-#define print_disk_util(dus, agg, terse)
-#define show_disk_util(terse, parent)
-#define free_disk_util()
+/* keep this as a function to avoid a warning in handle_du() */
+static inline void print_disk_util(struct disk_util_stat *du,
+ struct disk_util_agg *agg, int terse,
+ struct buf_output *out)
+{
+}
+#define show_disk_util(terse, parent, out)
+#define disk_util_prune_entries()