From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754083Ab1L0N6B (ORCPT ); Tue, 27 Dec 2011 08:58:01 -0500 Received: from cantor2.suse.de ([195.135.220.15]:44761 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753894Ab1L0N57 (ORCPT ); Tue, 27 Dec 2011 08:57:59 -0500 Date: Tue, 27 Dec 2011 14:57:52 +0100 From: Michal Hocko To: "Kirill A. Shutemov" Cc: linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org, KAMEZAWA Hiroyuki , Balbir Singh , Johannes Weiner , Michal Marek , linux-kbuild@vger.kernel.org Subject: [PATCH] Makefiles: Disable unused-variable warning (was: Re: [PATCH 1/6] memcg: fix unused variable warning) Message-ID: <20111227135752.GK5344@tiehlicka.suse.cz> References: <1324695619-5537-1-git-send-email-kirill@shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1324695619-5537-1-git-send-email-kirill@shutemov.name> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat 24-12-11 05:00:14, Kirill A. Shutemov wrote: > From: "Kirill A. Shutemov" > > mm/memcontrol.c: In function ‘memcg_check_events’: > mm/memcontrol.c:784:22: warning: unused variable ‘do_numainfo’ [-Wunused-variable] > > Signed-off-by: Kirill A. Shutemov > --- > mm/memcontrol.c | 7 ++++--- > 1 files changed, 4 insertions(+), 3 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index d643bd6..a5e92bd 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -781,14 +781,15 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page) > /* threshold event is triggered in finer grain than soft limit */ > if (unlikely(mem_cgroup_event_ratelimit(memcg, > MEM_CGROUP_TARGET_THRESH))) { > - bool do_softlimit, do_numainfo; > + bool do_softlimit; > > - do_softlimit = mem_cgroup_event_ratelimit(memcg, > - MEM_CGROUP_TARGET_SOFTLIMIT); > #if MAX_NUMNODES > 1 > + bool do_numainfo; > do_numainfo = mem_cgroup_event_ratelimit(memcg, > MEM_CGROUP_TARGET_NUMAINFO); > #endif > + do_softlimit = mem_cgroup_event_ratelimit(memcg, > + MEM_CGROUP_TARGET_SOFTLIMIT); I don't like this very much. Maybe we should get rid of both do_* and do it with flags? But maybe it is not worth the additional code at all... Anyway, I am wondering why unused-but-set-variable is disabled while unused-variable is enabled. Shouldn't we just disable it as well rather than workaround this in the code? The warning is just pure noise in this case. What about something like: --- >>From e1136891fe86eacf9212b2144f80ff6b75b10194 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 27 Dec 2011 14:53:06 +0100 Subject: [PATCH] Makefiles: Disable unused-variable warning We are already disabling unused-but-set-variable and Wunused-variable produces some noise as well. Signed-off-by: Michal Hocko --- Makefile | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/Makefile b/Makefile index ea51081..25c76f3 100644 --- a/Makefile +++ b/Makefile @@ -578,6 +578,7 @@ endif # This warning generated too much noise in a regular build. # Use make W=1 to enable this warning (see scripts/Makefile.build) KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls -- 1.7.7.3 -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic