From mboxrd@z Thu Jan  1 00:00:00 1970
From: "De Lara Guarch, Pablo" <pablo.de.lara.guarch@intel.com>
Subject: Re: [PATCH v2] examples/vhost: fix strict aliasing error
 on gcc 4.4.7
Date: Wed, 9 Dec 2015 10:52:35 +0000
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To: "Xie, Huawei" <huawei.xie@intel.com>, "dev@dpdk.org" <dev@dpdk.org>
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Hi Huawei,

> -----Original Message-----
> From: Xie, Huawei
> Sent: Wednesday, December 09, 2015 10:45 AM
> To: De Lara Guarch, Pablo; dev@dpdk.org
> Cc: yuanhan.liu@linux.intel.com
> Subject: Re: [PATCH v2] examples/vhost: fix strict aliasing error on gcc =
4.4.7
>=20
> On 12/9/2015 5:40 PM, De Lara Guarch, Pablo wrote:
> > From: "De Lara Guarch, Pablo" <pablo.de.lara.guarch@intel.com>
> >
> > Fixes following error on gcc 4.4.7:
> >
> > make: Entering directory `/tmp/dpdk-tmp/examples/vhost'
> >   CC main.o
> > cc1: warnings being treated as errors
> > /tmp/dpdk-tmp/examples/vhost/main.c: In function 'new_device':
> > /tmp/dpdk-tmp/x86_64-native-linuxapp-gcc/include/rte_ring.h:740:
> error:
> >     dereferencing pointer 'mbuf.486' does break strict-aliasing rules
> > /tmp/dpdk-tmp/examples/vhost/main.c:1503: note: initialized from here
> > ...
> > /tmp/dpdk-tmp/examples/vhost/main.c:1503: note: initialized from here
> > /tmp/dpdk-tmp/x86_64-native-linuxapp-gcc/include/rte_ring.h:740:
> error:
> >     dereferencing pointer '({anonymous})' does break strict-aliasing ru=
les
> > /tmp/dpdk-tmp/examples/vhost/main.c:1804: note: initialized from here
> > make[1]: *** [main.o] Error 1
> >
> > Fixes: d19533e8 ("examples/vhost: copy old vhost example")
> >
> > Reported-by: Qian Xu <qian.q.xu@intel.com>
> > Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
> Acked-by: Huawei Xie <huawei.xie@intel.com>
>=20

I am going to send a v3 for this patch, removing the other casting that Bru=
ce mentioned.
I will pre-ack it, unless you have any concerns.

Thanks,
Pablo