diff --git a/librf/src/mutex_v2.inl b/librf/src/mutex_v2.inl
index 78d613d..26e70c0 100644
--- a/librf/src/mutex_v2.inl
+++ b/librf/src/mutex_v2.inl
@@ -475,7 +475,7 @@ namespace resumef
 				for (int cnt = rand() % (1 + _mutex.size()); cnt >= 0; --cnt)
 				{
 					std::this_thread::yield();	//还要考虑多线程里运行的情况
-					co_await yield_awaitor{};
+					co_await yield();
 				}
 			}
 			future_t<> _ReturnValue() const;
diff --git a/librf/src/without_deadlock_assemble.inl b/librf/src/without_deadlock_assemble.inl
index 7bef438..71288bb 100644
--- a/librf/src/without_deadlock_assemble.inl
+++ b/librf/src/without_deadlock_assemble.inl
@@ -104,7 +104,6 @@ struct LOCK_ASSEMBLE_NAME(lock_impl)
 	static auto _Lock_nonmember2(_LA& _LkN) ->decltype(_LkN._ReturnValue())
 	{
 		// lock 2 locks, without deadlock, special case for better codegen and reduced metaprogramming for common case
-#if defined(__GNUC__)
 		for (;;)
 		{
 			auto _Result__ = LOCK_ASSEMBLE_AWAIT(_Lock_attempt_small2(_LkN, 0, 1));
@@ -112,12 +111,6 @@ struct LOCK_ASSEMBLE_NAME(lock_impl)
 			_Result__ = LOCK_ASSEMBLE_AWAIT(_Lock_attempt_small2(_LkN, 1, 0));
 			if (!_Result__) break;
 		}
-#else
-		while (LOCK_ASSEMBLE_AWAIT(_Lock_attempt_small2(_LkN, 0, 1)) && 
-			LOCK_ASSEMBLE_AWAIT(_Lock_attempt_small2(_LkN, 1, 0)))
-		{ // keep trying
-		}
-#endif
 	}
 
 	template<_LockAssembleT _LA>
diff --git a/tutorial/test_async_mutex.cpp b/tutorial/test_async_mutex.cpp
index dd368b6..02a49e4 100644
--- a/tutorial/test_async_mutex.cpp
+++ b/tutorial/test_async_mutex.cpp
@@ -158,7 +158,6 @@ static future_t<> resumable_mutex_range_push(size_t idx, mutex_t a, mutex_t b, m
 
 		++g_counter;
 		//std::cout << "push:" << g_counter << " on " << idx << std::endl;
-		
 		//co_await 5ms;
 	}
 }
@@ -174,9 +173,7 @@ static future_t<> resumable_mutex_range_pop(size_t idx, mutex_t a, mutex_t b, mu
 
 		--g_counter;
 		//std::cout << "pop :" << g_counter << " on " << idx << std::endl;
-
 		//co_await 5ms;
-		//co_await mutex_t::unlock(a, b, c);
 	}
 }