diff --git a/src/dbus/qdbusargument.cpp b/src/dbus/qdbusargument.cpp
index 6704ba5812..99e60244da 100644
--- a/src/dbus/qdbusargument.cpp
+++ b/src/dbus/qdbusargument.cpp
@@ -71,7 +71,7 @@ bool QDBusArgumentPrivate::checkWrite(QDBusArgumentPrivate *&d)
 {
     if (!d)
         return false;
-    if (d->direction == Marshalling) {
+    if (d->direction == Direction::Marshalling) {
         if (!d->marshaller()->ok)
             return false;
 
@@ -99,7 +99,7 @@ bool QDBusArgumentPrivate::checkRead(QDBusArgumentPrivate *d)
 {
     if (!d)
         return false;
-    if (d->direction == Demarshalling)
+    if (d->direction == Direction::Demarshalling)
         return true;
 
 #ifdef QT_DEBUG
@@ -537,7 +537,7 @@ QString QDBusArgument::currentSignature() const
 {
     if (!d)
         return QString();
-    if (d->direction == QDBusArgumentPrivate::Demarshalling)
+    if (d->direction == QDBusArgumentPrivate::Direction::Demarshalling)
         return d->demarshaller()->currentSignature();
     else
         return d->marshaller()->currentSignature();
@@ -556,7 +556,7 @@ QDBusArgument::ElementType QDBusArgument::currentType() const
 {
     if (!d)
         return UnknownType;
-    if (d->direction == QDBusArgumentPrivate::Demarshalling)
+    if (d->direction == QDBusArgumentPrivate::Direction::Demarshalling)
         return d->demarshaller()->currentType();
     return UnknownType;
 }
diff --git a/src/dbus/qdbusargument_p.h b/src/dbus/qdbusargument_p.h
index 79e2283c1c..0c7641247f 100644
--- a/src/dbus/qdbusargument_p.h
+++ b/src/dbus/qdbusargument_p.h
@@ -35,8 +35,11 @@ class QDBusDemarshaller;
 class QDBusArgumentPrivate
 {
 public:
-    explicit QDBusArgumentPrivate(QDBusConnection::ConnectionCapabilities flags = {})
-        : capabilities(flags)
+    enum class Direction { Marshalling, Demarshalling };
+
+    explicit QDBusArgumentPrivate(Direction direction,
+                                  QDBusConnection::ConnectionCapabilities flags = {})
+        : capabilities(flags), direction(direction)
     {
     }
     virtual ~QDBusArgumentPrivate();
@@ -60,19 +63,15 @@ public:
     DBusMessage *message = nullptr;
     QAtomicInt ref = 1;
     QDBusConnection::ConnectionCapabilities capabilities;
-    enum Direction {
-        Marshalling,
-        Demarshalling
-    } direction;
+    Direction direction;
 };
 
 class QDBusMarshaller: public QDBusArgumentPrivate
 {
 public:
     explicit QDBusMarshaller(QDBusConnection::ConnectionCapabilities flags = {})
-        : QDBusArgumentPrivate(flags)
+        : QDBusArgumentPrivate(Direction::Marshalling, flags)
     {
-        direction = Marshalling;
     }
     ~QDBusMarshaller();
 
@@ -130,9 +129,8 @@ class QDBusDemarshaller: public QDBusArgumentPrivate
 {
 public:
     explicit QDBusDemarshaller(QDBusConnection::ConnectionCapabilities flags = {})
-        : QDBusArgumentPrivate(flags)
+        : QDBusArgumentPrivate(Direction::Demarshalling, flags)
     {
-        direction = Demarshalling;
     }
     ~QDBusDemarshaller();
 
diff --git a/src/dbus/qdbusmarshaller.cpp b/src/dbus/qdbusmarshaller.cpp
index 0320bdb62c..b2ed2586fb 100644
--- a/src/dbus/qdbusmarshaller.cpp
+++ b/src/dbus/qdbusmarshaller.cpp
@@ -360,7 +360,7 @@ bool QDBusMarshaller::appendVariantInternal(const QVariant &arg)
         QDBusDemarshaller demarshaller(capabilities);
         demarshaller.message = q_dbus_message_ref(d->message);
 
-        if (d->direction == Demarshalling) {
+        if (d->direction == Direction::Demarshalling) {
             // it's demarshalling; just copy
             demarshaller.iterator = static_cast<QDBusDemarshaller *>(d)->iterator;
         } else {