libavcodec/vc1_parser.c:196: error: Uninitialized Value
  The value read from b was never initialized.

libavcodec/vc1_parser.c:196:13: 
194.             vc1_extract_header(s, avctx, unesc_buffer, unesc_index);
195. 
196.             vpc->prev_start_code = b;
                 ^
197.             unesc_index = 0;
198. 
