Comment by jcranmer

Sorry, this explanation is plain wrong.

You can cast between pointer types freely so long as they can be representable in one another (some casts are undefined because the address would be unaligned in the target pointer type, and there's actually no guarantee that pointers to objects and pointers to functions have the same representation).

Strict aliasing rules don't kick in at pointer type casting, but rather kick in at lvalue access--when you dereference a pointer, in other words--and you've also given the list of strict aliasing rules completely incorrectly.