From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?iso-8859-1?Q?N=E9lio?= Laranjeiro <nelio.laranjeiro@6wind.com>
Subject: Re: [PATCH v2] net/mlx5: return RSS hash result in mbuf
Date: Wed, 28 Sep 2016 09:01:13 +0200
Message-ID: <20160928070113.GJ32397@autoinstall.dev.6wind.com>
References: <cover.1473840791.git.nelio.laranjeiro@6wind.com>
 <30739c1ee245c3e3ee9a1122ca08285d718eb9b8.1474987853.git.nelio.laranjeiro@6wind.com>
 <4fbbd27b-9610-4772-5cba-5ce896b4eebf@intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 8bit
Cc: dev@dpdk.org, Bruce Richardson <bruce.richardson@intel.com>,
 Adrien Mazarguil <adrien.mazarguil@6wind.com>
To: Ferruh Yigit <ferruh.yigit@intel.com>
Return-path: <dev-bounces@dpdk.org>
Received: from mail-wm0-f47.google.com (mail-wm0-f47.google.com [74.125.82.47])
 by dpdk.org (Postfix) with ESMTP id DD4B72170
 for <dev@dpdk.org>; Wed, 28 Sep 2016 09:01:19 +0200 (CEST)
Received: by mail-wm0-f47.google.com with SMTP id w84so217458839wmg.1
 for <dev@dpdk.org>; Wed, 28 Sep 2016 00:01:19 -0700 (PDT)
Content-Disposition: inline
In-Reply-To: <4fbbd27b-9610-4772-5cba-5ce896b4eebf@intel.com>
List-Id: patches and discussions about DPDK <dev.dpdk.org>
List-Unsubscribe: <http://dpdk.org/ml/options/dev>,
 <mailto:dev-request@dpdk.org?subject=unsubscribe>
List-Archive: <http://dpdk.org/ml/archives/dev/>
List-Post: <mailto:dev@dpdk.org>
List-Help: <mailto:dev-request@dpdk.org?subject=help>
List-Subscribe: <http://dpdk.org/ml/listinfo/dev>,
 <mailto:dev-request@dpdk.org?subject=subscribe>
Errors-To: dev-bounces@dpdk.org
Sender: "dev" <dev-bounces@dpdk.org>

On Tue, Sep 27, 2016 at 06:03:51PM +0100, Ferruh Yigit wrote:
> On 9/27/2016 3:53 PM, Nelio Laranjeiro wrote:
> > Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
> 
> <...>
> 
> > @@ -1286,12 +1291,13 @@ mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
> >  		&(*rxq->cqes)[rxq->cq_ci & cqe_cnt].cqe64;
> >  	unsigned int i = 0;
> >  	unsigned int rq_ci = rxq->rq_ci << sges_n;
> > -	int len;
> >  
> >  	while (pkts_n) {
> >  		unsigned int idx = rq_ci & wqe_cnt;
> >  		volatile struct mlx5_wqe_data_seg *wqe = &(*rxq->wqes)[idx];
> >  		struct rte_mbuf *rep = (*rxq->elts)[idx];
> > +		int len;
> 
> clang generates following warning, -it is quite detailed compiler message:
> 
> .../drivers/net/mlx5/mlx5_rxtx.c:1327:7: error: variable 'len' is used
> uninitialized whenever 'if' condition is false
> [-Werror,-Wsometimes-uninitialized]
>                 if (!pkt) {
>                     ^~~~
> .../drivers/net/mlx5/mlx5_rxtx.c:1384:7: note: uninitialized use occurs here
>                 if (len > DATA_LEN(seg)) {
>                     ^~~
> .../drivers/net/mlx5/mlx5_rxtx.c:1327:3: note: remove the 'if' if its
> condition is always true
>                 if (!pkt) {
>                 ^~~~~~~~~~
> .../drivers/net/mlx5/mlx5_rxtx.c:1299:10: note: initialize the variable
> 'len' to silence this warning
>                 int len;
>                        ^
>                         = 0

Right, my version of clang don't report this error, the one from
ubuntu does.

I will fix it in a v3.

Thanks Ferruh,

-- 
Nélio Laranjeiro
6WIND