src/test/compile-fail/borrowck/borrowck-union-move-assign.rs

   1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 #![feature(untagged_unions)]
  12
  13 // Non-copy
  14 struct A;
  15 struct B;
  16
  17 union U {
  18     a: A,
  19     b: B,
  20 }
  21
  22 fn main() {
  23     unsafe {
  24         {
  25             let mut u = U { a: A };
  26             let a = u.a;
  27             let a = u.a; //~ ERROR use of moved value: `u.a`
  28         }
  29         {
  30             let mut u = U { a: A };
  31             let a = u.a;
  32             u.a = A;
  33             let a = u.a; // OK
  34         }
  35         {
  36             let mut u = U { a: A };
  37             let a = u.a;
  38             u.b = B;
  39             let a = u.a; // OK
  40         }
  41     }
  42 }