2 files changed, 7 insertions, 4 deletions
diff --git a/library/alloc/src/boxed.rs b/library/alloc/src/boxed.rs
index e0f94428cfa..23b85fbd4eb 100644
--- a/library/alloc/src/boxed.rs
+++ b/library/alloc/src/boxed.rs
@@ -1985,7 +1985,8 @@ impl<Args: Tuple, F: Fn<Args> + ?Sized, A: Allocator> Fn<Args> for Box<F, A> {
     }
 }
 
-#[unstable(feature = "async_fn_traits", issue = "none")]
+#[cfg_attr(bootstrap, unstable(feature = "async_closure", issue = "62290"))]
+#[cfg_attr(not(bootstrap), stable(feature = "async_closure", since = "CURRENT_RUSTC_VERSION"))]
 impl<Args: Tuple, F: AsyncFnOnce<Args> + ?Sized, A: Allocator> AsyncFnOnce<Args> for Box<F, A> {
     type Output = F::Output;
     type CallOnceFuture = F::CallOnceFuture;
@@ -1995,7 +1996,8 @@ impl<Args: Tuple, F: AsyncFnOnce<Args> + ?Sized, A: Allocator> AsyncFnOnce<Args>
     }
 }
 
-#[unstable(feature = "async_fn_traits", issue = "none")]
+#[cfg_attr(bootstrap, unstable(feature = "async_closure", issue = "62290"))]
+#[cfg_attr(not(bootstrap), stable(feature = "async_closure", since = "CURRENT_RUSTC_VERSION"))]
 impl<Args: Tuple, F: AsyncFnMut<Args> + ?Sized, A: Allocator> AsyncFnMut<Args> for Box<F, A> {
     type CallRefFuture<'a>
         = F::CallRefFuture<'a>
@@ -2007,7 +2009,8 @@ impl<Args: Tuple, F: AsyncFnMut<Args> + ?Sized, A: Allocator> AsyncFnMut<Args> f
     }
 }
 
-#[unstable(feature = "async_fn_traits", issue = "none")]
+#[cfg_attr(bootstrap, unstable(feature = "async_closure", issue = "62290"))]
+#[cfg_attr(not(bootstrap), stable(feature = "async_closure", since = "CURRENT_RUSTC_VERSION"))]
 impl<Args: Tuple, F: AsyncFn<Args> + ?Sized, A: Allocator> AsyncFn<Args> for Box<F, A> {
     extern "rust-call" fn async_call(&self, args: Args) -> Self::CallRefFuture<'_> {
         F::async_call(self, args)
diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs
index 78cdeeb2866..40759cb0ba8 100644
--- a/library/alloc/src/lib.rs
+++ b/library/alloc/src/lib.rs
@@ -91,6 +91,7 @@
 //
 // Library features:
 // tidy-alphabetical-start
+#![cfg_attr(bootstrap, feature(async_closure))]
 #![cfg_attr(test, feature(str_as_str))]
 #![feature(alloc_layout_extra)]
 #![feature(allocator_api)]
@@ -99,7 +100,6 @@
 #![feature(array_windows)]
 #![feature(ascii_char)]
 #![feature(assert_matches)]
-#![feature(async_closure)]
 #![feature(async_fn_traits)]
 #![feature(async_iterator)]
 #![feature(box_uninit_write)]