rust/src/test/run-pass/issue-4759.rs

// Copyright 2013 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.

#![allow(unknown_features)]
#![feature(box_syntax)]

struct T { a: Box<int> }

trait U {
    fn f(self);
}

impl U for Box<int> {
    fn f(self) { }
}

pub fn main() {
    let T { a: a } = T { a: box 0 };
    a.f();
}