// 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); }