3 files changed, 4 insertions, 11 deletions
diff --git a/library/core/src/future/into_future.rs b/library/core/src/future/into_future.rs
index 649b43387..38c654e76 100644
--- a/library/core/src/future/into_future.rs
+++ b/library/core/src/future/into_future.rs
@@ -99,6 +99,7 @@ use crate::future::Future;
 /// }
 /// ```
 #[stable(feature = "into_future", since = "1.64.0")]
+#[rustc_diagnostic_item = "IntoFuture"]
 pub trait IntoFuture {
     /// The output that the future will produce on completion.
     #[stable(feature = "into_future", since = "1.64.0")]
diff --git a/library/core/src/future/join.rs b/library/core/src/future/join.rs
index 35f0dea06..3f35179dd 100644
--- a/library/core/src/future/join.rs
+++ b/library/core/src/future/join.rs
@@ -4,7 +4,7 @@ use crate::cell::UnsafeCell;
 use crate::future::{poll_fn, Future};
 use crate::mem;
 use crate::pin::Pin;
-use crate::task::{Context, Poll};
+use crate::task::{ready, Context, Poll};
 
 /// Polls multiple futures simultaneously, returning a tuple
 /// of all results once complete.
@@ -118,7 +118,7 @@ macro join_internal {
                             fut
                         })
                     };
-                    // Despite how tempting it may be to `let () = fut.poll(cx).ready()?;`
+                    // Despite how tempting it may be to `let () = ready!(fut.poll(cx));`
                     // doing so would defeat the point of `join!`: to start polling eagerly all
                     // of the futures, to allow parallelizing the waits.
                     done &= fut.poll(cx).is_ready();
@@ -180,7 +180,7 @@ impl<F: Future> Future for MaybeDone<F> {
             // Do not mix match ergonomics with unsafe.
             match *self.as_mut().get_unchecked_mut() {
                 MaybeDone::Future(ref mut f) => {
-                    let val = Pin::new_unchecked(f).poll(cx).ready()?;
+                    let val = ready!(Pin::new_unchecked(f).poll(cx));
                     self.set(Self::Done(val));
                 }
                 MaybeDone::Done(_) => {}
diff --git a/library/core/src/future/mod.rs b/library/core/src/future/mod.rs
index 04f02d47f..089493d37 100644
--- a/library/core/src/future/mod.rs
+++ b/library/core/src/future/mod.rs
@@ -66,11 +66,3 @@ pub unsafe fn get_context<'a, 'b>(cx: ResumeTy) -> &'a mut Context<'b> {
     // that fulfills all the requirements for a mutable reference.
     unsafe { &mut *cx.0.as_ptr().cast() }
 }
-
-#[doc(hidden)]
-#[unstable(feature = "gen_future", issue = "50547")]
-#[inline]
-#[cfg_attr(bootstrap, lang = "identity_future")]
-pub const fn identity_future<O, Fut: Future<Output = O>>(f: Fut) -> Fut {
-    f
-}