>Hi,
>
>On 04/14/2016 05:33 PM, Wiles, Keith wrote:
>>>
>>> static void
>>> -txq_mp2mr_mbuf_check(void *arg, void *start, void *end,
>>> - uint32_t index __rte_unused)
>>> +txq_mp2mr_mbuf_check(struct rte_mempool *mp, void *arg, void *obj,
>>> + __rte_unused uint32_t index)
>>
>> I have seen this use of __rte_unused or attributes attached to variables and
>> structures in couple different ways.
>>
>> I have seen the placement of the attribute after and before the variable I
>> prefer the attribute to be after, but could adapt I hope.
>> Do we have a rule about where the attribute is put in this case and others.
>> I have seen the attributes for structures are always at the end of the
>> structure, which is some cases it may not compile in other places.
>>
>> I would like to suggest we place the attributes at the end of structure e.g.
>> __rte_cached_aligned and I would like to see the __rte_unused after the
>> variable as a style in the code.
>
>I agree the __rte_unused shouldn't have moved in this patch.
>
>About the default place of attributes, I've seen an exemple where
>putting it at the end didn't what I expected:
>
> struct {
> int foo;
> } __rte_cache_aligned;
>
>The expected behavior is to define a structure which is cache aligned.
>But if "rte_memory.h" is not included, it will define a structure which
>is not cache aligned, and a global variable called __rte_cache_aligned,
>without any compiler warning.
>
>The gcc doc gives some hints about where to place the attributes:
>https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html
Then I suggest we start using the suggested syntax in the above link.
I did a quick read of the text and did not see where the above unused would be
placed, did someone find it?
>
>Given its length, I'm not sure the dpdk coding rules should contain
>anything more than "refer to gcc documentation" ;)
>
>Regards,
>Olivier
>
Regards,
Keith
