diff --git a/tests/unittests/tests-ipv6_netif/tests-ipv6_netif.c b/tests/unittests/tests-ipv6_netif/tests-ipv6_netif.c
index fbec6624db..81190f2d14 100644
--- a/tests/unittests/tests-ipv6_netif/tests-ipv6_netif.c
+++ b/tests/unittests/tests-ipv6_netif/tests-ipv6_netif.c
@@ -87,7 +87,7 @@ static void test_netif_add__success_with_ipv6(void)
 
     ng_netif_add(DEFAULT_TEST_NETIF);
 
-    TEST_ASSERT_NOT_NULL((pid_num = ng_netif_get(pids)));
+    TEST_ASSERT_EQUAL_INT(1, (pid_num = ng_netif_get(pids)));
     TEST_ASSERT_EQUAL_INT(1, pid_num);
     TEST_ASSERT_EQUAL_INT(DEFAULT_TEST_NETIF, pids[0]);
     TEST_ASSERT_NOT_NULL((entry = ng_ipv6_netif_get(DEFAULT_TEST_NETIF)));