> -----Original Message-----
> From: Yigit, Ferruh
> Sent: Wednesday, July 04, 2018 5:52 PM
> To: Liu, Yong <yong....@intel.com>; maxime.coque...@redhat.com
> Cc: dev@dpdk.org; Bie, Tiwei <tiwei....@intel.com>
> Subject: Re: [PATCH] net/virtio: fix build with gcc optimization on
>
> On 7/4/2018 11:56 AM, Marvin Liu wrote:
> > build error on gcc version 8.1.1 20180502 (Red Hat 8.1.1-1),
> > with optimization level >= O2
> >
> > .../drivers/net/virtio/virtio_rxtx.c:
> > In function ‘virtio_xmit_cleanup_inorder’:
> > .../drivers/net/virtio/virtio_rxtx.c:195:24:
> > error: ‘desc_idx’ may be used uninitialized in this function
> > [-Werror=maybe-uninitialized]
> > uint16_t i, used_idx, desc_idx, last_idx;
> > ^~~~~~~~
> > Optimization option fcode-hoisting will cause error on gcc 8.x.x.
> > Initialize desc_idx before using can fix build error.
> >
> > Fixes: e3851816e63c ("net/virtio: support in-order Rx and Tx")
> >
> > Reported-by: Ferruh Yigit <ferruh.yi...@intel.com>
> > Signed-off-by: Marvin Liu <yong....@intel.com>
>
> Hi Marvin,
>
> Sorry if this was not clear, I already did the update while merging the
> patch in
> next-net [1]. Can you please check the latest code in next-net?
>
> [1]
> ...
> 193 virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num)
> 194 {
> 195 uint16_t i, used_idx, desc_idx = 0, last_idx;
> ...
>
Ferruh, the latest code in next-net can build pass. You can ignore this patch.
> >
> > diff --git a/drivers/net/virtio/virtio_rxtx.c
> b/drivers/net/virtio/virtio_rxtx.c
> > index 6394071b8..19beb4bf4 100644
> > --- a/drivers/net/virtio/virtio_rxtx.c
> > +++ b/drivers/net/virtio/virtio_rxtx.c
> > @@ -192,7 +192,8 @@ virtio_xmit_cleanup(struct virtqueue *vq, uint16_t
> num)
> > static void
> > virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num)
> > {
> > - uint16_t i, used_idx, desc_idx, last_idx;
> > + uint16_t i, used_idx, last_idx;
> > + uint16_t desc_idx = 0;
> > int16_t free_cnt = 0;
> > struct vq_desc_extra *dxp = NULL;
> >
> >
