[Mesa-dev] [PATCH 4/9] configure.ac: define WL_HIDE_DEPRECATED at global scale

[Emil Velikov]

On 8 September 2017 at 10:52, Pekka Paalanen
<pekka.paalanen at collabora.co.uk> wrote:
> On Thu,  7 Sep 2017 19:05:01 +0100
> Emil Velikov <emil.l.velikov at gmail.com> wrote:
>
>> From: Emil Velikov <emil.velikov at collabora.com>
>>
>> Due to GCC feature described in previous commit, the expected
>> deprecation warnings may be missing.
>>
>> Set the WL_HIDE_DEPRECATED macro which will omit the deprecated
>> functionality, resulting in more distinct build issues.
>>
>> Patch is UNTESTED, see the open question below.
>>
>> Cc: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
>> Suggested-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
>> Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
>> ---
>> Pekka, I'm not 100% sold that having the macro all together is a good
>> idea. Consider the following example:
>>
>>  - Project X uses Wayland vY, set as min. requirement.
>>  - Project X sets the 'hide' macro
>>  - In nearly all cases, the check does not guard the upper version.
>>  - Wayland vY+Z, deprecates (and hides) functionality A
>>  - Project X fails to build against Wayland vY+Z
>
> Hi Emil,
>
> yes, that is exactly the problem of the macro: in reality, we cannot
> add more stuff under it. It was a one-shot macro, it has been used, and
> now the things it may hide have been carved in stone.
>
> If we want to hide more stuff in libwayland API in a similar way, we
> need a new macro per release or something.
>
> In any case, using WL_HIDE_DEPRECATED in Mesa and extending it to cover
> all code that deals with Wayland is a good thing, so:
> Acked-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
>
Smashing, thanks for the confirmation.
I'll send a patch to Wayland that documents things and adds a "don't
add stuff here" note ;-)

-Emil