50 lines
1.4 KiB
Rust
50 lines
1.4 KiB
Rust
|
// revisions: no_drop_tracking drop_tracking drop_tracking_mir
|
||
|
|
// [drop_tracking] compile-flags: -Zdrop-tracking
|
||
|
|
// [drop_tracking_mir] compile-flags: -Zdrop-tracking-mir
|
||
|
|
// [no_drop_tracking] known-bug: #105084
|
||
|
|
// [no_drop_tracking] check-pass
|
||
|
|
// [drop_tracking] known-bug: #105084
|
||
|
|
// [drop_tracking] check-pass
|
||
|
|
|
||
|
|
#![feature(generators)]
|
||
|
|
#![feature(generator_clone)]
|
||
|
|
#![feature(generator_trait)]
|
||
|
|
#![feature(box_syntax)]
|
||
|
|
|
||
|
|
use std::ops::Generator;
|
||
|
|
use std::pin::Pin;
|
||
|
|
|
||
|
|
fn copy<T: Copy>(x: T) -> T {
|
||
|
|
x
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
let mut g = || {
|
||
|
|
// This is desuraged as 4 stages:
|
||
|
|
// - allocate a `*mut u8` with `exchange_malloc`;
|
||
|
|
// - create a Box that is ignored for trait computations;
|
||
|
|
// - compute fields (and yields);
|
||
|
|
// - assign to `t`.
|
||
|
|
let t = box (5, yield);
|
||
|
|
drop(t);
|
||
|
|
};
|
||
|
|
|
||
|
|
// Allocate the temporary box.
|
||
|
|
Pin::new(&mut g).resume(());
|
||
|
|
|
||
|
|
// The temporary box is in generator locals.
|
||
|
|
// As it is not taken into account for trait computation,
|
||
|
|
// the generator is `Copy`.
|
||
|
|
let mut h = copy(g);
|
||
|
|
//[drop_tracking_mir]~^ ERROR the trait bound `Box<(i32, ())>: Copy` is not satisfied in
|
||
|
|
|
||
|
|
// We now have 2 boxes with the same backing allocation:
|
||
|
|
// one inside `g` and one inside `h`.
|
||
|
|
// Proceed and drop `t` in `g`.
|
||
|
|
Pin::new(&mut g).resume(());
|
||
|
|
//[drop_tracking_mir]~^ ERROR borrow of moved value: `g`
|
||
|
|
|
||
|
|
// Proceed and drop `t` in `h` -> double free!
|
||
|
|
Pin::new(&mut h).resume(());
|
||
|
|
}
|