ffi/unsafe: add _size', _ssize', _ptrdiff', _intmax', `_uintmax'

These additions could create backward-compatibility problems, but our
searches suggest that problems will be rare; it's more common for
`_size_t' to be incorrectly aliased to `_int', so having definitions
for these standard types is likely to avoid future problems.

collects/ffi/unsafe.rkt

@@ -93,6 +93,12 @@
 (provide _intptr _uintptr _sintptr)
 (define-values (_intptr _uintptr _sintptr) (sizeof->3ints '(void *)))
 
+(define* _size _uintptr)
+(define* _ssize _intptr)
+(define* _ptrdiff _intptr)
+(define* _intmax _intptr)
+(define* _uintmax _uintptr)
+
 ;; ----------------------------------------------------------------------------
 ;; Getting and setting library objects
 

collects/scribblings/foreign/types.scrbl

@@ -151,6 +151,15 @@ correspond to @racket[_int16]. The @racket[_int] aliases correspond to
 the @racket[_intptr] aliases correspond to either
 @racket[_int32] or @racket[_int64], depending on the platform.}
 
+@defthing*[([_size ctype?]
+            [_ssize ctype?]
+            [_ptrdiff ctype?]
+            [_intmax ctype?]
+            [_uintmax ctype?])]{
+
+More aliases for basic integer types. The @racket[_size] and
+@racket[_uintmax] types are aliases for @racket[_uintptr], and
+the rest are aliases for @racket[_intptr].}
 
 @defthing*[([_fixnum ctype?]
             [_ufixnum ctype?])]{

doc/release-notes/racket/HISTORY.txt

@@ -1,4 +1,5 @@
 Version 5.3.3.3
+ffi/unsafe: added _size, _ssize, _ptrdiff, _intmax, _uintmax
 ffi/vector: added f8vectors
 scribble: 'toc-hidden style on a part no longer hides ToC
  entries for sub-parts when rendering as HTML