File: drop-struct-as-object.rs

package info (click to toggle)
rustc 1.88.0%2Bdfsg1-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 934,128 kB
  • sloc: xml: 158,127; python: 36,062; javascript: 19,855; sh: 19,700; cpp: 18,947; ansic: 12,993; asm: 4,792; makefile: 690; lisp: 29; perl: 29; ruby: 19; sql: 11
file content (39 lines) | stat: -rw-r--r-- 748 bytes parent folder | download | duplicates (14)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
//@ run-pass
#![allow(unused_variables)]
#![allow(non_upper_case_globals)]

// Test that destructor on a struct runs successfully after the struct
// is boxed and converted to an object.

// FIXME(static_mut_refs): this could use an atomic
#![allow(static_mut_refs)]

static mut value: usize = 0;

struct Cat {
    name : usize,
}

trait Dummy {
    fn get(&self) -> usize; //~ WARN method `get` is never used
}

impl Dummy for Cat {
    fn get(&self) -> usize { self.name }
}

impl Drop for Cat {
    fn drop(&mut self) {
        unsafe { value = self.name; }
    }
}

pub fn main() {
    {
        let x = Box::new(Cat {name: 22});
        let nyan: Box<dyn Dummy> = x as Box<dyn Dummy>;
    }
    unsafe {
        assert_eq!(value, 22);
    }
}