// currently defined level 1 element
mkv->main_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 10);
mkv->cluster_seekhead = mkv_start_seekhead(pb, mkv->segment_offset, 0);
+ if (mkv->main_seekhead == NULL || mkv->cluster_seekhead == NULL)
+ return AVERROR(ENOMEM);
if (mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_INFO, url_ftell(pb)) < 0)
return -1;