diff --git a/include/sdbusplus/asio/detail/async_send_handler.hpp b/include/sdbusplus/asio/detail/async_send_handler.hpp
index 5d33b2a..9cb7978 100644
--- a/include/sdbusplus/asio/detail/async_send_handler.hpp
+++ b/include/sdbusplus/asio/detail/async_send_handler.hpp
@@ -76,8 +76,9 @@
     {
         using unpack_t = unpack_userdata<CompletionToken>;
         auto context = std::make_unique<unpack_t>(std::move(token));
-        int ec = sd_bus_call_async(bus, NULL, mesg.get(), &unpack_t::do_unpack,
-                                   context.get(), timeout);
+        int ec =
+            sd_bus_call_async(bus, nullptr, mesg.get(), &unpack_t::do_unpack,
+                              context.get(), timeout);
         if (ec < 0)
         {
             auto err =
diff --git a/include/sdbusplus/utility/container_traits.hpp b/include/sdbusplus/utility/container_traits.hpp
index 190252b..5d14603 100644
--- a/include/sdbusplus/utility/container_traits.hpp
+++ b/include/sdbusplus/utility/container_traits.hpp
@@ -29,7 +29,7 @@
     static constexpr no test(...);
 
   public:
-    static constexpr bool value = sizeof(test<T>(0)) == sizeof(yes);
+    static constexpr bool value = sizeof(test<T>(nullptr)) == sizeof(yes);
 };
 
 template <typename T>