Fixed case where borrowed value lives until after scope

This commit is contained in:
David Wood 2017-12-10 20:36:42 +00:00
parent 52442d4d8a
commit baf68d3a37
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GPG Key ID: 01760B4F9F53F154
3 changed files with 69 additions and 8 deletions

View File

@ -356,14 +356,30 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
match &self.describe_place(&borrow.place) {
Some(description) => {
let mut err = self.tcx.path_does_not_live_long_enough(
borrow_span, &format!("`{}`", description), Origin::Mir);
err.span_label(borrow_span, "does not live long enough");
err.span_label(drop_span, "borrowed value only lives until here");
self.tcx.note_and_explain_region(scope_tree, &mut err,
"borrowed value must be valid for ",
borrow.region, "...");
err.emit();
match borrow.region {
RegionKind::ReScope(_) => {
let mut err = self.tcx.path_does_not_live_long_enough(
drop_span, &format!("`{}`", description), Origin::Mir);
err.span_label(borrow_span, "borrow occurs here");
err.span_label(drop_span,
format!("`{}` dropped here while still borrowed",
description));
if let Some(end) = end_span {
err.span_label(end, "borrowed value needs to live until here");
}
err.emit();
},
_ => {
let mut err = self.tcx.path_does_not_live_long_enough(
borrow_span, &format!("`{}`", description), Origin::Mir);
err.span_label(borrow_span, "does not live long enough");
err.span_label(drop_span, "borrowed value only lives until here");
self.tcx.note_and_explain_region(scope_tree, &mut err,
"borrowed value must be valid for ",
borrow.region, "...");
err.emit();
}
}
},
None => {
match borrow.region {

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@ -0,0 +1,21 @@
// Copyright 2016 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.
// compile-flags: -Z emit-end-regions -Z borrowck=compare
fn main() {
let y = {
let mut z = 0;
&mut z
};
//~^ ERROR `z` does not live long enough (Ast) [E0597]
//~| ERROR `z` does not live long enough (Mir) [E0597]
println!("{}", y);
}

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@ -0,0 +1,24 @@
error[E0597]: `z` does not live long enough (Ast)
--> $DIR/issue-46471-1.rs:17:5
|
16 | &mut z
| - borrow occurs here
17 | };
| ^ `z` dropped here while still borrowed
...
21 | }
| - borrowed value needs to live until here
error[E0597]: `z` does not live long enough (Mir)
--> $DIR/issue-46471-1.rs:17:6
|
16 | &mut z
| ------ borrow occurs here
17 | };
| ^ `z` dropped here while still borrowed
...
21 | }
| - borrowed value needs to live until here
error: aborting due to 2 previous errors