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// run-pass
#![feature(generators)]
#![feature(generator_trait)]
use std::cell::Cell;
use std::mem;
use std::ops::Generator;
use std::pin::Pin;
struct Aligned<'a> {
drop_count: &'a Cell<usize>
}
#[inline(never)]
fn check_align(ptr: *const Aligned) {
assert_eq!(ptr as usize % mem::align_of::<Aligned>(),
0);
}
impl<'a> Drop for Aligned<'a> {
fn drop(&mut self) {
check_align(self);
self.drop_count.set(self.drop_count.get() + 1);
}
}
#[repr(transparent)]
struct NotCopy(#[allow(unused_tuple_struct_fields)] u8);
#[repr(packed)]
struct Packed<'a>(NotCopy, Aligned<'a>);
fn main() {
let drop_count = &Cell::new(0);
{
let mut p = Packed(NotCopy(0), Aligned { drop_count });
p.1 = Aligned { drop_count };
assert_eq!(drop_count.get(), 1);
}
assert_eq!(drop_count.get(), 2);
let drop_count = &Cell::new(0);
let mut g = || {
let mut p = Packed(NotCopy(0), Aligned { drop_count });
let _ = &p;
p.1 = Aligned { drop_count };
assert_eq!(drop_count.get(), 1);
// Test that a generator drop function moves a value from a packed
// struct to a separate local before dropping it. We move out the
// first field to generate and open drop for the second field.
drop(p.0);
yield;
};
Pin::new(&mut g).resume(());
assert_eq!(drop_count.get(), 1);
drop(g);
assert_eq!(drop_count.get(), 2);
}
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