diff --git a/gcompat.h b/gcompat.h
index 9f6f1f6..66fb781 100644
--- a/gcompat.h
+++ b/gcompat.h
@@ -24,4 +24,9 @@
 }
 #endif
 
+#if GTK_MAJOR_VERSION < 3
+guint gtk_widget_get_allocated_width(GtkWidget *w);
+guint gtk_widget_get_allocated_height(GtkWidget *w);
+#endif
+
 #endif