rust/src/test/compile-fail/retslot-cast.rs
Niko Matsakis 5f5ed62298 Remove subtyping for object types and replace with an *upcast* coercion.
This upcast coercion currently preserves the vtable for the object, but
eventually it can be used to create a derived vtable. The upcast
coercion is not introduced into method dispatch; see comment on #18737
for information about why. Fixes #18737.
2015-03-17 08:34:25 -04:00

32 lines
1.2 KiB
Rust

// Copyright 2015 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.
#![feature(rustc_attrs)]
#![allow(warnings)]
pub fn fail(x: Option<& (Iterator+Send)>) -> Option<&Iterator> {
// This call used to trigger an LLVM assertion because the return
// slot had type "Option<&Iterator>"* instead of
// "Option<&(Iterator+Send)>"* -- but this now yields a
// compilation error and I'm not sure how to create a comparable
// test. To ensure that this PARTICULAR failure doesn't occur
// again, though, I've left this test here, so if this ever starts
// to compile again, we can adjust the test appropriately (clearly
// it should never ICE...). -nmatsakis
inner(x) //~ ERROR mismatched types
}
pub fn inner(x: Option<& (Iterator+Send)>) -> Option<&(Iterator+Send)> {
x
}
#[rustc_error]
fn main() {}