BOOL is not a floating point value... so using objc_msgSend_fpret()
to call a method that returns BOOL would be especially heinous.
Ack, at 2/12/06, Damien Bobillot said:
Greg Parker wrote :
Don't do this. In the BOOL case it works, I think. In other cases
it fails (for example, if you cast to double instead of BOOL).
Using an appropriately-typed function pointer always works.
According to the objc-runtime.h header, one must use
objc_msgSend_fpret on i386 for methods returning a double value :
/* Floating-point-returning Messaging Primitives (prototypes)
*
* On some platforms, the ABI for functions returning a floating-point
* value is incompatible with that for functions returning an integral type.
* objc_msgSend_fpret must be used for these.
*
* ppc: objc_msgSend_fpret not used
* ppc64: objc_msgSend_fpret not used
* i386: objc_msgSend_fpret REQUIRED
*
* For `float` or `long double` return types, cast the function
* to an appropriate function pointer type first.
*/
#ifdef __i386__
OBJC_EXPORT double objc_msgSend_fpret(id self, SEL op, ...);
#endif
--
Sincerely,
Rosyna Keller
Technical Support/Holy Knight/Always needs a hug
Unsanity: Unsane Tools for Insanely Great People
It's either this, or imagining Phil Schiller in a thong.
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