diff --git a/gtk/gtkwidgetprivate.h b/gtk/gtkwidgetprivate.h
index c5768a29d3..009e2a548f 100644
--- a/gtk/gtkwidgetprivate.h
+++ b/gtk/gtkwidgetprivate.h
@@ -236,8 +236,6 @@ void              _gtk_widget_synthesize_crossing          (GtkWidget       *fro
                                                             GdkDevice       *device,
                                                             GdkCrossingMode  mode);
 
-static inline gpointer _gtk_widget_peek_request_cache           (GtkWidget *widget);
-
 void              _gtk_widget_buildable_finish_accelerator (GtkWidget *widget,
                                                             GtkWidget *toplevel,
                                                             gpointer   user_data);