libavcodec/fmvc.c:241: error: Uninitialized Value
  The value read from opcode was never initialized.

libavcodec/fmvc.c:241:9: 
239.             continue;
240.         }
241.         len = opcode & 7;
             ^
242.         if (!len) {
243.             if (!bytestream2_peek_byte(gb)) {
