rt: Allow concurrent `block_on`'s with basic_scheduler (#2804)

2 files changed, 14 insertions, 0 deletions

diff --git a/tokio/src/sync/mod.rs b/tokio/src/sync/mod.rs
index 1a584383..2e674136 100644
--- a/tokio/src/sync/mod.rs
+++ b/tokio/src/sync/mod.rs
@@ -457,6 +457,13 @@ cfg_sync! {
 }
 
 cfg_not_sync! {
+    cfg_rt_core! {
+        mod notify;
+        pub(crate) use notify::Notify;
+    }
+}
+
+cfg_not_sync! {
     cfg_atomic_waker_impl! {
         mod task;
         pub(crate) use task::AtomicWaker;
diff --git a/tokio/src/sync/notify.rs b/tokio/src/sync/notify.rs
index 56bbc51b..d319e8aa 100644
--- a/tokio/src/sync/notify.rs
+++ b/tokio/src/sync/notify.rs
@@ -1,3 +1,10 @@
+// Allow `unreachable_pub` warnings when sync is not enabled
+// due to the usage of `Notify` within the `rt-core` feature set.
+// When this module is compiled with `sync` enabled we will warn on
+// this lint. When `rt-core` is enabled we use `pub(crate)` which
+// triggers this warning but it is safe to ignore in this case.
+#![cfg_attr(not(feature = "sync"), allow(unreachable_pub, dead_code))]
+
 use crate::loom::sync::atomic::AtomicU8;
 use crate::loom::sync::Mutex;
 use crate::util::linked_list::{self, LinkedList};