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//@ run-pass
#![allow(dead_code)]
// Check that drop elaboration clears the "master" discriminant
// drop flag even if it protects no fields.
struct Good(usize);
impl Drop for Good {
#[inline(never)]
fn drop(&mut self) {
println!("dropping Good({})", self.0);
}
}
struct Void;
impl Drop for Void {
#[inline(never)]
fn drop(&mut self) {
panic!("Suddenly, a Void appears.");
}
}
enum E {
Never(Void),
Fine(Good)
}
fn main() {
let mut go = true;
loop {
let next;
match go {
true => next = E::Fine(Good(123)),
false => return,
}
match next {
E::Never(_) => return,
E::Fine(_good) => go = false,
}
// `next` is dropped and StorageDead'd here. We must reset the
// discriminant's drop flag to avoid random variants being
// dropped.
}
}
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