FSF Emacs has a variable garbage-collection-messages, nil by
default.
This allows a user to decide whether to see that
"Garbage collecting..." messages repeatedly.
2001-09-13 Tetsuo Tsukamoto <czkmt(a)remus.dti.ne.jp>
* alloc.c (garbage_collection_messages): New variable from
FSF Emacs 19.31.
(vars_of_alloc): Set up Lisp variable.
(Fgarbage_collect_1): Variable controls whether to display
messages.
--
Tetsuo Tsukamoto