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// Check that child trait who only has items via its *parent* trait
// does cause dropck to inject extra region constraints.
#![allow(non_camel_case_types)]
trait Parent { fn foo(&self); }
trait Child: Parent { }
impl Parent for i32 { fn foo(&self) { } }
impl<'a> Parent for &'a D_Child<i32> {
fn foo(&self) {
println!("accessing child value: {}", self.0);
}
}
impl Child for i32 { }
impl<'a> Child for &'a D_Child<i32> { }
struct D_Child<T:Child>(T);
impl <T:Child> Drop for D_Child<T> { fn drop(&mut self) { self.0.foo() } }
fn f_child() {
// `_d` and `d1` are assigned the *same* lifetime by region inference ...
let (_d, d1);
d1 = D_Child(1);
// ... we store a reference to `d1` within `_d` ...
_d = D_Child(&d1);
//~^ ERROR `d1` does not live long enough
// ... dropck *should* complain, because Drop of _d could (and
// does) access the already dropped `d1` via the `foo` method.
}
fn main() {
f_child();
}
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