diff --git a/contrib/gana b/contrib/gana
index df1602616..cb43a2642 160000
--- a/contrib/gana
+++ b/contrib/gana
@@ -1 +1 @@
-Subproject commit df1602616af682c4960d08784b7acba5896dcc81
+Subproject commit cb43a2642dd75f21c45392667e0877c97474915b
diff --git a/src/testing/testing_api_trait_string.c b/src/testing/testing_api_trait_string.c
index 381760113..b102265e8 100644
--- a/src/testing/testing_api_trait_string.c
+++ b/src/testing/testing_api_trait_string.c
@@ -132,10 +132,10 @@ TALER_TESTING_make_trait_url (unsigned int index,
     .ptr = (const void *) url
   };
 
-  GNUNET_assert (0 != strncasecmp (url,
-                                   "payto://",
-                                   strlen ("payto://")));
-
+  GNUNET_assert ( (NULL == url) ||
+                  (0 != strncasecmp (url,
+                                     "payto://",
+                                     strlen ("payto://"))) );
   return ret;
 }