From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754127AbaFYHOa (ORCPT ); Wed, 25 Jun 2014 03:14:30 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:47755 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751419AbaFYHO3 (ORCPT ); Wed, 25 Jun 2014 03:14:29 -0400 Date: Wed, 25 Jun 2014 09:14:16 +0200 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Guenter Roeck Cc: Ingo Molnar , Russell King , Peter Zijlstra , Benjamin Herrenschmidt , linux-kernel@vger.kernel.org, Ingo Molnar , Paul Mackerras , Vincent Guittot , linuxppc-dev@lists.ozlabs.org, Dietmar Eggemann , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2] sched: Fix compiler warnings Message-ID: <20140625071416.GM14781@pengutronix.de> References: <1403658329-13196-1-git-send-email-linux@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1403658329-13196-1-git-send-email-linux@roeck-us.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 2001:6f8:1178:2:5054:ff:fec0:8e10 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 24, 2014 at 06:05:29PM -0700, Guenter Roeck wrote: > Commit 143e1e28cb (sched: Rework sched_domain topology definition) > introduced a number of functions with a return value of 'const int'. > gcc doesn't know what to do with that and, if the kernel is compiled > with W=1, complains with the following warnings whenever sched.h > is included. > > include/linux/sched.h:875:25: warning: > type qualifiers ignored on function return type > include/linux/sched.h:882:25: warning: > type qualifiers ignored on function return type > include/linux/sched.h:889:25: warning: > type qualifiers ignored on function return type > include/linux/sched.h:1002:21: warning: > type qualifiers ignored on function return type > > Commits fb2aa855 (sched, ARM: Create a dedicated scheduler topology table) > and 607b45e9a (sched, powerpc: Create a dedicated topology table) introduce > the same warning in the arm and powerpc code. > > Drop 'const' from the function declarations to fix the problem. > > The fix for all three patches has to be applied together to avoid > compilation failures for the affected architectures. > > Cc: Dietmar Eggemann > Cc: Peter Zijlstra > Cc: Ingo Molnar > Cc: Benjamin Herrenschmidt > Cc: Vincent Guittot > Signed-off-by: Guenter Roeck > --- > v2: Fix problem in all affected architectures with a single patch > to avoid compilation errors. > > arch/arm/kernel/topology.c | 2 +- > arch/powerpc/kernel/smp.c | 2 +- > include/linux/sched.h | 8 ++++---- > 3 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c > index 9d85318..e35d880 100644 > --- a/arch/arm/kernel/topology.c > +++ b/arch/arm/kernel/topology.c > @@ -275,7 +275,7 @@ void store_cpu_topology(unsigned int cpuid) > cpu_topology[cpuid].socket_id, mpidr); > } > > -static inline const int cpu_corepower_flags(void) > +static inline int cpu_corepower_flags(void) > { > return SD_SHARE_PKG_RESOURCES | SD_SHARE_POWERDOMAIN; > } Maybe the author's intention was: static inline int cpu_corepower_flags(void) __attribute__((const)); ? This specifies that the function has no side effects and the return value only depends on the (here non-existing) function arguments. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |