rust/src/test/ui/nll/drop-no-may-dangle.rs
csmoe 8d77c7c037 retrieve ty info from place_ty
describe index with _
2018-12-27 17:25:45 +08:00

33 lines
819 B
Rust

// Basic test for liveness constraints: the region (`R1`) that appears
// in the type of `p` must include everything until `p` is dropped
// because of destructor. (Note that the stderr also identifies this
// destructor in the error message.)
// compile-flags:-Zborrowck=mir
#![allow(warnings)]
#![feature(dropck_eyepatch)]
fn use_x(_: usize) -> bool { true }
fn main() {
let mut v = [1, 2, 3];
let p: WrapMayNotDangle<&usize> = WrapMayNotDangle { value: &v[0] };
if true {
use_x(*p.value);
} else {
use_x(22);
v[0] += 1; //~ ERROR cannot assign to `v[_]` because it is borrowed
}
v[0] += 1; //~ ERROR cannot assign to `v[_]` because it is borrowed
}
struct WrapMayNotDangle<T> {
value: T
}
impl<T> Drop for WrapMayNotDangle<T> {
fn drop(&mut self) { }
}