diff --git a/src/test-network.c b/src/test-network.c
index 0cac1a4..73062f4 100644
--- a/src/test-network.c
+++ b/src/test-network.c
@@ -351,7 +351,7 @@ int main(int argc, char** argv) {
 
 	// Lookup an address in the subnet
 	err = loc_database_lookup_from_string(db, "2001:db8::", &network1);
-	if (err) {
+	if (err || !network1) {
 		fprintf(stderr, "Could not look up 2001:db8::\n");
 		exit(EXIT_FAILURE);
 	}