rust/tests/compile-fail/box-cell-alias.rs
2022-04-01 14:10:24 -04:00

19 lines
503 B
Rust

// compile-flags: -Zmiri-strict-provenance
// Taken from <https://github.com/rust-lang/unsafe-code-guidelines/issues/194#issuecomment-520934222>.
use std::cell::Cell;
fn helper(val: Box<Cell<u8>>, ptr: *const Cell<u8>) -> u8 {
val.set(10);
unsafe { (*ptr).set(20); } //~ ERROR does not exist in the borrow stack
val.get()
}
fn main() {
let val: Box<Cell<u8>> = Box::new(Cell::new(25));
let ptr: *const Cell<u8> = &*val;
let res = helper(val, ptr);
assert_eq!(res, 20);
}