From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752305Ab0CRUDj (ORCPT ); Thu, 18 Mar 2010 16:03:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33593 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751810Ab0CRUDh (ORCPT ); Thu, 18 Mar 2010 16:03:37 -0400 Message-ID: <4BA28708.3080705@redhat.com> Date: Thu, 18 Mar 2010 16:03:20 -0400 From: Masami Hiramatsu User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.8) Gecko/20100301 Fedora/3.0.3-1.fc11 Thunderbird/3.0.3 MIME-Version: 1.0 To: mingo@redhat.com, hpa@zytor.com, acme@redhat.com, paulus@samba.org, linux-kernel@vger.kernel.org, fweisbec@gmail.com, a.p.zijlstra@chello.nl, efault@gmx.de, tglx@linutronix.de, mhiramat@redhat.com, mingo@elte.hu CC: linux-tip-commits@vger.kernel.org Subject: Re: [tip:perf/core] perf events: Fix false positive build warning with older GCC's References: <20100316220612.32050.33806.stgit@localhost6.localdomain6> In-Reply-To: X-Enigmail-Version: 1.0.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org tip-bot for Ingo Molnar wrote: > Commit-ID: 55632770d7298835645489828af87f854c47749c > Gitweb: http://git.kernel.org/tip/55632770d7298835645489828af87f854c47749c > Author: Ingo Molnar > AuthorDate: Thu, 18 Mar 2010 16:51:16 +0100 > Committer: Ingo Molnar > CommitDate: Thu, 18 Mar 2010 17:03:24 +0100 > > perf events: Fix false positive build warning with older GCC's > > gcc 4.2.1 produces: > > util/probe-event.c: In function 'add_perf_probe_events': > util/probe-event.c:883: warning: 'tev' may be used uninitialized in this function > make: *** [util/probe-event.o] Error 1 > > Newer GCCs get this right. > > To work it around, initialize the variable to NULL so that older GCCs see > it as initialized too. Hmm, indeed. this code implies that ntevs > 0, it seems that we'd better check it first (e.g. 'if(ntevs <= 0) return;') too. Thank you, > > Cc: Masami Hiramatsu > Cc: Frederic Weisbecker > Cc: Arnaldo Carvalho de Melo > Cc: Paul Mackerras > Cc: Mike Galbraith > Cc: Peter Zijlstra > LKML-Reference: <20100316220612.32050.33806.stgit@localhost6.localdomain6> > Signed-off-by: Ingo Molnar > --- > tools/perf/util/probe-event.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c > index f333269..c6603f3 100644 > --- a/tools/perf/util/probe-event.c > +++ b/tools/perf/util/probe-event.c > @@ -880,7 +880,7 @@ static void __add_kprobe_trace_events(struct perf_probe_event *pev, > int ntevs, bool allow_suffix) > { > int i, fd; > - struct kprobe_trace_event *tev; > + struct kprobe_trace_event *tev = NULL; > char buf[64]; > const char *event, *group; > struct strlist *namelist; > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- Masami Hiramatsu e-mail: mhiramat@redhat.com