Most of the invalid usages due to the conversion from uintptr to
unsafe.Pointer. In general, unsafe.Pointer(p) where p of type uintptr is
considered unsafe.
To fix that, use &p instead of p, then introduce another dereference.
Example, the invalid usage:
*(*int)(unsafe.Pointer(p)) = int(v)
wil become:
**(**int)(unsafe.Pointer(&p)) = int(v)
Closes#53