diff --git a/lib/dns/rpz.c b/lib/dns/rpz.c
index 5ed2d2c00d..65c94baf83 100644
--- a/lib/dns/rpz.c
+++ b/lib/dns/rpz.c
@@ -191,6 +191,7 @@ dns_rpz_policy2str(dns_rpz_policy_t policy) {
 		break;
 	default:
 		str = "";
+		POST(str);
 		INSIST(0);
 	}
 	return (str);