libavcodec/proresenc.c:559: error: Uninitialized Value
  The value read from slice_score[_] was never initialized.

libavcodec/proresenc.c:559:13: 
557. 
558.             bits  = ctx->nodes[prev].bits + slice_bits[q];
559.             error = slice_score[q];
                 ^
560.             if (bits > bits_limit)
561.                 error = SCORE_LIMIT;
