Index: uspace/drv/test/test1/test1.c
===================================================================
--- uspace/drv/test/test1/test1.c	(revision 09ab0a9afc9379f1604c0fd75cac2d9287ba022c)
+++ uspace/drv/test/test1/test1.c	(revision 4f87a85ae8e0c4b41a1e0120338b46dd9654fc9c)
@@ -176,5 +176,12 @@
 	}
 
-	ddf_fun_add_to_category(fun_a, "virtual");
+	rc = ddf_fun_add_to_category(fun_a, "virtual");
+	if (rc != EOK) {
+		ddf_msg(LVL_ERROR, "Failed adding function 'a' to category "
+		    "'virtual'.");
+		ddf_fun_unbind(fun_a);
+		ddf_fun_destroy(fun_a);
+		goto error;
+	}
 
 	if (str_cmp(dev_name, "test1") == 0) {