This is not even worth discussing. A program containing this is ill-formed; it won't compile. http://ideone.com/6OOtFe
Even if it was not as ludicrous, ie. function was actually a function, but with a different type, it would result in undefined behaviour.
The effect of calling a function through a pointer to a function type that is not the same as the type used in the definition of the function is undefined. - IS