[FFmpeg-devel] [PATCH] configure: request explicitly enabled components

[Carl Eugen Hoyos]

2019-02-05 1:13 GMT+01:00, Hendrik Leppkes <h.leppkes at gmail.com>:
> On Tue, Feb 5, 2019 at 1:01 AM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>>
>> 2019-02-05 0:53 GMT+01:00, Marton Balint <cus at passwd.hu>:
>> >
>> >
>> > On Tue, 5 Feb 2019, Carl Eugen Hoyos wrote:
>> >
>> >> 2019-02-03 16:24 GMT+01:00, Marton Balint <cus at passwd.hu>:
>> >>>
>> >>>
>> >>> On Sun, 3 Feb 2019, Carl Eugen Hoyos wrote:
>> >>>
>> >>>> 2019-01-28 2:00 GMT+01:00, Marton Balint <cus at passwd.hu>:
>> >>>>> If we enable a component but a dependant library is disabled, then
>> >>>>> the
>> >>>>> enabled
>> >>>>> component get silently disabled. Requesting all explicitly enabled
>> >>>>> components
>> >>>>> allows configure to fail and show the missing dependencies instead
>> >>>>> of
>> >>>>> ignoring
>> >>>>> our request.
>> >>>>>
>> >>>>> For example if libdav1d is not availble ./configure
>> >>>>> --enable-decoder=libdav1d
>> >>>>> succeeds but the libdav1d decoder will not be enabled. After the
>> >>>>> patch
>> >>>>> the
>> >>>>> configure line will fail with the following message:
>> >>>>> ERROR: libdav1d_decoder requested, but not all dependencies are
>> >>>>> satisfied:
>> >>>>> libdav1d
>> >>>>>
>> >>>>> Signed-off-by: Marton Balint <cus at passwd.hu>
>> >>>>> ---
>> >>>>>  configure | 1 +
>> >>>>>  1 file changed, 1 insertion(+)
>> >>>>>
>> >>>>> diff --git a/configure b/configure
>> >>>>> index e1412352fa..1f6c6a7311 100755
>> >>>>> --- a/configure
>> >>>>> +++ b/configure
>> >>>>> @@ -3881,6 +3881,7 @@ for opt do
>> >>>>>              list=$(filter "$name" $list)
>> >>>>>              [ "$list" = "" ] && warn "Option $opt did not match
>> >>>>> anything"
>> >>>>>              $action $list
>> >>>>
>> >>>>> +            test $action = enable && request $list
>> >>>>
>> >>>> I strongly suspect that this will break regression tests.
>> >>>
>> >>> You mean fate with different configure options?
>> >>
>> >> No, I believe this would break regression tests with
>> >> --disable-everything (and an enable for a feature that
>> >> was added in the meantime and is needed to reproduce
>> >> the issue).
>> >
>> > Could you give a more concrete example? I am not sure I
>> > understand what you mean.
>>
>> $ ./configure --disable-everything --enable-bsf=prores_metadata
>> currently does not fail for current FFmpeg and 936d18fb, this
>> would change for future new features with your patch.
>>
>
> What sort of testing would involve trying to enable a certain
> component, and then *succeeding* when the component does not exist?

Several regression tests have needed that in the past, I find it
strange that you seem to imply this will not happen in the
future.
Or is that not what you were saying?

Carl Eugen