[Mesa-dev] [PATCH 2/4] mesa: drop APPLE_vertex_array_object support

[Timothy Arceri]

On 16/05/17 23:26, Emil Velikov wrote:
> On 16 May 2017 at 02:07, Timothy Arceri <tarceri at itsqueeze.com> wrote:
>> On 16/05/17 10:47, Kenneth Graunke wrote:
>>>
>>> On Monday, May 15, 2017 4:06:31 PM PDT Timothy Arceri wrote:
>>>>
>>>> On 16/05/17 08:13, Ian Romanick wrote:
>>>>>
>>>>> On 04/23/2017 10:28 PM, Timothy Arceri wrote:
>>>>>
>>>>>> diff --git a/src/mapi/glapi/gen/APPLE_vertex_array_object.xml
>>>>>> b/src/mapi/glapi/gen/APPLE_vertex_array_object.xml
>>>>>> deleted file mode 100644
>>>>>> index 7312f9b..0000000
>>>>>> --- a/src/mapi/glapi/gen/APPLE_vertex_array_object.xml
>>>>>> +++ /dev/null
>>>>>> @@ -1,27 +0,0 @@
>>>>>
>>>>>
>>>>>
>>>>> So... I'm fairly sure this is going to break loading a _dri.so built
>>>>> without this patch by a libGL built with this patch.
>>>>
>>>>
>>>> I recall something like this coming up a few year ago, can you remind me
>>>> again why this is a problem? Shouldn't these be updated in sync?
>>>
>>>
>>> Out-of-tree drivers, such as the legacy DRI1 drivers, won't be updated
>>> in sync (or likely ever).  I believe there are also at least two closed
>>> source drivers (though that isn't a good reason not to do this change).
> Ken, do you have some specifics - company names, contact points?
> <unrelated>
> I'm attempting to (re)move libglapi to GLVND and having some other
> people to weight in will be appreciated.
> </unrelated>
> 
>>
>>
>> So how does this interact with libglvnd? I would assume those old drivers
>> are not going to work with libglvnd. Will they need to be packaged
>> separately with there own libGL build in future anyway? Or will they still
>> work?
>>
> They still work, since the libglapi ABI is unchanged. I haven't
> checked the old DRI1 modules but ancient DRI2 ones with GLVND are
> fine.

I see. I've never looked to far into how libglvnd works but I was hoping 
that it meant we could have multiple Mesa distributions e.g dri1 
drivers, old to semi modern drivers (all classic besides i965, up to 
r300 gallium), and current Mesa. Where each would have their own version 
of libglapi and all the drivers could co-exist on the system, allowing 
us to clean things up and not worry about backwards compat.

Anyway it seems that's not how it works at all which makes libglvnd a 
little less exciting in my mind :(


> On the patch itself I need to double-check, but I think it would be
> fine. Please don't quote me :-)
> 
>> Personally I'm hoping other distros follow Fedoras lead and start using
>> libglvnd so we can split out even more old drivers into a separate project
>> and do some much needed tidy-up.
>>
> And i wish people are more careful as they write patches - ~1/2 of the
> patches in Fedora are broken ;-)
> 
> Back on topic, a most of the tidy ups depend on:
>   - deprecating ancient DRI loader/drivers support (note DRI1 is
> unchanged), as just mentioned in another thread.
>   - lifting and splitting out the shared glapi from the almost
> exclusively Win32 specific static one.
> 
> -Emil
>