blob: 74c8ff370f98b8ae356769271e51ab8111b4ed3a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
|
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![feature(conservative_impl_trait)]
use std::fmt;
fn foo() -> Box<impl fmt::Debug+?Sized> {
let x : Box<[u8]> = Box::new([0]);
x
}
fn bar() -> Box<impl fmt::Debug+?Sized> {
let y: Box<fmt::Debug> = Box::new([0]);
y
}
fn main() {
let f = foo();
let b = bar();
// this is an `*mut [u8]` in practice
let f_raw : *mut _ = Box::into_raw(f);
// this is an `*mut fmt::Debug` in practice
let mut b_raw = Box::into_raw(b);
// ... and they should not be mixable
b_raw = f_raw as *mut _; //~ ERROR is invalid
}
|
