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
|
//@ build-fail
//@ revisions: normal mir-opt
//@ [mir-opt]compile-flags: -Zmir-opt-level=4
trait C {
const BOO: usize;
}
trait Foo<T> {
const BAR: usize;
}
struct A<T>(T);
impl<T: C> Foo<T> for A<T> {
const BAR: usize = [5, 6, 7][T::BOO]; //~ ERROR evaluation of `<A<()> as Foo<()>>::BAR` failed
}
fn foo<T: C>() -> &'static usize {
&<A<T> as Foo<T>>::BAR //~ constant
}
impl C for () {
const BOO: usize = 42;
}
impl C for u32 {
const BOO: usize = 1;
}
fn main() {
println!("{:x}", foo::<()>() as *const usize as usize);
println!("{:x}", foo::<u32>() as *const usize as usize);
println!("{:x}", foo::<()>());
println!("{:x}", foo::<u32>());
}
|
