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
|
#![feature(extern_types)]
extern "Rust" {
type OpaqueListContents;
}
pub struct ListS<T> {
len: usize,
data: [T; 0],
opaque: OpaqueListContents,
}
pub struct Interned<'a, T>(&'a T);
impl<'a, T> Clone for Interned<'a, T> {
fn clone(&self) -> Self {
*self
}
}
impl<'a, T> Copy for Interned<'a, T> {}
pub struct List<'tcx, T>(Interned<'tcx, ListS<T>>);
//~^ NOTE this field does not implement `Copy`
//~| NOTE the `Copy` impl for `Interned<'tcx, ListS<T>>` requires that `OpaqueListContents: Sized`
impl<'tcx, T> Clone for List<'tcx, T> {
fn clone(&self) -> Self {
*self
}
}
impl<'tcx, T> Copy for List<'tcx, T> {}
//~^ ERROR the trait `Copy` cannot be implemented for this type
fn assert_is_copy<T: Copy>() {}
fn main() {
assert_is_copy::<List<'static, ()>>();
}
|