93 lines
2.5 KiB
Rust
93 lines
2.5 KiB
Rust
// edition:2021
|
|
|
|
// check-pass
|
|
#![allow(unreachable_code)]
|
|
#![warn(unused)]
|
|
#![allow(dead_code)]
|
|
|
|
#[derive(Debug)]
|
|
struct Point {
|
|
x: i32,
|
|
y: i32,
|
|
}
|
|
|
|
pub fn f() {
|
|
let mut a = 1;
|
|
let mut c = Point{ x:1, y:0 };
|
|
|
|
// Captured by value, but variable is dead on entry.
|
|
(move || {
|
|
// This will not trigger a warning for unused variable as
|
|
// c.x will be treated as a Non-tracked place
|
|
c.x = 1;
|
|
println!("{}", c.x);
|
|
a = 1; //~ WARN value captured by `a` is never read
|
|
println!("{}", a);
|
|
})();
|
|
|
|
// Read and written to, but never actually used.
|
|
(move || {
|
|
// This will not trigger a warning for unused variable as
|
|
// c.x will be treated as a Non-tracked place
|
|
c.x += 1;
|
|
a += 1; //~ WARN unused variable: `a`
|
|
})();
|
|
|
|
(move || {
|
|
println!("{}", c.x);
|
|
// Value is read by closure itself on later invocations.
|
|
// This will not trigger a warning for unused variable as
|
|
// c.x will be treated as a Non-tracked place
|
|
c.x += 1;
|
|
println!("{}", a);
|
|
a += 1;
|
|
})();
|
|
let b = Box::new(42);
|
|
(move || {
|
|
println!("{}", c.x);
|
|
// Never read because this is FnOnce closure.
|
|
// This will not trigger a warning for unused variable as
|
|
// c.x will be treated as a Non-tracked place
|
|
c.x += 1;
|
|
println!("{}", a);
|
|
a += 1; //~ WARN value assigned to `a` is never read
|
|
drop(b);
|
|
})();
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
struct MyStruct<'a> {
|
|
x: Option<& 'a str>,
|
|
y: i32,
|
|
}
|
|
|
|
pub fn nested() {
|
|
let mut a : Option<& str>;
|
|
a = None;
|
|
let mut b : Option<& str>;
|
|
b = None;
|
|
let mut d = MyStruct{ x: None, y: 1};
|
|
let mut e = MyStruct{ x: None, y: 1};
|
|
(|| {
|
|
(|| {
|
|
// This will not trigger a warning for unused variable as
|
|
// d.x will be treated as a Non-tracked place
|
|
d.x = Some("d1");
|
|
d.x = Some("d2");
|
|
a = Some("d1"); //~ WARN value assigned to `a` is never read
|
|
a = Some("d2");
|
|
})();
|
|
(move || {
|
|
// This will not trigger a warning for unused variable as
|
|
//e.x will be treated as a Non-tracked place
|
|
e.x = Some("e1");
|
|
e.x = Some("e2");
|
|
b = Some("e1"); //~ WARN value assigned to `b` is never read
|
|
//~| WARN unused variable: `b`
|
|
b = Some("e2"); //~ WARN value assigned to `b` is never read
|
|
})();
|
|
})();
|
|
}
|
|
|
|
fn main() {}
|