[waffle] [PATCH] wflinfo: Fix MSVC compilation error.

[Emil Velikov]

On 4 February 2015 at 15:12, Jose Fonseca <jfonseca at vmware.com> wrote:
> On 30/01/15 22:21, Emil Velikov wrote:
>>
>> On 30/01/15 20:02, Jose Fonseca wrote:
>>>
>>> On 30/01/15 16:25, Emil Velikov wrote:
>>>>
>>>> On 30 January 2015 at 11:07, Jose Fonseca <jfonseca at vmware.com> wrote:
>>>>>
>>>>> Workaround what seems to be a bug in MSVC parser for C99.
>>>>>
>>>>>
>>>>> https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.freedesktop.org_archives_waffle_2015-2DJanuary_000975.html&d=AwIBaQ&c=Sqcl0Ez6M0X8aeM67LKIiDJAXVeAw-YihVMNtXt-uEs&r=zfmBZnnVGHeYde45pMKNnVyzeaZbdIqVLprmZCM2zzE&m=EOTSIhn-7yCkuKuQ-JCDhS7EtrWFaozBDxo228XaWso&s=0Bi5_OB7Grl7-w1RO8R0l0YtCyi9IkRu-lB9Jtt7Ono&e=
>>>>>
>>>> Should have spotted this a Frank sent out the patch. Sorry about this
>>>> Jose.
>>>> Reviewed-by: Emil Velikov <emil.l.velikov at gmail.com>
>>>>
>>>> Wondering if we should (as a follow up commit) move the variable
>>>> declarations prior to the code to avoid such fun in the future ?
>>>
>>>
>>> It's hard to say.
>>>
>>> It looks like MSVC allows declarations in the middle of blocks, but the
>>> parser gets into a wierd state some times.
>>>
>>  From my earlier experience this issue happens as the variable type is a
>> typedef or a struct. For simple types such as int, float, etc. I've not
>> seen such problems. Or was it when the declaration is initialised
>> (with/wo a designated initializer) ?
>>
>>> I think the surer way long term would be to report the MSVC bug to
>>> Microsoft.  There have been positive experiences in the past [1] [2]
>>>
>> Good point. I'll put it on my list but I don't even have an live/msdn
>> account :\ I'm not sure when I'll get around to creating one, so if
>> anyone is interested the following mock-up should be able to visualise
>> the problem(s).
>>
>>
>> #include <stdio.h>
>> #include <stdlib.h>
>>
>> struct foo {
>>     int i;
>> };
>>
>> typedef int bar;
>>
>> int
>> main(void)
>> {
>>     struct foo foo1 = { .i = 1 };
>>     printf("foo1 %d\n", foo1.i);
>> // ^^
>> // The preprocessor/compiler will throw an error here.
>>
>>     struct foo foo2 = { .i = 2 };
>>     printf("foo2 %d\n", foo2.i);
>> // ^^
>> // The preprocessor/compiler will throw an error here.
>>
>>     bar bar1 = 1;
>>     printf("bar1 %d\n", bar1);
>>
>>     return 0;
>> }
>>
>>
>> Cheers,
>> Emil
>
>
> Thanks for isolating a test case Emil.
>
> I have good news: MSVC 2013 Update 4 seems to have fixed the issue, so we
> don't need to file a bug after all.
>
> Given that waffle requires C99, it basically requires MSVC 2013.  And given
> that MSVC 2013 U4 is a free update it seems acceptable to require it too.
> (This is what I'm proposing for piglit too BTW)
>
Great news Jose. I will send a patch for waffle that updates the cmake
+ readme file.

Huge thanks for the update.
Emil