The C standard says very little about how those types work. In particular, you can cast a pointer to one of them and then cast back to a pointer -- but only if you cast the exact same value back, and the intptr values are not guaranteed to be in any way meaningful.
In particular, casting a pointer to intptr_t, doing arithmetic on it, and casting back is not guaranteed to do anything useful. It almost certainly will, since most systems treat it as roughly the same as casting to char *, but the standard does not guarantee it.
In particular, casting a pointer to intptr_t, doing arithmetic on it, and casting back is not guaranteed to do anything useful. It almost certainly will, since most systems treat it as roughly the same as casting to char *, but the standard does not guarantee it.