libavcodec/mjpegdec.c:857: error: Uninitialized Value
  The value read from linesize[_] was never initialized.

libavcodec/mjpegdec.c:857:21: 
855.                 y = 0;
856.                 for (j = 0; j < n; j++) {
857.                     block_offset = ((linesize[c] * (v * mb_y + y) * 8) +
                         ^
858.                                     (h * mb_x + x) * 8);
859. 
