From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3.mail.elte.hu (mx3.mail.elte.hu [157.181.1.138]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id E559DDDEFD for ; Fri, 17 Oct 2008 22:10:10 +1100 (EST) Date: Fri, 17 Oct 2008 13:09:45 +0200 From: Ingo Molnar To: David Miller Subject: Re: powerpc allmodconfig Message-ID: <20081017110945.GA32364@elte.hu> References: <20081015213337.a99a9595.akpm@linux-foundation.org> <20081015.220247.262683261.davem@davemloft.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <20081015.220247.262683261.davem@davemloft.net> Cc: bzolnier@gmail.com, marek.vasut@gmail.com, tiwai@suse.de, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, ralf@linux-mips.org, mark.fasheh@oracle.com, linuxppc-dev@ozlabs.org, linux-ide@vger.kernel.org, akpm@linux-foundation.org, linux-ext4@vger.kernel.org, dwmw2@infradead.org, dan.j.williams@intel.com, mchehab@infradead.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , * David Miller wrote: > > net/dccp/options.c: In function 'dccp_parse_options': > > net/dccp/options.c:67: warning: 'value' may be used uninitialized in > > this function > > Known issue, not trivial to fix, gcc is just being incredibly silly > here as it can't see all of the control flow. i just ran into this - do you have any objection against the patch below? Should we have a cleaner annotation perhaps instead of uninitialized_var()? Something like: #define __used __attribute__((used)) ? Ingo ----------> >>From d917af0bd043eab40d57f79cba9cf7a7b265a205 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 17 Oct 2008 12:41:30 +0200 Subject: [PATCH] fix warning in net/dccp/options.c MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit fix this warning: net/dccp/options.c: In function ‘dccp_parse_options’: net/dccp/options.c:67: warning: ‘value’ may be used uninitialized in this function This is a bogus GCC warning. The compiler does not recognize the relation between "value" and "mandatory" variables: the code flow can ever reach the "out_invalid_option:" label if 'mandatory' is set to 1, and when 'mandatory' is non-zero, we'll always have 'value' initialized. Help out the compiler by annotating the variable. Signed-off-by: Ingo Molnar --- net/dccp/options.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/dccp/options.c b/net/dccp/options.c index 0809b63..18dcfb9 100644 --- a/net/dccp/options.c +++ b/net/dccp/options.c @@ -64,7 +64,7 @@ int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, (dh->dccph_doff * 4); struct dccp_options_received *opt_recv = &dp->dccps_options_received; unsigned char opt, len; - unsigned char *value; + unsigned char *uninitialized_var(value); u32 elapsed_time; __be32 opt_val; int rc;