src/test/ui/union/union-derive-clone.rs

   1 #![feature(untagged_unions)]
   2
   3 use std::mem::ManuallyDrop;
   4
   5 #[derive(Clone)] //~ ERROR the trait bound `U1: Copy` is not satisfied
   6 union U1 {
   7     a: u8,
   8 }
   9
  10 #[derive(Clone)]
  11 union U2 {
  12     a: u8, // OK
  13 }
  14
  15 impl Copy for U2 {}
  16
  17 #[derive(Clone, Copy)]
  18 union U3 {
  19     a: u8, // OK
  20 }
  21
  22 #[derive(Clone, Copy)]
  23 union U4<T: Copy> {
  24     a: T, // OK
  25 }
  26
  27 #[derive(Clone, Copy)]
  28 union U5<T> {
  29     a: ManuallyDrop<T>, // OK
  30 }
  31
  32 #[derive(Clone)]
  33 struct CloneNoCopy;
  34
  35 fn main() {
  36     let u = U5 { a: ManuallyDrop::new(CloneNoCopy) };
  37     let w = u.clone(); //~ ERROR no method named `clone` found for union `U5<CloneNoCopy>`
  38 }