In C, I need to know the size of a struct, which has function pointers in it. Can I be guaranteed that on all platforms and architectures:

* the size of a void\* is the same size as a function pointer?
* the size of the function pointer does not differ due to its return type?
* the size of the function pointer does not differ due to its parameter types?

I assume the answer is yes to all of these, but I want to be sure. For context, I'm calling `sizeof(struct mystruct)` and nothing more.