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use std::mem::ManuallyDrop;
// Non-copy
struct A;
struct B;
union U {
a: ManuallyDrop<A>,
b: ManuallyDrop<B>,
}
fn main() {
unsafe {
{
let mut u = U { a: ManuallyDrop::new(A) };
let a = u.a;
let a = u.a; //~ ERROR use of moved value: `u`
}
{
let mut u = U { a: ManuallyDrop::new(A) };
let a = u.a;
u.a = ManuallyDrop::new(A);
let a = u.a; // OK
}
{
let mut u = U { a: ManuallyDrop::new(A) };
let a = u.a;
u.b = ManuallyDrop::new(B);
let a = u.a; // OK
}
}
}
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