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#![allow(dead_code, cenum_impl_drop_cast)]
// check dtor calling order when casting enums.
use std::sync::atomic;
use std::sync::atomic::Ordering;
use std::mem;
enum E {
A = 0,
B = 1,
C = 2
}
static FLAG: atomic::AtomicUsize = atomic::AtomicUsize::new(0);
impl Drop for E {
fn drop(&mut self) {
// avoid dtor loop
unsafe { mem::forget(mem::replace(self, E::B)) };
FLAG.store(FLAG.load(Ordering::SeqCst)+1, Ordering::SeqCst);
}
}
fn main() {
assert_eq!(FLAG.load(Ordering::SeqCst), 0);
{
let e = E::C;
assert_eq!(e as u32, 2);
assert_eq!(FLAG.load(Ordering::SeqCst), 1);
}
assert_eq!(FLAG.load(Ordering::SeqCst), 1);
}
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