libavcodec/proresenc.c:537: error: Uninitialized Value
  The value read from num_cblocks[_] was never initialized.

libavcodec/proresenc.c:537:21: 
535.         error = 0;
536.         for (i = 0; i < ctx->num_planes; i++) {
537.             bits += estimate_slice_plane(ctx, &error, i,
                         ^
538.                                          src, pic->linesize[i],
539.                                          mbs_per_slice,
