src/test/ui/rfc-2632-const-trait-impl/const-trait-bound-opt-out/in-impl-trait.rs

#![feature(const_trait_bound_opt_out)]
#![feature(associated_type_bounds)]
#![allow(incomplete_features)]

trait T {}
struct S;
impl T for S {}

fn rpit() -> impl ?const T { S }
//~^ ERROR `?const` is not permitted in `impl Trait`

fn apit(_: impl ?const T) {}
//~^ ERROR `?const` is not permitted in `impl Trait`

fn rpit_assoc_bound() -> impl IntoIterator<Item: ?const T> { Some(S) }
//~^ ERROR `?const` is not permitted in `impl Trait`

fn apit_assoc_bound(_: impl IntoIterator<Item: ?const T>) {}
//~^ ERROR `?const` is not permitted in `impl Trait`

fn main() {}