rust/src/test/compile-fail/borrowck-closures-use-after-free.rs
Felix S. Klock II 270f0eef73 Add : Box<_> or ::Box<_> type annotations to various places.
This is the kind of change that one is expected to need to make to
accommodate overloaded-`box`.

----

Note that this is not *all* of the changes necessary to accommodate
Issue 22181.  It is merely the subset of those cases where there was
already a let-binding in place that made it easy to add the necesasry
type ascription.

(For unnamed intermediate `Box` values, one must go down a different
route; `Box::new` is the option that maximizes portability, but has
potential inefficiency depending on whether the call is inlined.)

----

There is one place worth note, `run-pass/coerce-match.rs`, where I
used an ugly form of `Box<_>` type ascription where I would have
preferred to use `Box::new` to accommodate overloaded-`box`.  I
deliberately did not use `Box::new` here, because that is already done
in coerce-match-calls.rs.

----

Precursor for overloaded-`box` and placement-`in`; see Issue 22181.
2015-03-03 20:29:01 +01:00

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Rust

// Copyright 2014 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.
// Tests that a closure which mutates a local variable
// cannot also be supplied a borrowed version of that
// variable's contents. Issue #11192.
#![feature(box_syntax)]
struct Foo {
x: isize
}
impl Drop for Foo {
fn drop(&mut self) {
println!("drop {}", self.x);
}
}
fn main() {
let mut ptr: Box<_> = box Foo { x: 0 };
let mut test = |foo: &Foo| {
ptr = box Foo { x: ptr.x + 1 };
};
test(&*ptr); //~ ERROR cannot borrow `*ptr`
}