3 files changed, 22 insertions, 20 deletions
diff --git a/src/corelib/kernel/qmetaobject.cpp b/src/corelib/kernel/qmetaobject.cpp
index 83f670d9a50..e2e3c9b8083 100644
--- a/src/corelib/kernel/qmetaobject.cpp
+++ b/src/corelib/kernel/qmetaobject.cpp
@@ -646,10 +646,11 @@ bool QMetaObjectPrivate::methodMatch(const QMetaObject *m, const QMetaMethod &me
     int paramsIndex = data.parameters() + 1;
     for (int i = 0; i < argc; ++i) {
         uint typeInfo = m->d.data[paramsIndex + i];
-        if (int id = types[i].type()) {
-            if (id == QMetaType(ifaces[i]).id())
+        QMetaType mt = types[i].metaType();
+        if (mt.isValid()) {
+            if (mt == QMetaType(ifaces[i]))
                 continue;
-            if (id != typeFromTypeInfo(m, typeInfo))
+            if (mt.id() != typeFromTypeInfo(m, typeInfo))
                 return false;
         } else {
             if (types[i].name() == QMetaType(ifaces[i]).name())
@@ -3994,7 +3995,7 @@ int QMetaProperty::notifySignalIndex() const
     if (idx >= 0)
         return idx + m->methodOffset();
     // try 1-arg signal
-    QArgumentType argType(typeId());
+    QArgumentType argType(metaType());
     idx = QMetaObjectPrivate::indexOfMethodRelative<MethodSignal>(&m, signalName, 1, &argType);
     if (idx >= 0)
         return idx + m->methodOffset();
diff --git a/src/corelib/kernel/qmetaobject_p.h b/src/corelib/kernel/qmetaobject_p.h
index c2b716ac52d..1c59a57cce4 100644
--- a/src/corelib/kernel/qmetaobject_p.h
+++ b/src/corelib/kernel/qmetaobject_p.h
@@ -41,21 +41,19 @@ Q_CORE_EXPORT int qMetaTypeTypeInternal(const char *);
 class QArgumentType
 {
 public:
-    QArgumentType(int type)
-        : _type(type)
+    QArgumentType() = default;
+    QArgumentType(QMetaType metaType)
+        : _metaType(metaType)
     {}
     QArgumentType(const QByteArray &name)
-        : _type(qMetaTypeTypeInternal(name.constData())), _name(name)
+        : _metaType(QMetaType(qMetaTypeTypeInternal(name.constData()))), _name(name)
     {}
-    QArgumentType()
-        : _type(0)
-    {}
-    int type() const
-    { return _type; }
-    QByteArray name() const
+    QMetaType metaType() const noexcept
+    { return _metaType; }
+    QByteArrayView name() const noexcept
     {
-        if (_type && _name.isEmpty())
-            const_cast<QArgumentType *>(this)->_name = QMetaType(_type).name();
+        if (_name.isEmpty())
+            return metaType().name();
         return _name;
     }
 
@@ -63,14 +61,14 @@ private:
     friend bool comparesEqual(const QArgumentType &lhs,
                               const QArgumentType &rhs)
     {
-        if (lhs._type && rhs._type)
-            return lhs._type == rhs._type;
+        if (lhs.metaType().isValid() && rhs.metaType().isValid())
+            return lhs.metaType() == rhs.metaType();
         else
             return lhs.name() == rhs.name();
     }
     Q_DECLARE_EQUALITY_COMPARABLE_NON_NOEXCEPT(QArgumentType)
 
-    int _type;
+    QMetaType _metaType;
     QByteArray _name;
 };
 Q_DECLARE_TYPEINFO(QArgumentType, Q_RELOCATABLE_TYPE);
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp
index 188cfd28a02..36505fae62f 100644
--- a/src/corelib/kernel/qobject.cpp
+++ b/src/corelib/kernel/qobject.cpp
@@ -101,13 +101,14 @@ static int *queuedConnectionTypes(const QMetaMethod &method)
     return typeIds;
 }
 
+// ### Future work: replace with an array of QMetaType or QtPrivate::QMetaTypeInterface *
 static int *queuedConnectionTypes(const QArgumentType *argumentTypes, int argc)
 {
     auto types = std::make_unique<int[]>(argc + 1);
     for (int i = 0; i < argc; ++i) {
         const QArgumentType &type = argumentTypes[i];
-        if (type.type())
-            types[i] = type.type();
+        if (type.metaType().isValid())
+            types[i] = type.metaType().id();
         else if (type.name().endsWith('*'))
             types[i] = QMetaType::VoidStar;
         else
@@ -3059,6 +3060,8 @@ QMetaObject::Connection QObject::connect(const QObject *sender, const char *sign
         return QMetaObject::Connection(nullptr);
     }
 
+    // ### Future work: attempt get the metatypes from the meta object first
+    // because it's possible they're all registered.
     int *types = nullptr;
     if ((type == Qt::QueuedConnection)
             && !(types = queuedConnectionTypes(signalTypes.constData(), signalTypes.size()))) {