diff --git a/libgimp/gimpui.c b/libgimp/gimpui.c
index b7cc74d52f..5e37fde90e 100644
--- a/libgimp/gimpui.c
+++ b/libgimp/gimpui.c
@@ -402,6 +402,10 @@ gimp_osx_focus_window (gpointer user_data)
 }
 #endif
 
+/* Currently broken on Win32 so avoiding a "defined but not used"
+ * warning when building on Windows.
+ */
+#ifndef GDK_WINDOWING_WIN32
 static GdkWindow *
 gimp_ui_get_foreign_window (gpointer window)
 {
@@ -418,6 +422,7 @@ gimp_ui_get_foreign_window (gpointer window)
 
   return NULL;
 }
+#endif
 
 static gboolean
 gimp_window_transient_on_mapped (GtkWidget   *window,