(let ((type (parse-alien-type spec env)))
(if (or (alien-integer-type-p type)
(alien-float-type-p type)
- (alien-pointer-type-p type))
+ (alien-pointer-type-p type)
+ (alien-system-area-pointer-type-p type))
(ceiling (alien-type-word-aligned-bits type) sb!vm:n-byte-bits)
(error "Unsupported callback argument type: ~A" type))))