diff --git a/src/dbus/qdbusmetatype.cpp b/src/dbus/qdbusmetatype.cpp
index 0a0139aaed..5fe5a60a3a 100644
--- a/src/dbus/qdbusmetatype.cpp
+++ b/src/dbus/qdbusmetatype.cpp
@@ -53,14 +53,14 @@ void QDBusMetaTypeId::init()
     // reentrancy is not a problem since everything else is locked on their own
     // set the guard variable at the end
     if (!initialized.loadRelaxed()) {
-        // register our types with Qt Core (calling qMetaTypeId<T>() does this implicitly)
-        (void)message();
-        (void)argument();
-        (void)variant();
-        (void)objectpath();
-        (void)signature();
-        (void)error();
-        (void)unixfd();
+        // register our types with Qt Core
+        message().registerType();
+        argument().registerType();
+        variant().registerType();
+        objectpath().registerType();
+        signature().registerType();
+        error().registerType();
+        unixfd().registerType();
 
 #ifndef QDBUS_NO_SPECIALTYPES
         // and register Qt Core's with us
@@ -78,7 +78,6 @@ void QDBusMetaTypeId::init()
         qDBusRegisterMetaType<QVariantList>();
         qDBusRegisterMetaType<QVariantMap>();
         qDBusRegisterMetaType<QVariantHash>();
-        qDBusRegisterMetaType<QDBusObjectPath>();
 
         qDBusRegisterMetaType<QList<bool> >();
         qDBusRegisterMetaType<QList<short> >();
@@ -88,6 +87,9 @@ void QDBusMetaTypeId::init()
         qDBusRegisterMetaType<QList<qlonglong> >();
         qDBusRegisterMetaType<QList<qulonglong> >();
         qDBusRegisterMetaType<QList<double> >();
+
+        // plus lists of our own types
+        qDBusRegisterMetaType<QList<QDBusVariant> >();
         qDBusRegisterMetaType<QList<QDBusObjectPath> >();
         qDBusRegisterMetaType<QList<QDBusSignature> >();
         qDBusRegisterMetaType<QList<QDBusUnixFileDescriptor> >();
diff --git a/src/tools/qdbuscpp2xml/qdbuscpp2xml.cpp b/src/tools/qdbuscpp2xml/qdbuscpp2xml.cpp
index 295a60c01a..7182e923f3 100644
--- a/src/tools/qdbuscpp2xml/qdbuscpp2xml.cpp
+++ b/src/tools/qdbuscpp2xml/qdbuscpp2xml.cpp
@@ -433,12 +433,20 @@ int main(int argc, char **argv)
 
     QList<ClassDef> classes;
 
+    if (args.isEmpty())
+        args << u"-"_s;
     for (const auto &arg: std::as_const(args)) {
-        if (arg.startsWith(u'-'))
+        if (arg.startsWith(u'-') && arg.size() > 1)
             continue;
 
-        QFile f(arg);
-        if (!f.open(QIODevice::ReadOnly|QIODevice::Text)) {
+        QFile f;
+        if (arg == u'-') {
+            f.open(stdin, QIODevice::ReadOnly | QIODevice::Text);
+        } else {
+            f.setFileName(arg);
+            f.open(QIODevice::ReadOnly | QIODevice::Text);
+        }
+        if (!f.isOpen()) {
             fprintf(stderr, PROGRAMNAME ": could not open '%s': %s\n",
                     qPrintable(arg), qPrintable(f.errorString()));
             return 1;
diff --git a/tests/auto/tools/qdbuscpp2xml/CMakeLists.txt b/tests/auto/tools/qdbuscpp2xml/CMakeLists.txt
index 557cf57537..ef35bcd34d 100644
--- a/tests/auto/tools/qdbuscpp2xml/CMakeLists.txt
+++ b/tests/auto/tools/qdbuscpp2xml/CMakeLists.txt
@@ -16,7 +16,7 @@ qt_internal_add_test(tst_qdbuscpp2xml
         test1.h
         tst_qdbuscpp2xml.cpp
     LIBRARIES
-        Qt::DBus
+        Qt::DBusPrivate
 )
 
 # Resources:
diff --git a/tests/auto/tools/qdbuscpp2xml/tst_qdbuscpp2xml.cpp b/tests/auto/tools/qdbuscpp2xml/tst_qdbuscpp2xml.cpp
index 7282ff85b0..973c3587d2 100644
--- a/tests/auto/tools/qdbuscpp2xml/tst_qdbuscpp2xml.cpp
+++ b/tests/auto/tools/qdbuscpp2xml/tst_qdbuscpp2xml.cpp
@@ -5,9 +5,11 @@
 #include <QLibraryInfo>
 #include <QProcess>
 
