libavcodec/dvdec.c:296: error: Uninitialized Value
  The value read from is_field_mode[_] was never initialized.

libavcodec/dvdec.c:296:9: 
294.         y_ptr    = s->frame->data[0] +
295.                    ((mb_y * s->frame->linesize[0] + mb_x) << log2_blocksize);
296.         linesize = s->frame->linesize[0] << is_field_mode[mb_index];
             ^
297.         mb[0].idct_put(y_ptr, linesize, block + 0 * 64);
298.         if (s->sys->video_stype == 4) { /* SD 422 */
