mirror of https://github.com/rust-lang/rust
58 lines
1.4 KiB
Rust
58 lines
1.4 KiB
Rust
//@ run-pass
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#![feature(coroutines, stmt_expr_attributes)]
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#![feature(coroutine_trait)]
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use std::cell::Cell;
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use std::mem;
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use std::ops::Coroutine;
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use std::pin::Pin;
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struct Aligned<'a> {
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drop_count: &'a Cell<usize>,
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}
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#[inline(never)]
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fn check_align(ptr: *const Aligned) {
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assert_eq!(ptr as usize % mem::align_of::<Aligned>(), 0);
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}
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impl<'a> Drop for Aligned<'a> {
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fn drop(&mut self) {
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check_align(self);
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self.drop_count.set(self.drop_count.get() + 1);
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}
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}
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#[repr(transparent)]
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struct NotCopy(u8);
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#[repr(packed)]
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struct Packed<'a>(NotCopy, Aligned<'a>);
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fn main() {
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let drop_count = &Cell::new(0);
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{
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let mut p = Packed(NotCopy(0), Aligned { drop_count });
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p.1 = Aligned { drop_count };
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assert_eq!(drop_count.get(), 1);
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}
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assert_eq!(drop_count.get(), 2);
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let drop_count = &Cell::new(0);
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let mut g = #[coroutine]
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|| {
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let mut p = Packed(NotCopy(0), Aligned { drop_count });
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let _ = &p;
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p.1 = Aligned { drop_count };
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assert_eq!(drop_count.get(), 1);
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// Test that a coroutine drop function moves a value from a packed
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// struct to a separate local before dropping it. We move out the
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// first field to generate and open drop for the second field.
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drop(p.0);
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yield;
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};
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Pin::new(&mut g).resume(());
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assert_eq!(drop_count.get(), 1);
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drop(g);
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assert_eq!(drop_count.get(), 2);
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}
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