libavcodec/mjpegdec.c:865: error: Uninitialized Value
  The value read from linesize[_] was never initialized.

libavcodec/mjpegdec.c:865:29: 
863.                     if (!s->progressive) {
864.                         if (copy_mb)
865.                             copy_block8(ptr, reference_data[c] + block_offset,
                                 ^
866.                                         linesize[c], linesize[c], 8);
867.                         else {
