libavcodec/gif.c:112: error: Uninitialized Value
  The value read from len was never initialized.

libavcodec/gif.c:112:5: 
110.         ptr += linesize;
111.     }
112.     len += ff_lzw_encode_flush(s->lzw, flush_put_bits);
         ^
113. 
114.     ptr = s->buf;
