--- a/atk-adaptor/bridge.c
+++ b/atk-adaptor/bridge.c
@@ -646,6 +646,7 @@
   socket_class->embed = socket_embed_hook;
 }
 
+#ifndef _WIN32
 static guint
 get_ancestral_uid (guint pid)
 {
@@ -678,6 +679,7 @@
     return 0;
   return get_ancestral_uid (ppid);
 }
+#endif
 
 static dbus_bool_t
 user_check (DBusConnection *bus, unsigned long uid, void *data)