[dpdk-dev] i40e: fix the build error with gcc 4.4

  Fix the build warning reported like:
   error: dereferencing pointer 'cmd' does break strict-aliasing rules

Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
---
 drivers/net/i40e/i40e_ethdev.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)
  

Hi,

> -----Original Message-----
> From: Wu, Jingjing
> Sent: Wednesday, July 8, 2015 2:37 PM
> To: dev@dpdk.org
> Cc: Wu, Jingjing; Lu, Wenzhuo
> Subject: [PATCH] i40e: fix the build error with gcc 4.4
> 
> Fix the build warning reported like:
>    error: dereferencing pointer 'cmd' does break strict-aliasing rules
> 
> Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>

> ---
>  drivers/net/i40e/i40e_ethdev.c | 27 ++++++++++++++-------------
>  1 file changed, 14 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 02d17b4..dcf91bb 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -5786,8 +5786,7 @@ i40e_aq_add_mirror_rule(struct i40e_hw *hw,
>  			uint16_t count, uint16_t *rule_id)
>  {
>  	struct i40e_aq_desc desc;
> -	struct i40e_aqc_add_delete_mirror_rule *cmd =
> -		(struct i40e_aqc_add_delete_mirror_rule *)&desc.params.raw;
> +	struct i40e_aqc_add_delete_mirror_rule cmd;
>  	struct i40e_aqc_add_delete_mirror_rule_completion *resp =
>  		(struct i40e_aqc_add_delete_mirror_rule_completion *)
>  		&desc.params.raw;
> @@ -5796,18 +5795,20 @@ i40e_aq_add_mirror_rule(struct i40e_hw *hw,
> 
>  	i40e_fill_default_direct_cmd_desc(&desc,
>  					  i40e_aqc_opc_add_mirror_rule);
> +	memset(&cmd, 0, sizeof(cmd));
> 
>  	buff_len = sizeof(uint16_t) * count;
>  	desc.datalen = rte_cpu_to_le_16(buff_len);
>  	if (buff_len > 0)
>  		desc.flags |= rte_cpu_to_le_16(
>  			(uint16_t)(I40E_AQ_FLAG_BUF | I40E_AQ_FLAG_RD));
> -	cmd->rule_type = rte_cpu_to_le_16(rule_type <<
> +	cmd.rule_type = rte_cpu_to_le_16(rule_type <<
>  				I40E_AQC_MIRROR_RULE_TYPE_SHIFT);
> -	cmd->num_entries = rte_cpu_to_le_16(count);
> -	cmd->seid = rte_cpu_to_le_16(seid);
> -	cmd->destination = rte_cpu_to_le_16(dst_id);
> +	cmd.num_entries = rte_cpu_to_le_16(count);
> +	cmd.seid = rte_cpu_to_le_16(seid);
> +	cmd.destination = rte_cpu_to_le_16(dst_id);
> 
> +	rte_memcpy(&desc.params.raw, &cmd, sizeof(cmd));
>  	status = i40e_asq_send_command(hw, &desc, entries, buff_len, NULL);
>  	PMD_DRV_LOG(INFO, "i40e_aq_add_mirror_rule, aq_status %d,"
>  			 "rule_id = %u"
> @@ -5836,30 +5837,30 @@ i40e_aq_del_mirror_rule(struct i40e_hw *hw,
>  		uint16_t count, uint16_t rule_id)
>  {
>  	struct i40e_aq_desc desc;
> -	struct i40e_aqc_add_delete_mirror_rule *cmd =
> -		(struct i40e_aqc_add_delete_mirror_rule *)&desc.params.raw;
> +	struct i40e_aqc_add_delete_mirror_rule cmd;
>  	uint16_t buff_len = 0;
>  	enum i40e_status_code status;
>  	void *buff = NULL;
> 
>  	i40e_fill_default_direct_cmd_desc(&desc,
>  					  i40e_aqc_opc_delete_mirror_rule);
> -
> +	memset(&cmd, 0, sizeof(cmd));
>  	if (rule_type == I40E_AQC_MIRROR_RULE_TYPE_VLAN) {
>  		desc.flags |= rte_cpu_to_le_16((uint16_t)(I40E_AQ_FLAG_BUF
> |
>  							  I40E_AQ_FLAG_RD));
> -		cmd->num_entries = count;
> +		cmd.num_entries = count;
>  		buff_len = sizeof(uint16_t) * count;
>  		desc.datalen = rte_cpu_to_le_16(buff_len);
>  		buff = (void *)entries;
>  	} else
>  		/* rule id is filled in destination field for deleting mirror rule */
> -		cmd->destination = rte_cpu_to_le_16(rule_id);
> +		cmd.destination = rte_cpu_to_le_16(rule_id);
> 
> -	cmd->rule_type = rte_cpu_to_le_16(rule_type <<
> +	cmd.rule_type = rte_cpu_to_le_16(rule_type <<
>  				I40E_AQC_MIRROR_RULE_TYPE_SHIFT);
> -	cmd->seid = rte_cpu_to_le_16(seid);
> +	cmd.seid = rte_cpu_to_le_16(seid);
> 
> +	rte_memcpy(&desc.params.raw, &cmd, sizeof(cmd));
>  	status = i40e_asq_send_command(hw, &desc, buff, buff_len, NULL);
> 
>  	return status;
> --
> 1.9.3
  

> > Fix the build warning reported like:
> >    error: dereferencing pointer 'cmd' does break strict-aliasing rules
> > 
> > Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
> Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>

Fixes: a4def5edf0fc ("i40e: enable port mirroring")

Applied, thanks