fix _short' and other non-_int' integer types, and add `_intptr' test

collects/ffi/unsafe.rkt

@@ -47,7 +47,7 @@
 
 ;; utility for the next few definitions
 (define (sizeof->3ints c-type)
-  (case (compiler-sizeof 'int)
+  (case (compiler-sizeof c-type)
     [(2) (values _int16 _uint16 _int16)]
     [(4) (values _int32 _uint32 _int32)]
     [(8) (values _int64 _uint64 _int64)]

collects/tests/racket/foreign-test.rktl

@@ -234,6 +234,11 @@
   (test 1 ptr-ref v _int16 0)
   (test 3 ptr-ref v _int16 3))
 
+;; Test intptr:
+(let ([v (malloc _pointer)])
+  (ptr-set! v _pointer (ptr-add #f 107))
+  (test 107 ptr-ref v _intptr))
+
 (delete-test-files)
 
 (report-errs)