1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
//@revisions: string unit atomic
#![feature(type_alias_impl_trait)]
//! Check that we do not cause cycle errors when trying to
//! obtain information about interior mutability of an opaque type.
//! This used to happen, because when the body-analysis failed, we
//! checked the type instead, but the constant was also defining the
//! hidden type of the opaque type. Thus we ended up relying on the
//! result of our analysis to compute the result of our analysis.
pub type Foo = impl Sized;
#[cfg(string)]
#[define_opaque(Foo)]
const fn foo() -> Foo {
String::new()
}
#[cfg(atomic)]
#[define_opaque(Foo)]
const fn foo() -> Foo {
std::sync::atomic::AtomicU8::new(42)
}
#[cfg(unit)]
#[define_opaque(Foo)]
const fn foo() -> Foo {}
const FOO: Foo = foo();
const BAR: () = {
let _: &'static _ = &FOO;
//[string,atomic,unit]~^ ERROR: destructor of `Foo` cannot be evaluated at compile-time
};
const BAZ: &Foo = &FOO;
//[atomic]~^ ERROR: constants cannot refer to interior mutable data
fn main() {
let _: &'static _ = &FOO;
//[string,atomic,unit]~^ ERROR: temporary value dropped while borrowed
}
|
