From d147f78e367386bf63ccb03d453e151e37cfdd81 Mon Sep 17 00:00:00 2001
From: chansuke <chansuke@georepublic.de>
Date: Sat, 24 Oct 2020 18:14:17 +0900
Subject: [PATCH] Fix unsafe operation of wasm32::memory_atomic_notify

---
 library/std/src/sys/wasm/condvar_atomics.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/library/std/src/sys/wasm/condvar_atomics.rs b/library/std/src/sys/wasm/condvar_atomics.rs
index b9133e9fb7db..c2c47910582a 100644
--- a/library/std/src/sys/wasm/condvar_atomics.rs
+++ b/library/std/src/sys/wasm/condvar_atomics.rs
@@ -52,8 +52,9 @@ impl Condvar {
 
     #[inline]
     pub unsafe fn notify_all(&self) {
+        self.cnt.fetch_add(1, SeqCst);
+        // SAFETY: memory_atomic_notify()is always valid
         unsafe {
-            self.cnt.fetch_add(1, SeqCst);
             wasm32::memory_atomic_notify(self.ptr(), u32::MAX); // -1 == "wake everyone"
         }
     }