i40e: fix build with some toolchains

Compile warning which is treated as error occurs on Oracle Linux
(kernel 2.6.39, gcc 4.4.7) as below, or RHEL, CentOS. Aliasing
'struct i40e_aqc_debug_reg_read_write' should be avoided. Use the
elements inside that structure directly can fix the issue.

lib/librte_pmd_i40e/i40e_ethdev.c: In function 'eth_i40e_dev_init':
lib/librte_pmd_i40e/i40e_ethdev.c:5318: error: dereferencing pointer
  'cmd' does break strict-aliasing rules
lib/librte_pmd_i40e/i40e_ethdev.c:5314: note: initialized from here

Signed-off-by: Helin Zhang <helin.zhang@intel.com>

diff --git a/lib/librte_pmd_i40e/i40e_ethdev.c b/lib/librte_pmd_i40e/i40e_ethdev.c
index 624f0ce..b47a3d2 100644 (file)
--- a/lib/librte_pmd_i40e/i40e_ethdev.c
+++ b/lib/librte_pmd_i40e/i40e_ethdev.c
@@ -5310,18 +5310,17 @@ static int
 i40e_debug_read_register(struct i40e_hw *hw, uint32_t addr, uint64_t *val)
 {
        struct i40e_aq_desc desc;
-       struct i40e_aqc_debug_reg_read_write *cmd =
-               (struct i40e_aqc_debug_reg_read_write *)&desc.params.raw;
        enum i40e_status_code status;
 
        i40e_fill_default_direct_cmd_desc(&desc, i40e_aqc_opc_debug_read_reg);
-       cmd->address = rte_cpu_to_le_32(addr);
+       desc.params.internal.param1 = rte_cpu_to_le_32(addr);
        status = i40e_asq_send_command(hw, &desc, NULL, 0, NULL);
        if (status < 0)
                return status;
 
-       *val = ((uint64_t)(rte_le_to_cpu_32(cmd->value_high)) << (CHAR_BIT *
-                       sizeof(uint32_t))) + rte_le_to_cpu_32(cmd->value_low);
+       *val = ((uint64_t)(rte_le_to_cpu_32(desc.params.internal.param2)) <<
+                                       (CHAR_BIT * sizeof(uint32_t))) +
+                               rte_le_to_cpu_32(desc.params.internal.param3);
 
        return status;
 }