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#![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` may not be implemented for this type
fn assert_is_copy<T: Copy>() {}
fn main() {
assert_is_copy::<List<'static, ()>>();
}
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