Rust transmute/ownership isolated drop case

droptest.rs

use std::mem;

struct Val {
    value: i32
}

impl Val {
    fn new(value: i32) -> Val {
        println!("Created {}", value);
        Val { value: value }
    }
}

impl Drop for Val {
    fn drop(&mut self) {
        println!("Destroyed {}", self.value);
    }
}

fn main() {
    let val = Box::new(Val::new(32));
    let ptr: *mut Val = unsafe { mem::transmute(val) };
    let _: Box<Val> = unsafe { mem::transmute(ptr) };
}

output

~/dev/projects/droptest $ cargo run
   Compiling droptest v0.1.0 (file:///Users/yupferris/dev/projects/droptest)
     Running `target/debug/droptest`
Created 32
Destroyed 32