Re: [PATCH v3 00/11] Fix build errors related to exported headers

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 7/8/2016 3:35 PM, Adrien Mazarguil wrote:
> On Fri, Jul 08, 2016 at 02:15:37PM +0000, Wiles, Keith wrote:
>>
>>> On Jul 8, 2016, at 4:56 AM, Yigit, Ferruh <ferruh.yigit@intel.com> wrote:
>>>
>>> On 7/8/2016 9:05 AM, Adrien Mazarguil wrote:
>>>> On Thu, Jul 07, 2016 at 06:33:17PM +0000, Wiles, Keith wrote:
>>>>>
>>>>>> On Jul 7, 2016, at 10:49 AM, Adrien Mazarguil <adrien.mazarguil@6wind.com> wrote:
>>>>>>
>>>>>> DPDK uses GNU C language extensions in most of its code base. This is fine
>>>>>> for internal source files whose compilation flags are controlled by DPDK,
>>>>>> however user applications that use exported "public" headers may experience
>>>>>> compilation failures when enabling strict error/standard checks (-std and
>>>>>> -pedantic for instance).
>>>>>
>>>>> Do you try compiling these changes with CLANG and/or ICC compilers?
>>>>
>>>> clang/clang++ yes, works fine. I did not try with ICC however.
>>>
>>> I tested with icc, getting following error [1], compiler warning seems
>>> valid, but didn't investigate what in your patch cause this.
>>>
>>> [1]
>>> .../app/test/test_table_acl.c(487): error #2405: array of elements
>>> containing a flexible array member is nonstandard
>>>                struct rte_pipeline_table_entry entries[5];
>>>                                                ^
>>>
>>> .../app/test/test_table_acl.c(492): error #2405: array of elements
>>> containing a flexible array member is nonstandard
>>>                struct rte_pipeline_table_entry entries_ptr[5];
>>
>> I am guessing it does not like the uint8_t action_data[0] in the rte_pipeline_table_entry structure. I can see why it would be non-standard allocated on the stack in this case. Maybe a keyword like __extension__ needs to be added or pragma.
> 
> Hmmm, right, a variable array cannot be embedded like that. I think a change
> in test_table_acl.c would be better.
Correct, I just wonder why not getting this same compiler warning before
your changes.

...

> Is that the only issue you saw?
> 
Yes.

>>>> Note that considering "({ ... })" is a GNU extension, compilers that do
>>>> support this syntax also support the GNU __extension__ keyword. As a result,
>>>> those that do not support this keyword most likely already cannot compile
>>>> DPDK at all.
>