--- src/xsettings.c.orig
+++ src/xsettings.c
@@ -1054,12 +1054,14 @@
 
 #if GLIB_CHECK_VERSION (2, 32, 0)
   {
-    GSettingsSchema *sc = g_settings_schema_source_lookup
-      (g_settings_schema_source_get_default (),
-       GSETTINGS_SCHEMA,
-       true);
-    schema_found = sc != NULL;
-    if (sc) g_settings_schema_unref (sc);
+    GSettingsSchemaSource *source = g_settings_schema_source_get_default ();
+    if (source != NULL)
+      {
+	GSettingsSchema *sc = g_settings_schema_source_lookup
+	  (source, GSETTINGS_SCHEMA, true);
+	schema_found = sc != NULL;
+	if (sc) g_settings_schema_unref (sc);
+      }
   }
 #else
   {
--- src/pgtkfns.c.orig
+++ src/pgtkfns.c
@@ -1885,6 +1885,8 @@
 
   /* check existence of setting_key */
   GSettingsSchemaSource *ssrc = g_settings_schema_source_get_default ();
+  if (ssrc == NULL)
+    return NULL;	/* no GSettings schemas installed. */
   GSettingsSchema *scm = g_settings_schema_source_lookup (ssrc, SCHEMA_ID, TRUE);
   if (!scm)
     return NULL;	/* *.schema.xml is not installed. */