libavcodec/wmalosslessdec.c:356: error: Uninitialized Value
  The value read from contains_subframe[_] was never initialized.

libavcodec/wmalosslessdec.c:356:17: 
354.             WmallChannelCtx *chan = &s->channel[c];
355. 
356.             if (contains_subframe[c]) {
                     ^
357.                 if (chan->num_subframes >= MAX_SUBFRAMES) {
358.                     av_log(s->avctx, AV_LOG_ERROR,
