libavcodec/wmadec.c:641: error: Uninitialized Value
  The value read from nb_coefs[_] was never initialized.

libavcodec/wmadec.c:641:17: 
639.                 for(i = 0;i < s->coefs_start; i++)
640.                     *coefs++ = 0.0;
641.                 n = nb_coefs[ch];
                     ^
642.                 for(i = 0;i < n; i++) {
643.                     *coefs++ = coefs1[i] * exponents[i<<bsize>>esize] * mult;
