libavcodec/aacsbr.c:724: error: Uninitialized Value
  The value read from num_rel_lead was never initialized.

libavcodec/aacsbr.c:724:46: 
722. 
723.     if (ch_data->bs_frame_class & 1) { // FIXVAR or VARVAR
724.         for (i = ch_data->bs_num_env[1] - 1; i > num_rel_lead; i--)
                                                  ^
725.             ch_data->t_env[i] = ch_data->t_env[i + 1] -
726.                                 bs_rel_bord[1][ch_data->bs_num_env[1] - 1 - i];
