diff --git a/asio/src/tests/unit/windows/object_handle.cpp b/asio/src/tests/unit/windows/object_handle.cpp
index 32a836ef..b24241b3 100644
--- a/asio/src/tests/unit/windows/object_handle.cpp
+++ b/asio/src/tests/unit/windows/object_handle.cpp
@@ -68,7 +68,7 @@ void test()
 #if !defined(ASIO_NO_DEPRECATED)
     io_context& ioc_ref = handle1.get_io_context();
     (void)ioc_ref;
-#endif !defined(ASIO_NO_DEPRECATED)
+#endif // !defined(ASIO_NO_DEPRECATED)
 
     io_context::executor_type ex = handle1.get_executor();
     (void)ex;
diff --git a/asio/src/tests/unit/windows/random_access_handle.cpp b/asio/src/tests/unit/windows/random_access_handle.cpp
index fbd88209..c84c9d63 100644
--- a/asio/src/tests/unit/windows/random_access_handle.cpp
+++ b/asio/src/tests/unit/windows/random_access_handle.cpp
@@ -75,7 +75,7 @@ void test()
 #if !defined(ASIO_NO_DEPRECATED)
     io_context& ioc_ref = handle1.get_io_context();
     (void)ioc_ref;
-#endif !defined(ASIO_NO_DEPRECATED)
+#endif // !defined(ASIO_NO_DEPRECATED)
 
     io_context::executor_type ex = handle1.get_executor();
     (void)ex;
diff --git a/asio/src/tests/unit/windows/stream_handle.cpp b/asio/src/tests/unit/windows/stream_handle.cpp
index 499ed354..39af564a 100644
--- a/asio/src/tests/unit/windows/stream_handle.cpp
+++ b/asio/src/tests/unit/windows/stream_handle.cpp
@@ -74,7 +74,7 @@ void test()
 #if !defined(ASIO_NO_DEPRECATED)
     io_context& ioc_ref = handle1.get_io_context();
     (void)ioc_ref;
-#endif !defined(ASIO_NO_DEPRECATED)
+#endif // !defined(ASIO_NO_DEPRECATED)
 
     io_context::executor_type ex = handle1.get_executor();
     (void)ex;