<ERR> filters, line 1: Missing AS_PATH attribute

Hi, In our BIRD 2.14 we’re running roa_check like this: if (net.type = NET_IP4) then { case roa_check(r4, net, bgp_path.last) { However, the BIRD logs show the following error: <ERR> filters, line 1: Missing AS_PATH attribute would it be advisable to add a check to determine whether the route is a BGP route before proceeding?