src/test/run-pass-valgrind/cast-enum-with-dtor.rs

   1 #![allow(dead_code, cenum_impl_drop_cast)]
   2
   3 // check dtor calling order when casting enums.
   4
   5 use std::sync::atomic;
   6 use std::sync::atomic::Ordering;
   7 use std::mem;
   8
   9 enum E {
  10     A = 0,
  11     B = 1,
  12     C = 2
  13 }
  14
  15 static FLAG: atomic::AtomicUsize = atomic::AtomicUsize::new(0);
  16
  17 impl Drop for E {
  18     fn drop(&mut self) {
  19         // avoid dtor loop
  20         unsafe { mem::forget(mem::replace(self, E::B)) };
  21
  22         FLAG.store(FLAG.load(Ordering::SeqCst)+1, Ordering::SeqCst);
  23     }
  24 }
  25
  26 fn main() {
  27     assert_eq!(FLAG.load(Ordering::SeqCst), 0);
  28     {
  29         let e = E::C;
  30         assert_eq!(e as u32, 2);
  31         assert_eq!(FLAG.load(Ordering::SeqCst), 1);
  32     }
  33     assert_eq!(FLAG.load(Ordering::SeqCst), 1);
  34 }