libavcodec/fmvc.c:351: error: Uninitialized Value
  The value read from opcode was never initialized.

libavcodec/fmvc.c:351:17: 
349.             }
350.             high = 0;
351.             if (opcode < 0x40)
                     ^
352.                 break;
353.             bytestream2_init(&gbc, pb->buffer_start, pb->buffer_end - pb->buffer_start);
