rust/tests/ui/consts/control-flow/interior-mutability.rs
2023-01-11 09:32:08 +00:00

44 lines
865 B
Rust

// Ensure that *any* assignment to the return place of a value with interior mutability
// disqualifies it from promotion.
use std::cell::Cell;
const X: Option<Cell<i32>> = {
let mut x = None;
if false {
x = Some(Cell::new(4));
}
x
};
const Y: Option<Cell<i32>> = {
let mut y = Some(Cell::new(4));
if true {
y = None;
}
y
};
const Z: Option<Cell<i32>> = {
let mut z = None;
let mut i = 0;
while i < 10 {
if i == 8 {
z = Some(Cell::new(4));
}
if i == 9 {
z = None;
}
i += 1;
}
z
};
fn main() {
let x: &'static _ = &X; //~ ERROR temporary value dropped while borrowed
let y: &'static _ = &Y; //~ ERROR temporary value dropped while borrowed
let z: &'static _ = &Z; //~ ERROR temporary value dropped while borrowed
}