62 lines
1.8 KiB
Rust
62 lines
1.8 KiB
Rust
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// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// revisions: lxl nll
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//[lxl]compile-flags: -Z borrowck=mir -Z two-phase-borrows
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//[nll]compile-flags: -Z borrowck=mir -Z two-phase-borrows -Z nll
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// This is an important corner case pointed out by Niko: one is
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// allowed to initiate a shared borrow during a reservation, but it
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// *must end* before the activation occurs.
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//
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// FIXME: for clarity, diagnostics for these cases might be better off
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// if they specifically said "cannot activate mutable borrow of `x`"
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#![allow(dead_code)]
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fn read(_: &i32) { }
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fn ok() {
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let mut x = 3;
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let y = &mut x;
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{ let z = &x; read(z); }
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*y += 1;
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}
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fn not_ok() {
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let mut x = 3;
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let y = &mut x;
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let z = &x;
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*y += 1;
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//[lxl]~^ ERROR cannot borrow `x` as mutable because it is also borrowed as immutable
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//[nll]~^^ ERROR cannot borrow `x` as mutable because it is also borrowed as immutable
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read(z);
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}
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fn should_be_ok_with_nll() {
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let mut x = 3;
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let y = &mut x;
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let z = &x;
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read(z);
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*y += 1;
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//[lxl]~^ ERROR cannot borrow `x` as mutable because it is also borrowed as immutable
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// (okay with nll today)
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}
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fn should_also_eventually_be_ok_with_nll() {
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let mut x = 3;
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let y = &mut x;
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let _z = &x;
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*y += 1;
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//[lxl]~^ ERROR cannot borrow `x` as mutable because it is also borrowed as immutable
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}
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fn main() { }
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