#![allow(dead_code, deprecated, unused_variables, unused_mut)]
#![feature(ptr_mask)]
fn main() {
    let v = 17_u32;
    let ptr: *const u32 = &v;
    let tag_mask = 0b11;
    let ptr_mask = !tag_mask;
    let tagged_ptr = ptr.map_addr(|a| a | 0b10);
    let tag = tagged_ptr.addr() & tag_mask;
    assert_eq!(tag, 0b10);
    let masked_ptr = tagged_ptr.mask(ptr_mask);
    assert_eq!(unsafe { * masked_ptr }, 17);
}