[FFmpeg-devel] [PATCH] configure: libvmaf requires pthreads

[Timo Rothenpieler]

On 13.11.2020 02:23, lance.lmwang at gmail.com wrote:
> On Fri, Nov 13, 2020 at 02:14:05AM +0100, Timo Rothenpieler wrote:
>> On 13.11.2020 02:05, lance.lmwang at gmail.com wrote:
>>> On Thu, Nov 12, 2020 at 05:56:57PM +0100, Timo Rothenpieler wrote:
>>>> Technically, libvmaf itself does not, but our filter does, and there is
>>>> no other sensible way to prevent a build with --enable-libvmaf from
>>>> succeeding while not actually enabling the filter.
>>>
>>> If it's private filter, I think you it's better to add the pthread depends for your filter
>>> only, search for libvmaf_filter_deps
>>
>> The filter already depends on pthreads correctly.
>> This is about the issue where you can produce a build that is configured
>> with --enable-libvmaf, but which does not have the libvmaf filter.
>>
>> Happens for example on Win32, where w32threads are used by default.
> 
> so it doesn't work with  --enable-pthreads also?

Of course it does, but there is no indication for that to the user 
whatsoever.
And given that there is only that one consumer of --enable-libvmaf, the 
libvmaf filter, which also depends on pthreads, adding an error like 
this seems appropriate to inform users about the pthread requirement.