libavcodec/qdm2.c:975: error: Uninitialized Value
  The value read from sign_bits[_] was never initialized.

libavcodec/qdm2.c:975:33: 
973.                             q->tone_level[0][sb][(j + k) / 2] * samples[k];
974.                         if (q->nb_channels == 2) {
975.                             if (sign_bits[(j + k) / 8])
                                     ^
976.                                 q->sb_samples[1][j + k][sb] =
977.                                     q->tone_level[1][sb][(j + k) / 2] * -samples[k];
