+ (binding-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ (binding-stack-pointer :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ (control-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ (control-stack-end :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ (alien-stack-start :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ (alien-stack-pointer :c-type "lispobj *" :length #!+alpha 2 #!-alpha 1)
+ #!+gencgc (alloc-region :c-type "struct alloc_region" :length 5)