rust/src/test/ui/issues/issue-17263.rs
2018-11-05 15:26:02 +01:00

36 lines
1.3 KiB
Rust

// This checks diagnostic quality for cases where AST-borrowck treated
// `Box<T>` as other types (see rust-lang/rfcs#130). NLL again treats
// `Box<T>` specially. We capture the differences via revisions.
// revisions: ast nll
//[ast]compile-flags: -Z borrowck=ast
//[nll]compile-flags: -Z borrowck=migrate -Z two-phase-borrows
// don't worry about the --compare-mode=nll on this test.
// ignore-compare-mode-nll
#![feature(box_syntax, rustc_attrs)]
struct Foo { a: isize, b: isize }
#[rustc_error] // rust-lang/rust#49855
fn main() { //[nll]~ ERROR compilation successful
let mut x: Box<_> = box Foo { a: 1, b: 2 };
let (a, b) = (&mut x.a, &mut x.b);
//[ast]~^ ERROR cannot borrow `x` (via `x.b`) as mutable more than once at a time
let mut foo: Box<_> = box Foo { a: 1, b: 2 };
let (c, d) = (&mut foo.a, &foo.b);
//[ast]~^ ERROR cannot borrow `foo` (via `foo.b`) as immutable
// We explicitly use the references created above to illustrate
// that NLL is accepting this code *not* because of artificially
// short lifetimes, but rather because it understands that all the
// references are of disjoint parts of memory.
use_imm(d);
use_mut(c);
use_mut(b);
use_mut(a);
}
fn use_mut<T>(_: &mut T) { }
fn use_imm<T>(_: &T) { }