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// check that misc. method calls are well-formed
use std::marker::PhantomData;
use std::ops::{Deref, Shl};
#[derive(Copy, Clone)]
struct S<'a, 'b: 'a> {
marker: PhantomData<&'a &'b ()>,
bomb: Option<&'b u32>
}
type S2<'a> = S<'a, 'a>;
impl<'a, 'b> S<'a, 'b> {
fn transmute_inherent(&self, a: &'b u32) -> &'a u32 {
a
}
}
fn return_dangling_pointer_inherent(s: S2) -> &u32 {
let s = s;
s.transmute_inherent(&mut 42) //~ ERROR cannot return value referencing temporary value
}
impl<'a, 'b> Deref for S<'a, 'b> {
type Target = &'a u32;
fn deref(&self) -> &&'a u32 {
self.bomb.as_ref().unwrap()
}
}
fn return_dangling_pointer_coerce(s: S2) -> &u32 {
let four = 4;
let mut s = s;
s.bomb = Some(&four);
&s //~ ERROR cannot return value referencing local variable `four`
}
fn return_dangling_pointer_unary_op(s: S2) -> &u32 {
let four = 4;
let mut s = s;
s.bomb = Some(&four);
&*s //~ ERROR cannot return value referencing local variable `four`
}
impl<'a, 'b> Shl<&'b u32> for S<'a, 'b> {
type Output = &'a u32;
fn shl(self, t: &'b u32) -> &'a u32 { t }
}
fn return_dangling_pointer_binary_op(s: S2) -> &u32 {
let s = s;
s << &mut 3 //~ ERROR cannot return value referencing temporary value
}
fn return_dangling_pointer_method(s: S2) -> &u32 {
let s = s;
s.shl(&mut 3) //~ ERROR cannot return value referencing temporary value
}
fn return_dangling_pointer_ufcs(s: S2) -> &u32 {
let s = s;
S2::shl(s, &mut 3) //~ ERROR cannot return value referencing temporary value
}
fn main() {
let s = S { marker: PhantomData, bomb: None };
let _inherent_dp = return_dangling_pointer_inherent(s);
let _coerce_dp = return_dangling_pointer_coerce(s);
let _unary_dp = return_dangling_pointer_unary_op(s);
let _binary_dp = return_dangling_pointer_binary_op(s);
let _method_dp = return_dangling_pointer_method(s);
let _ufcs_dp = return_dangling_pointer_ufcs(s);
}
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