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|
// run-rustfix
#![deny(rust_2021_incompatible_closure_captures)]
//~^ NOTE: the lint level is defined here
#![feature(rustc_attrs)]
#![allow(unused)]
use std::sync::Mutex;
#[rustc_insignificant_dtor]
struct InsignificantDropPoint {
x: i32,
y: Mutex<i32>,
}
impl Drop for InsignificantDropPoint {
fn drop(&mut self) {}
}
struct SigDrop;
impl Drop for SigDrop {
fn drop(&mut self) {}
}
#[rustc_insignificant_dtor]
struct GenericStruct<T>(T, T);
impl<T> Drop for GenericStruct<T> {
fn drop(&mut self) {}
}
struct Wrapper<T>(GenericStruct<T>, i32);
// `SigDrop` implements drop and therefore needs to be migrated.
fn significant_drop_needs_migration() {
let t = (SigDrop {}, SigDrop {});
let c = || {
//~^ ERROR: drop order
//~| NOTE: for more information, see
//~| HELP: add a dummy let to cause `t` to be fully captured
let _t = t.0;
//~^ NOTE: in Rust 2018, this closure captures all of `t`, but in Rust 2021, it will only capture `t.0`
};
c();
}
//~^ NOTE: in Rust 2018, `t` is dropped here, but in Rust 2021, only `t.0` will be dropped here as part of the closure
// Even if a type implements an insignificant drop, if it's
// elements have a significant drop then the overall type is
// consdered to have an significant drop. Since the elements
// of `GenericStruct` implement drop, migration is required.
fn generic_struct_with_significant_drop_needs_migration() {
let t = Wrapper(GenericStruct(SigDrop {}, SigDrop {}), 5);
// move is used to force i32 to be copied instead of being a ref
let c = move || {
//~^ ERROR: drop order
//~| NOTE: for more information, see
//~| HELP: add a dummy let to cause `t` to be fully captured
let _t = t.1;
//~^ NOTE: in Rust 2018, this closure captures all of `t`, but in Rust 2021, it will only capture `t.1`
};
c();
}
//~^ NOTE: in Rust 2018, `t` is dropped here, but in Rust 2021, only `t.1` will be dropped here as part of the closure
fn main() {
significant_drop_needs_migration();
generic_struct_with_significant_drop_needs_migration();
}
|
