diff --git a/gtk/gtk.symbols b/gtk/gtk.symbols
index 439ebc8e4a..a276bf8878 100644
--- a/gtk/gtk.symbols
+++ b/gtk/gtk.symbols
@@ -5058,6 +5058,7 @@ gtk_widget_reset_rc_styles
 gtk_widget_reset_shapes
 gtk_widget_send_expose
 gtk_widget_set_accel_path
+gtk_widget_set_allocation
 gtk_widget_set_app_paintable
 gtk_widget_set_child_visible
 gtk_widget_set_colormap
diff --git a/gtk/gtkwidget.h b/gtk/gtkwidget.h
index 3a79f554b0..0838083bed 100644
--- a/gtk/gtkwidget.h
+++ b/gtk/gtkwidget.h
@@ -607,6 +607,8 @@ GdkWindow*            gtk_widget_get_window             (GtkWidget    *widget);
 
 void                  gtk_widget_get_allocation         (GtkWidget     *widget,
                                                          GtkAllocation *allocation);
+void                  gtk_widget_set_allocation         (GtkWidget     *widget,
+                                                         const GtkAllocation *allocation);
 
 gboolean   gtk_widget_child_focus         (GtkWidget           *widget,
                                            GtkDirectionType     direction);