It appears that controlling the calling convention is exactly what Mulle-objc is doing. It's layering a new convention on top of C calling conventions, where ob

It appears that controlling the calling convention is exactly what Mulle-objc is doing. It's layering a new convention on top of C calling conventions, where objc_msgSend() is given a pointer to a struct containing the arguments. This way the compiler can synthesize the struct for you, and objc_msgSend() itself can be written in vanilla C.