// Copyright 2012 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. // Tests that auto-ref can't create mutable aliases to immutable memory. struct Foo { x: int } trait Stuff { fn printme(); } impl Stuff for &mut Foo { fn printme() { io::println(fmt!("%d", self.x)); } } fn main() { let x = Foo { x: 3 }; x.printme(); //~ ERROR illegal borrow }