rust/tests/pass/dst-raw.rs
2022-06-20 15:39:46 -07:00

95 lines
1.9 KiB
Rust

// Test DST raw pointers
trait Trait {
fn foo(&self) -> isize;
}
struct A {
f: isize,
}
impl Trait for A {
fn foo(&self) -> isize {
self.f
}
}
struct Foo<T: ?Sized> {
f: T,
}
pub fn main() {
// raw trait object
let x = A { f: 42 };
let z: *const dyn Trait = &x;
let r = unsafe { (&*z).foo() };
assert_eq!(r, 42);
// raw DST struct
let p = Foo { f: A { f: 42 } };
let o: *const Foo<dyn Trait> = &p;
let r = unsafe { (&*o).f.foo() };
assert_eq!(r, 42);
// raw slice
let a: *const [_] = &[1, 2, 3];
unsafe {
let b = (*a)[2];
assert_eq!(b, 3);
let len = (*a).len();
assert_eq!(len, 3);
}
// raw slice with explicit cast
let a = &[1, 2, 3] as *const [i32];
unsafe {
let b = (*a)[2];
assert_eq!(b, 3);
let len = (*a).len();
assert_eq!(len, 3);
}
// raw DST struct with slice
let c: *const Foo<[_]> = &Foo { f: [1, 2, 3] };
unsafe {
let b = (&*c).f[0];
assert_eq!(b, 1);
let len = (&*c).f.len();
assert_eq!(len, 3);
}
// all of the above with *mut
let mut x = A { f: 42 };
let z: *mut dyn Trait = &mut x;
let r = unsafe { (&*z).foo() };
assert_eq!(r, 42);
let mut p = Foo { f: A { f: 42 } };
let o: *mut Foo<dyn Trait> = &mut p;
let r = unsafe { (&*o).f.foo() };
assert_eq!(r, 42);
let a: *mut [_] = &mut [1, 2, 3];
unsafe {
let b = (*a)[2];
assert_eq!(b, 3);
let len = (*a).len();
assert_eq!(len, 3);
}
let a = &mut [1, 2, 3] as *mut [i32];
unsafe {
let b = (*a)[2];
assert_eq!(b, 3);
let len = (*a).len();
assert_eq!(len, 3);
}
let c: *mut Foo<[_]> = &mut Foo { f: [1, 2, 3] };
unsafe {
let b = (&*c).f[0];
assert_eq!(b, 1);
let len = (&*c).f.len();
assert_eq!(len, 3);
}
}