mirror of
https://github.com/rust-lang/rust.git
synced 2024-10-31 22:41:50 +00:00
37 lines
642 B
Rust
37 lines
642 B
Rust
// build-pass
|
|
// compile-flags: -Z mir-opt-level=4
|
|
|
|
#![crate_type = "lib"]
|
|
#![feature(lang_items)]
|
|
#![no_std]
|
|
|
|
struct NonNull<T: ?Sized>(*const T);
|
|
|
|
struct Unique<T: ?Sized>(NonNull<T>);
|
|
|
|
#[lang = "owned_box"]
|
|
pub struct Box<T: ?Sized>(Unique<T>);
|
|
|
|
impl<T: ?Sized> Drop for Box<T> {
|
|
fn drop(&mut self) {}
|
|
}
|
|
|
|
#[lang = "box_free"]
|
|
#[inline(always)]
|
|
unsafe fn box_free<T: ?Sized>(ptr: Unique<T>) {
|
|
dealloc(ptr.0.0)
|
|
}
|
|
|
|
#[inline(never)]
|
|
fn dealloc<T: ?Sized>(_: *const T) {}
|
|
|
|
pub struct Foo<T>(T);
|
|
|
|
pub fn foo(a: Option<Box<Foo<usize>>>) -> usize {
|
|
let f = match a {
|
|
None => Foo(0),
|
|
Some(vec) => *vec,
|
|
};
|
|
f.0
|
|
}
|