Careful debugging of the memory leak problem. At this stage,

stack frames for interpreted (but not primitive) functions appear not to be being
reclaimed, and the oblist doesn't seem to be being fully reclaimed.

lisp/defun.lisp

@@ -1,9 +1,9 @@
-(set! symbolp (lambda (x) (equal (type x) "SYMB")))
+(set! symbol? (lambda (x) (equal (type x) "SYMB")))
 
 (set! defun!
       (nlambda
        form
-       (cond ((symbolp (car form))
+       (cond ((symbol? (car form))
               (set (car form) (apply 'lambda (cdr form))))
          (t nil))))
 
@@ -17,7 +17,7 @@
 (set! defsp!
       (nlambda
        form
-       (cond (symbolp (car form))
+       (cond (symbol? (car form))
          (set! (car form) (apply nlambda (cdr form))))))
 
 (defsp! cube (x) ((* x x x)))

lisp/fact.lisp

@@ -4,6 +4,6 @@
       (cond ((= n 1) 1)
         (t (* n (fact (- n 1)))))))
 
-; (fact 1000)
+(fact 25)