The warning silenced was:
libavfilter/avfiltergraph.c: In function ‘avfilter_graph_config’:
libavfilter/avfiltergraph.c:500:13: warning: ‘best_idx’ may be used uninitialized in this function [-Wuninitialized]

The warning silenced was:
libavfilter/af_join.c: In function ‘join_request_frame’:
libavfilter/af_join.c:451:9: warning: ‘nb_samples’ may be used uninitialized in this function [-Wuninitialized]

It is a plain int now.

Move private fields to the private section, remove holes.

Place related fields together, remove holes.

Place related fields together, remove holes, move private fields to the
end and mark them as private.

Place related fields together, remove holes.

Place related fields together, remove holes.

It is not used in any filters currently and is inherently evil. If
passing binary data to filters is required in the future, it should be
done with some AVOptions-based system.

Inspired by MPlayer's af_channels filter and SoX's remix effect.

It joins multiple input streams into one multi-channel output.

This makes synchronization simpler for filters with multiple inputs.

This breaks libavfilter ABI.

It currently does the following:
1) get a zeroed audio buffer
2) copy some properties (but not the data) of the input buffer to it
3) pass this buffer to the output filter
This looks useless and is indeed not used by any filters, therefore
delete it.

Make ff_null_filter_samples() (just pass the buffer to the next filter)
the new default.

It's redundant, since the input buffer is passed as a parameter to the
filter_samples() callback, and can lead to stale pointers remaining on
the link.

It will be used for audio too.

Fixes a possible invalid write, found by Nicolas George.

This is more consistent with naming in the rest of Libav.

It will allow adding new fields to it without ABI breaks.

This will allow making AVFilterPad opaque for the calling apps, since
those are the only two fields that can be useful to the users.

They are only useful inside filters and we don't allow user filters for
now.

Fix build after b74a1da4.

They are only useful inside filters and we don't allow user filters for
now.

They are only useful inside filters and we don't allow user filters for
now.