rust/src/test/compile-fail/regions-free-region-ordering-caller.rs
Niko Matsakis 3322595e89 Reason about nested free variables that appear in a function
signature.  In a nutshell, the idea is to (1) report an error if, for
a region pointer `'a T`, the lifetime `'a` is longer than any
lifetimes that appear in `T` (in other words, if a borrowed pointer
outlives any portion of its contents) and then (2) use this to assume
that in a function like `fn(self: &'a &'b T)`, the relationship `'a <=
'b` holds. This is needed for #5656.  Fixes #5728.
2013-04-10 07:52:46 -07:00

40 lines
1.4 KiB
Rust

// 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 <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.
// Test various ways to construct a pointer with a longer lifetime
// than the thing it points at and ensure that they result in
// errors. See also regions-free-region-ordering-callee.rs
struct Paramd<'self> { x: &'self uint }
fn call1<'a>(x: &'a uint) {
let y: uint = 3;
let z: &'a &'blk uint = &(&y);
//~^ ERROR pointer has a longer lifetime than the data it references
}
fn call2<'a, 'b>(a: &'a uint, b: &'b uint) {
let z: Option<&'b &'a uint> = None;
//~^ ERROR pointer has a longer lifetime than the data it references
}
fn call3<'a, 'b>(a: &'a uint, b: &'b uint) {
let y: Paramd<'a> = Paramd { x: a };
let z: Option<&'b Paramd<'a>> = None;
//~^ ERROR pointer has a longer lifetime than the data it references
}
fn call4<'a, 'b>(a: &'a uint, b: &'b uint) {
let z: Option<&fn(&'a &'b uint)> = None;
//~^ ERROR pointer has a longer lifetime than the data it references
}
fn main() {}