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//@ revisions: stable unstable
#![cfg_attr(unstable, feature(unstable))] // The feature from the ./auxiliary/staged-api.rs file.
#![feature(const_trait_impl, effects)]
#![feature(staged_api)]
#![stable(feature = "rust1", since = "1.0.0")]
//@ aux-build: staged-api.rs
extern crate staged_api;
use staged_api::*;
#[stable(feature = "rust1", since = "1.0.0")]
pub struct Foo;
#[stable(feature = "rust1", since = "1.0.0")]
#[cfg_attr(unstable, rustc_const_unstable(feature = "foo", issue = "none"))]
#[cfg_attr(stable, rustc_const_stable(feature = "foo", since = "1.0.0"))]
impl const MyTrait for Foo {
//[stable]~^ ERROR trait implementations cannot be const stable yet
fn func() {}
}
// Const stability has no impact on usage in non-const contexts.
fn non_const_context() {
Unstable::func();
Foo::func();
}
#[unstable(feature = "none", issue = "none")]
const fn const_context() {
Unstable::func();
//[stable]~^ ERROR not yet stable as a const fn
Foo::func();
//[unstable]~^ ERROR not yet stable as a const fn
// ^ fails, because the `foo` feature is not active
}
#[stable(feature = "rust1", since = "1.0.0")]
#[cfg_attr(unstable, rustc_const_unstable(feature = "foo", issue = "none"))]
pub const fn const_context_not_const_stable() {
//[stable]~^ ERROR function has missing const stability attribute
Unstable::func();
//[stable]~^ ERROR not yet stable as a const fn
Foo::func();
//[unstable]~^ ERROR not yet stable as a const fn
// ^ fails, because the `foo` feature is not active
}
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "cheese", since = "1.0.0")]
const fn stable_const_context() {
Unstable::func();
//~^ ERROR not yet stable as a const fn
Foo::func();
//[unstable]~^ ERROR not yet stable as a const fn
const_context_not_const_stable()
//[unstable]~^ ERROR not yet stable as a const fn
}
fn main() {}
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