;; stack guard pages.
(values-subtypep (lvar-derived-type words)
(load-time-value
- (specifier-type `(integer 0 ,(- (/ sb!vm::*backend-page-size*
+ (specifier-type `(integer 0 ,(- (/ sb!vm::*backend-page-bytes*
sb!vm:n-word-bytes)
sb!vm:vector-data-offset)))))))