libavcodec/fmvc.c:364: error: Uninitialized Value
  The value read from opcode was never initialized.

libavcodec/fmvc.c:364:9: 
362.             } while (len && bytestream2_get_bytes_left(&gbc) > 0);
363.         }
364.         len = opcode & 0x1F;
             ^
365.         if (!len) {
366.             if (!bytestream2_peek_byte(gb)) {
