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//@ run-pass
#![allow(dead_code)]
#![allow(non_upper_case_globals)]
// In theory, it doesn't matter what order destructors are run in for rust
// because we have explicit ownership of values meaning that there's no need to
// run one before another. With unsafe code, however, there may be a safe
// interface which relies on fields having their destructors run in a particular
// order. At the time of this writing, std::rt::sched::Scheduler is an example
// of a structure which contains unsafe handles to FFI-like types, and the
// destruction order of the fields matters in the sense that some handles need
// to get destroyed before others.
//
// In C++, destruction order happens bottom-to-top in order of field
// declarations, but we currently run them top-to-bottom. I don't think the
// order really matters that much as long as we define what it is.
struct A;
struct B;
struct C {
a: A,
b: B,
}
static mut hit: bool = false;
impl Drop for A {
fn drop(&mut self) {
unsafe {
assert!(!hit);
hit = true;
}
}
}
impl Drop for B {
fn drop(&mut self) {
unsafe {
assert!(hit);
}
}
}
pub fn main() {
let _c = C { a: A, b: B };
}
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