libavutil/rc4.c:36: error: Uninitialized Value
  The value read from state[_] was never initialized.

libavutil/rc4.c:36:9: 
34.     for (j = 0, i = 0; i < 256; i++, j++) {
35.         if (j == keylen) j = 0;
36.         y += state[i] + key[j];
            ^
37.         FFSWAP(uint8_t, state[i], state[y]);
38.     }
