Dropping NonSend resources is unsound #3310
Description
Bevy version
0.5 (and present main)
What you did
use bevy::prelude::*;
use std::cell::UnsafeCell;
struct MyNonSend(UnsafeCell<()>);
impl Drop for MyNonSend {
fn drop(&mut self) {
dbg!("dropped");
}
}
fn main() {
let mut world = World::new();
world.insert_non_send(MyNonSend(UnsafeCell::new(())));
std::thread::spawn(move || {
drop(world);
})
.join()
.unwrap();
}What you expected to happen
The NonSend resource is dropped correctly.
What actually happened
"Dropped" is printed.
Additional information
Full credit to @TheRawMeatball, @jakobhellermann @BoxyUwU and @DJMcNab. Blame them; I'm just the ticketmaster!