From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 05F5D199AF for ; Fri, 6 Oct 2017 01:17:46 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Oct 2017 16:17:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.42,482,1500966000"; d="scan'208";a="907209491" Received: from unknown (HELO [10.241.225.33]) ([10.241.225.33]) by FMSMGA003.fm.intel.com with ESMTP; 05 Oct 2017 16:17:42 -0700 To: Olivier Matz , dev@dpdk.org, Yuanhan Liu , Maxime Coquelin References: <20170911151333.5727-1-olivier.matz@6wind.com> <20170911151333.5727-4-olivier.matz@6wind.com> From: Ferruh Yigit Message-ID: Date: Fri, 6 Oct 2017 00:17:41 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20170911151333.5727-4-olivier.matz@6wind.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [PATCH 03/10] net/virtio: fix compilation with -Og X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 05 Oct 2017 23:17:47 -0000 On 9/11/2017 4:13 PM, Olivier Matz wrote: > The compilation with gcc-6.3.0 and EXTRA_CFLAGS=-Og gives the following > error: > > CC virtio_rxtx.o > virtio_rxtx.c: In function ‘virtio_rx_offload’: > virtio_rxtx.c:680:10: error: ‘csum’ may be used uninitialized in > this function [-Werror=maybe-uninitialized] > csum = ~csum; > ~~~~~^~~~~~~ > > The function rte_raw_cksum_mbuf() may indeed return an error, and > in this case, csum won't be initialized. Fix it by initializing csum > to 0. After this fix if rte_raw_cksum_mbuf() returns error csum still will be wrong and since compiler warning suppressed it may be harder to find the root cause. For this case checking rte_raw_cksum_mbuf() return value seems better idea but I will cc the maintainer for decision. > > Fixes: 96cb6711939e ("net/virtio: support Rx checksum offload") > Signed-off-by: Olivier Matz > --- > drivers/net/virtio/virtio_rxtx.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c > index 45a9c919a..cab3a1675 100644 > --- a/drivers/net/virtio/virtio_rxtx.c > +++ b/drivers/net/virtio/virtio_rxtx.c > @@ -671,7 +671,7 @@ virtio_rx_offload(struct rte_mbuf *m, struct virtio_net_hdr *hdr) > * In case of SCTP, this will be wrong since it's a CRC > * but there's nothing we can do. > */ > - uint16_t csum, off; > + uint16_t csum = 0, off; > > rte_raw_cksum_mbuf(m, hdr->csum_start, > rte_pktmbuf_pkt_len(m) - hdr->csum_start, >