Thanks for the comment!

On OS X if OBJC_OLD_DISPATCH_PROTOTYPES is not defined, you will get this declaration with zero arguments: void objc_msgSend(void /* id self, SEL op, ... */ ), which is possible to call from C without cast by using implicit function declaration, but this call will fail if compiled as Objective-C code with error "too many arguments to function call", I've decided to write in a style that compiles as C and Objective-C code.

PS. Would be nice to be able to use functions from clang Objective-C runtime [1], but for some reason they are not exposed in the public headers.

- [1] http://clang.llvm.org/docs/AutomaticReferenceCounting.html#r...