diff --git a/bleh_darwin.m b/bleh_darwin.m
index 5a2cbcf..2ef6c21 100644
--- a/bleh_darwin.m
+++ b/bleh_darwin.m
@@ -6,6 +6,7 @@ I wanted to avoid invoking Objective-C directly, preferring to do everything dir
 The main culprits are:
 - data types listed as being defined in nonexistent headers
 - 32-bit/64-bit type differences that are more than just a different typedef
+- wrong documentation
 
 Go wrapper functions (bleh_darwin.go) call these directly and take care of stdint.h -> Go type conversions.
 */
@@ -29,12 +30,18 @@ These are the objc_msgSend() wrappers around NSRect. The problem is that while o
 I use int64_t for maximum safety, as my coordinates are stored as Go ints and Go int -> C int (which is what is documented as happening) isn't reliable.
 */
 
+/*
+This is not documented in the docs, but is in various places on apple.com. In fact, the docs are actually WRONG: they imply you pass a pointer to the structure as the first argument to objc_msgSend_stret! And there might be some cases where we can't use stret because the struct is small enough... we'll see.
+*/
+static NSRect (*objc_msgSend_stret_rect)(id, SEL, ...) =
+	(NSRect (*)(id, SEL, ...)) objc_msgSend_stret;
+
 struct xrect objc_msgSend_stret_rect_noargs(id obj, SEL sel)
 {
 	NSRect s;
 	struct xrect t;
 
-	objc_msgSend_stret(&s, obj, sel);
+	s = objc_msgSend_stret_rect(obj, sel);
 	t.x = (int64_t) s.origin.x;
 	t.y = (int64_t) s.origin.y;
 	t.width = (int64_t) s.size.width;
@@ -42,7 +49,6 @@ struct xrect objc_msgSend_stret_rect_noargs(id obj, SEL sel)
 	return t;
 }
 
-
 #define OurRect() (NSMakeRect((CGFloat) x, (CGFloat) y, (CGFloat) w, (CGFloat) h))
 
 id _objc_msgSend_rect(id obj, SEL sel, int64_t x, int64_t y, int64_t w, int64_t h)
@@ -64,12 +70,15 @@ id _objc_msgSend_rect_uint_uint_bool(id obj, SEL sel, int64_t x, int64_t y, int6
 Same as NSRect above, but for NSSize now.
 */
 
+static NSSize (*objc_msgSend_stret_size)(id, SEL, ...) =
+	(NSSize (*)(id, SEL, ...)) objc_msgSend_stret;
+
 struct xsize objc_msgSend_stret_size_noargs(id obj, SEL sel)
 {
 	NSSize s;
 	struct xsize t;
 
-	objc_msgSend_stret(&s, obj, sel);
+	s = objc_msgSend_stret_size(obj, sel);
 	t.width = (int64_t) s.width;
 	t.height = (int64_t) s.height;
 	return t;