libavcodec/alac.c:456: error: Uninitialized Value
  The value read from prediction_type[_] was never initialized.

libavcodec/alac.c:456:17: 
454. 
455.             /* adaptive FIR filter */
456.             if (prediction_type[ch] == 15) {
                     ^
457.                 /* Prediction type 15 runs the adaptive FIR twice.
458.                  * The first pass uses the special-case coef_num = 31, while
