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use std::mem::ManuallyDrop;
#[derive(Clone)] //~ ERROR the trait bound `U1: Copy` is not satisfied
union U1 {
a: u8,
}
#[derive(Clone)]
union U2 {
a: u8, // OK
}
impl Copy for U2 {}
#[derive(Clone, Copy)]
union U3 {
a: u8, // OK
}
#[derive(Clone, Copy)]
union U4<T: Copy> {
a: T, // OK
}
#[derive(Clone, Copy)]
union U5<T> {
a: ManuallyDrop<T>, // OK
}
#[derive(Clone)]
struct CloneNoCopy;
fn main() {
let u = U5 { a: ManuallyDrop::new(CloneNoCopy) };
let w = u.clone(); //~ ERROR the method
}
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