diff --git a/lwlib/lwlib-Xaw.h b/lwlib/lwlib-Xaw.h
index 363334b575e..644676f320d 100644
--- a/lwlib/lwlib-Xaw.h
+++ b/lwlib/lwlib-Xaw.h
@@ -15,15 +15,13 @@ void
 xaw_update_one_widget (widget_instance *, Widget, widget_value *, Boolean);
 
 void
-xaw_update_one_value (widget_instance *, Widget, widget_value *)
-  ATTRIBUTE_CONST;
+xaw_update_one_value (widget_instance *, Widget, widget_value *);
 
 void
 xaw_destroy_instance (widget_instance *);
 
 void
-xaw_popup_menu (Widget, XEvent *)
-  ATTRIBUTE_CONST;
+xaw_popup_menu (Widget, XEvent *);
 
 void
 xaw_pop_instance (widget_instance *, Boolean);
diff --git a/lwlib/lwlib-Xlw.h b/lwlib/lwlib-Xlw.h
index 2d38eb7be66..b0790dc3a59 100644
--- a/lwlib/lwlib-Xlw.h
+++ b/lwlib/lwlib-Xlw.h
@@ -15,15 +15,13 @@ xlw_update_one_widget (widget_instance* instance, Widget widget,
 
 void
 xlw_update_one_value (widget_instance* instance, Widget widget,
-		      widget_value* val)
-  ATTRIBUTE_CONST;
+		      widget_value* val);
 
 void
 xlw_destroy_instance (widget_instance* instance);
 
 void
-xlw_pop_instance (widget_instance* instance, Boolean up)
-  ATTRIBUTE_CONST;
+xlw_pop_instance (widget_instance* instance, Boolean up);
 
 void
 xlw_popup_menu (Widget widget, XEvent * event);
diff --git a/lwlib/lwlib.h b/lwlib/lwlib.h
index 66730fd8d77..41d3e0139d2 100644
--- a/lwlib/lwlib.h
+++ b/lwlib/lwlib.h
@@ -111,15 +111,9 @@ void lw_refigure_widget (Widget w, Boolean doit);
 Boolean lw_window_is_in_menubar (Window win, Widget menubar_widget);
 
 /* Manage resizing: TRUE permits resizing widget w; FALSE disallows it. */
-#ifndef USE_MOTIF
-ATTRIBUTE_CONST
-#endif
 void lw_allow_resizing (Widget w, Boolean flag);
 
 /* Set up the main window. */
-#ifndef USE_MOTIF
-ATTRIBUTE_CONST
-#endif
 void lw_set_main_areas (Widget parent,
                         Widget menubar,
                         Widget work_area);
diff --git a/src/emacs-module.c b/src/emacs-module.c
index 385c3089a90..956706cf9f5 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -41,6 +41,11 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 # pragma GCC diagnostic ignored "-Wclobbered"
 #endif
 
+/* This module is lackadaisical about function casts.  */
+#if GNUC_PREREQ (8, 0, 0)
+# pragma GCC diagnostic ignored "-Wcast-function-type"
+#endif
+
 /* We use different strategies for allocating the user-visible objects
    (struct emacs_runtime, emacs_env, emacs_value), depending on
    whether the user supplied the -module-assertions flag.  If