diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index 6a99dac8e..3be4eba3d 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -1220,6 +1220,8 @@ g_date_time_new_ordinal (GTimeZone *tz, gint year, gint ordinal_day, gint hour,
     return NULL;
 
   dt = g_date_time_new (tz, year, 1, 1, hour, minute, seconds);
+  if (dt == NULL)
+    return NULL;
   dt->days += ordinal_day - 1;
 
   return dt;
@@ -1239,6 +1241,8 @@ g_date_time_new_week (GTimeZone *tz, gint year, gint week, gint week_day, gint h
     return NULL;
 
   dt = g_date_time_new (tz, year, 1, 4, 0, 0, 0);
+  if (dt == NULL)
+    return NULL;
   g_date_time_get_week_number (dt, NULL, &jan4_week_day, NULL);
   g_date_time_unref (dt);
 
diff --git a/glib/tests/gdatetime.c b/glib/tests/gdatetime.c
index 23d83b7d0..4ecccb347 100644
--- a/glib/tests/gdatetime.c
+++ b/glib/tests/gdatetime.c
@@ -866,6 +866,9 @@ test_GDateTime_new_from_iso8601_2 (void)
     { TRUE, "+1980-02-22T12:36:00+02:00", 1980, 2, 22, 12, 36, 0, 0, 2 * G_TIME_SPAN_HOUR },
     { TRUE, "1990-11-01T10:21:17     ", 1990, 11, 1, 10, 21, 17, 0, 0 },
     */
+    { FALSE, "1719W462 407777-07", 0, 0, 0, 0, 0, 0, 0, 0 },
+    { FALSE, "4011090 260528Z", 0, 0, 0, 0, 0, 0, 0, 0 },
+    { FALSE, "0000W011 228214-22", 0, 0, 0, 0, 0, 0, 0, 0 },
   };
   GTimeZone *tz = NULL;
   GDateTime *dt = NULL;