196..1618a6e0af4e 100644 > --- a/drivers/gpu/drm/i915/Makefile > +++ b/drivers/gpu/drm/i915/Makefile > @@ -17,6 +17,7 @@ subdir-ccflags-y += -Wno-unused-parameter > subdir-ccflags-y += -Wno-type-limits > subdir-ccflags-y += -Wno-missing-field-initializers > subdir-ccflags-y += -Wno-sign-compare > +subdir-ccflags-y += -Wno-shift-negative-value > subdir-ccflags-y += $(call cc-disable-warning, unused-but-set-variable) > subdir-ccflags-y += $(call cc-disable-warning, frame-address) > subdir-ccflags-$(CONFIG_DRM_I915_WERROR) += -Werror > diff --git a/drivers/staging/greybus/tools/Makefile b/drivers/staging/greybus/tools/Makefile > index ad0ae8053b79..a3bbd73171f2 100644 > --- a/drivers/staging/greybus/tools/Makefile > +++ b/drivers/staging/greybus/tools/Makefile > @@ -12,7 +12,8 @@ CFLAGS += -std=gnu99 -Wall -Wextra -g \ > -Wredundant-decls \ > -Wcast-align \ > -Wsign-compare \ > - -Wno-missing-field-initializers > + -Wno-missing-field-initializers \ > + -Wno-shift-negative-value > > CC := $(CROSS_COMPILE)gcc > > diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile > index 4188ba3fd8c3..99f9995670ea 100644 > --- a/fs/btrfs/Makefile > +++ b/fs/btrfs/Makefile > @@ -17,6 +17,7 @@ subdir-ccflags-y += $(condflags) > subdir-ccflags-y += -Wno-missing-field-initializers > subdir-ccflags-y += -Wno-sign-compare > subdir-ccflags-y += -Wno-type-limits > +subdir-ccflags-y += -Wno-shift-negative-value > > obj-$(CONFIG_BTRFS_FS) := btrfs.o > > diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn > index 8be892887d71..650d0b8ceec3 100644 > --- a/scripts/Makefile.extrawarn > +++ b/scripts/Makefile.extrawarn > @@ -36,6 +36,7 @@ KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation) > KBUILD_CFLAGS += -Wno-missing-field-initializers > KBUILD_CFLAGS += -Wno-sign-compare > KBUILD_CFLAGS += -Wno-type-limits > +KBUILD_CFLAGS += -Wno-shift-negative-value > > KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1 -- Jani Nikula, Intel Open Source Graphics Center