libavformat/mpegtsenc.c:591: error: Uninitialized Value
  The value read from buf[_] was never initialized.

libavformat/mpegtsenc.c:591:17: 
589.             if (buf[3] & 0x20) {
590.                 /* stuffing already present: increase its size */
591.                 afc_len = buf[4] + 1;
                     ^
592.                 memmove(buf + 4 + afc_len + stuffing_len,
593.                         buf + 4 + afc_len,
