From 08c16c45972c7dc98f7f0e06d38ea1cb3260394b Mon Sep 17 00:00:00 2001
From: Nur <nurmohammed840@gmail.com>
Date: Sun, 1 Feb 2026 19:31:57 +0600
Subject: [PATCH] local-waker: Add safety docs

---
 local-waker/src/lib.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/local-waker/src/lib.rs b/local-waker/src/lib.rs
index d83a4bc0..bc2f141a 100644
--- a/local-waker/src/lib.rs
+++ b/local-waker/src/lib.rs
@@ -44,12 +44,18 @@ impl LocalWaker {
     #[inline]
     pub fn register(&self, waker: &Waker) -> bool {
         let mut registered = false;
+
+        // SAFETY: `LocalWaker` is `!Send`, threfore this cannot be called from a separate thread.
+        // And this is an unique access before the assignment below.
         if let Some(prev) = unsafe { &*self.waker.get() } {
             if waker.will_wake(prev) {
                 return true;
             }
             registered = true;
         }
+
+        // SAFETY: This can cause data races if called from a separate thread,
+        // but `LocalWaker` is `!Send` + `!Sync` so this won't happen.
         unsafe { *self.waker.get() = Some(waker.clone()) }
         registered
     }