(import foreign)

(foreign-declare "void func(int* x, int* y) { *x = 21; *y = 42; }")

(define (func)
  (let-location ((x1 int)
                 (x2 int))
    ((foreign-lambda void func (c-pointer int) (c-pointer int))
     (location x1)
     (location x2))
    (values x1 x2)))