[FFmpeg-devel] [PATCH] configure: improve logic and checks for nvenc

[Carl Eugen Hoyos]

2016-08-31 15:26 GMT+02:00 Timo Rothenpieler <timo at rothenpieler.org>:
>> 2016-08-31 15:03 GMT+02:00 Timo Rothenpieler <timo at rothenpieler.org>:
>>> Forgot this, the idea with my approach is to handle the case where
>>> --enable-nvenc is requested, but the compile-check fails.
>>
>>> Just silently disabling it then seems wrong.

It's what FFmpeg does for more than a decade.

>> But this is what we do for all auto-detected features except xcb. If changing
>> this comes at the price of far more complicated checks, I suggest we keep
>> the current logic.
>
> Hm, just silently disabling stuff that's explicitly requested to be
> enabled via enable seems broken.
> It might also result in builds which show a feature to be enabled in the
> configure line they show, while it's actually disabled because of a
> failed check/missing library.

This is exactly why I ask Zeranoe (and Alexis) since several years to
remove "--enable-zlib --enable-bzlib" from their configure lines, so far
my success was limiited;-(

I'd like to repeat that if this new feature comes at the price of
significantly more complicated checks in the configure script,
we should probably not change the established logic.
(Correct me if I misremember: It was tried already but resulted in
completely broken configure?)

Carl Eugen