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use std::ptr;
const IS_NULL: () = {
assert!(ptr::null::<u8>().is_null());
};
const IS_NOT_NULL: () = {
assert!(!ptr::null::<u8>().wrapping_add(1).is_null());
};
const MAYBE_NULL: () = {
let x = 15;
let ptr = &x as *const i32;
// This one is still unambiguous...
assert!(!ptr.is_null());
// and in fact, any offset not visible by 4 (the alignment) cannot be null,
// even if it goes out-of-bounds...
assert!(!ptr.wrapping_byte_add(13).is_null());
assert!(!ptr.wrapping_byte_add(18).is_null());
assert!(!ptr.wrapping_byte_sub(1).is_null());
// ... but once we shift outside the allocation, with an offset divisible by 4,
// we might become null.
assert!(!ptr.wrapping_sub(512).is_null()); //~inside `MAYBE_NULL`
};
fn main() {}
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