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 775EAC001B5 for ; Fri, 2 Sep 2022 16:30:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234698AbiIBQas (ORCPT ); Fri, 2 Sep 2022 12:30:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235962AbiIBQan (ORCPT ); Fri, 2 Sep 2022 12:30:43 -0400 Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A99F386885 for ; Fri, 2 Sep 2022 09:30:38 -0700 (PDT) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 282GRT1B016993; Fri, 2 Sep 2022 11:27:29 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 282GRS0W016992; Fri, 2 Sep 2022 11:27:28 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Fri, 2 Sep 2022 11:27:28 -0500 From: Segher Boessenkool To: Nathan Chancellor Cc: Christophe Leroy , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Nicholas Piggin Subject: Re: [PATCH v2 2/2] powerpc/math-emu: Remove -w build flag and fix warnings Message-ID: <20220902162728.GS25951@gate.crashing.org> References: <35c86b7ca823954c6cd593acc3690dc3748da9b1.1662113301.git.christophe.leroy@csgroup.eu> <20220902155954.GP25951@gate.crashing.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! On Fri, Sep 02, 2022 at 09:11:48AM -0700, Nathan Chancellor wrote: > On Fri, Sep 02, 2022 at 10:59:54AM -0500, Segher Boessenkool wrote: > > Maybe add -Wno-implicit-fallthrough? This code is a copy from outside > > the kernel, no one has ever wanted to maintain it, if nothing else (the > > more politically correct formulation is "we cannot as easily pick up > > improvements from upstream if we modify stuff"). > > Sure, we could do something like this if you preferred: > > diff --git a/arch/powerpc/math-emu/Makefile b/arch/powerpc/math-emu/Makefile > index 26fef2e5672e..ed775747a2a5 100644 > --- a/arch/powerpc/math-emu/Makefile > +++ b/arch/powerpc/math-emu/Makefile > @@ -16,3 +16,7 @@ obj-$(CONFIG_SPE) += math_efp.o > > CFLAGS_fabs.o = -fno-builtin-fabs > CFLAGS_math.o = -fno-builtin-fabs > + > +ifdef CONFIG_CC_IS_CLANG > +ccflags-remove-y := $(CONFIG_CC_IMPLICIT_FALLTHROUGH) > +endif That is a GCC warning as well. It needs some $(call cc-option ...) thing then, though (GCC versions of more than two or so years ago are supported as well). > At the same time, I see other modifications to these files that appear > to be for the kernel only so I suspect that this is already in the "we > cannot as easily pick up improvements from upstream" category, > regardless of that diff. So maybe someone should really maintain this stuff, bring it up to some reasonably modern state? :-) Segher