diff --git a/src/corelib/kernel/qobject.h b/src/corelib/kernel/qobject.h
index 49435b97016..182edaf7f2c 100644
--- a/src/corelib/kernel/qobject.h
+++ b/src/corelib/kernel/qobject.h
@@ -207,6 +207,7 @@ public:
                             "Return type of the slot is not compatible with the return type of the signal.");
         } else {
             constexpr int FunctorArgumentCount = QtPrivate::ComputeFunctorArgumentCount<std::decay_t<Func2>, typename SignalType::Arguments>::Value;
+            [[maybe_unused]]
             constexpr int SlotArgumentCount = (FunctorArgumentCount >= 0) ? FunctorArgumentCount : 0;
             typedef typename QtPrivate::FunctorReturnType<std::decay_t<Func2>, typename QtPrivate::List_Left<typename SignalType::Arguments, SlotArgumentCount>::Value>::Value SlotReturnType;
 
diff --git a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
index 73b77932ce4..31345cc3333 100644
--- a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
+++ b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
@@ -6075,6 +6075,7 @@ void tst_QObject::connectFunctorArgDifference()
 
     connect(&timer, &QTimer::timeout, [=](){});
     connect(&timer, &QTimer::objectNameChanged, [=](const QString &){});
+    connect(&timer, &QTimer::objectNameChanged, this, [](){});
     connect(qApp, &QCoreApplication::aboutToQuit, [=](){});
 
     connect(&timer, &QTimer::objectNameChanged, [=](){});