anchor.diff:      (error err)))
   
   (defun check-cells-quota (vm)
  +  (declare (optimize speed))
     (labels ((quota-exceeded ()
                (and (vm-cells-quota vm)
  -                  (> (vm-used-cells vm) (vm-cells-quota vm)))))
  +                  (> (the fixnum (vm-used-cells vm))
  +                     (the fixnum (vm-cells-quota vm))))))
       (when (quota-exceeded)
         (vm-count-used-cells vm)
         (when (quota-exceeded)
  
positive.code:          (is-required-primitive (callable-prim0 callable))
           (primitive-arity (second primitive-record))
           (current-program-counter (vm-program-counter vm)))
      (when (and primitive-arity (/= primitive-arity num-args))
        (arity-error vm primitive-arity num-args))
      (if is-required-primitive
  
negative.code:         (vm-current-environment vm) (return-address-environment retaddr)))
  
  (defun handle-args (vm args)
    (declare (optimize speed (safety 0))
             (type fixnum args))
    (when (< 0 args)
      (let* ((stack (vm-stack vm))
             (return-address (if (return-address-p (first stack)) (pop stack)))
  