- "The function bound to this variable is invoked after GC'ing with
-the value of *GC-NOTIFY-STREAM*, the amount of dynamic usage (in
-bytes) now free, the number of bytes freed by the GC, and the new GC
-trigger threshold. The function should notify the user that the system
-has finished GC'ing.")
+ "The function bound to this variable is invoked after GC'ing with the
+value of *GC-NOTIFY-STREAM*, the amount of dynamic usage (in bytes) now
+free, the number of bytes freed by the GC, and the new GC trigger
+threshold; or if *GC-NOTIFY-STREAM* is NIL, it's not invoked. The
+function should notify the user that the system has finished GC'ing.")