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//@ known-bug: #107975
//@ compile-flags: -Copt-level=2
//@ run-pass
// Derived from https://github.com/rust-lang/rust/issues/107975#issuecomment-1431758601
use std::ptr;
fn main() {
let a: usize = {
let v = 0u8;
ptr::from_ref(&v).expose_provenance()
};
let b: usize = {
let v = 0u8;
ptr::from_ref(&v).expose_provenance()
};
// So, are `a` and `b` equal?
// Let's check their difference.
let i: usize = a - b;
// It's not zero, which means `a` and `b` are not equal.
assert_ne!(i, 0);
// But it looks like zero...
assert_eq!(i.to_string(), "0");
// ...and now it *is* zero?
assert_eq!(i, 0);
// So `a` and `b` are equal after all?
}
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