rust/tests/ui/borrowck/borrowck-loan-of-static-data-issue-27616.rs
2023-01-11 09:32:08 +00:00

25 lines
533 B
Rust

use std::mem;
fn leak<T>(mut b: Box<T>) -> &'static mut T {
// isn't this supposed to be safe?
let inner = &mut *b as *mut _;
mem::forget(b);
unsafe { &mut *inner }
}
fn evil(mut s: &'static mut String)
{
// create alias
let alias: &'static mut String = s;
let inner: &str = &alias;
// free value
*s = String::new(); //~ ERROR cannot assign
let _spray = "0wned".to_owned();
// ... and then use it
println!("{}", inner);
}
fn main() {
evil(leak(Box::new("hello".to_owned())));
}