+#include <QtDBus/QDBusConnection>
+#include <QtDBus/private/dbus_minimal_p.h>
+
 #include "test1.h"
 
-#include <QtDBus/QDBusConnection>
 
 // in qdbusxmlgenerator.cpp
 QT_BEGIN_NAMESPACE
@@ -32,6 +34,8 @@ class tst_qdbuscpp2xml : public QObject
 private slots:
     void qdbuscpp2xml_data();
     void qdbuscpp2xml();
+    void qtdbusTypes_data();
+    void qtdbusTypes();
 
     void initTestCase();
     void cleanupTestCase();
@@ -138,6 +142,77 @@ void tst_qdbuscpp2xml::qdbuscpp2xml()
     QCOMPARE(out, expected);
 }
 
+void tst_qdbuscpp2xml::qtdbusTypes_data()
+{
+    QTest::addColumn<QByteArray>("type");
+    QTest::addColumn<QByteArray>("expectedSignature");
+    auto addRow = [](QByteArray type, QByteArray signature) {
+        QTest::addRow("%s", type.constData()) << type << signature;
+
+        // lists and vectors
+        QTest::addRow("QList-%s", type.constData())
+                << "QList<" + type + '>' << DBUS_TYPE_ARRAY + signature;
+        QTest::addRow("QVector-%s", type.constData())
+                << "QVector<" + type + '>' << DBUS_TYPE_ARRAY + signature;
+    };
+    addRow("QDBusVariant", DBUS_TYPE_VARIANT_AS_STRING);
+    addRow("QDBusObjectPath", DBUS_TYPE_OBJECT_PATH_AS_STRING);
+    addRow("QDBusSignature", DBUS_TYPE_SIGNATURE_AS_STRING);
+    addRow("QDBusUnixFileDescriptor", DBUS_TYPE_UNIX_FD_AS_STRING);
+
+    // QDBusMessage is not a type, but must be recognized
+    QTest::newRow("QDBusMessage") << QByteArray("QDBusMessage") << QByteArray();
+}
+
+void tst_qdbuscpp2xml::qtdbusTypes()
+{
+    static const char cppSkeleton[] = R"(
+class QDBusVariantBugRepro : public QDBusAbstractAdaptor
+{
+   Q_OBJECT
+   Q_CLASSINFO("D-Bus Interface", "org.qtproject.test")
+public Q_SLOTS:
+   void method(const @TYPE@ &);
+};)";
+    static const char methodXml[] = R"(<method name="method")";
+    static const char expectedSkeleton[] = R"(<arg type="@S@" direction="in"/>)";
+
+    QFETCH(QByteArray, type);
+    QFETCH(QByteArray, expectedSignature);
+
+    const QString binpath = QLibraryInfo::path(QLibraryInfo::BinariesPath);
+    const QString command = binpath + QLatin1String("/qdbuscpp2xml");
+    QProcess process;
+    process.start(command);
+
+    process.write(QByteArray(cppSkeleton).replace("@TYPE@", type));
+    process.closeWriteChannel();
+
+    if (!process.waitForStarted()) {
+        const QString path = QString::fromLocal8Bit(qgetenv("PATH"));
+        QString message = QString::fromLatin1("'%1' could not be found when run from '%2'. Path: '%3' ").
+                          arg(command, QDir::currentPath(), path);
+        QFAIL(qPrintable(message));
+    }
+    QVERIFY2(process.waitForFinished(), qPrintable(process.errorString()));
+
+    // verify nothing was printed on stderr
+    QCOMPARE(process.readAllStandardError(), QString());
+
+    // we don't do a full XML parsing here...
+    QByteArray output = process.readAll().simplified();
+    QVERIFY2(output.contains("<node>") && output.contains("</node>"), "Output was: " + output);
+    output = output.mid(output.indexOf("<node>") + strlen("<node>"));
+    output = output.left(output.indexOf("</node>"));
+
+    QVERIFY2(output.contains(methodXml), "Output was: " + output);
+
+    if (!expectedSignature.isEmpty()) {
+        QByteArray expected = QByteArray(expectedSkeleton).replace("@S@", expectedSignature);
+        QVERIFY2(output.contains(expected), "Expected: '" + expected + "'; got: '" + output + '\'');
+    }
+}
+
 QTEST_APPLESS_MAIN(tst_qdbuscpp2xml)
 
 #include "tst_qdbuscpp2xml.moc"