diff --git a/src/agentbase/agentbase.cpp b/src/agentbase/agentbase.cpp
--- a/src/agentbase/agentbase.cpp
+++ b/src/agentbase/agentbase.cpp
@@ -904,6 +904,7 @@
 
 void AgentBase::debugAgent(int argc, char **argv)
 {
+    Q_UNUSED(argc);
 #ifdef Q_OS_WIN
     if (qEnvironmentVariableIsSet("AKONADI_DEBUG_WAIT")) {
         if (QByteArray(argv[0]).endsWith(qgetenv("AKONADI_DEBUG_WAIT") + ".exe")) {
@@ -913,6 +914,8 @@
             DebugBreak();
         }
     }
+#else
+    Q_UNUSED(argv);
 #endif
 }
 
diff --git a/src/core/itemsync.cpp b/src/core/itemsync.cpp
--- a/src/core/itemsync.cpp
+++ b/src/core/itemsync.cpp
@@ -386,7 +386,6 @@
 
 void ItemSyncPrivate::processItems()
 {
-    Q_Q(ItemSync);
     // added / updated
     for (const Item &remoteItem : qAsConst(mCurrentBatchRemoteItems)) {
         if (remoteItem.remoteId().isEmpty()) {
diff --git a/src/core/monitor_p.h b/src/core/monitor_p.h
--- a/src/core/monitor_p.h
+++ b/src/core/monitor_p.h
@@ -400,7 +400,6 @@
     template<typename Signal, typename ... Args>
     bool emitToListeners(Signal signal, Args ... args)
     {
-        Q_Q(Monitor);
         if (hasListeners(signal)) {
             Q_EMIT (q_ptr->*signal)(std::forward<Args>(args) ...);
             return true;
diff --git a/src/core/monitor_p.cpp b/src/core/monitor_p.cpp
--- a/src/core/monitor_p.cpp
+++ b/src/core/monitor_p.cpp
@@ -175,7 +175,6 @@
 
 void MonitorPrivate::slotUpdateSubscription()
 {
-    Q_Q(Monitor);
     if (pendingModificationTimer) {
         pendingModificationTimer->stop();
         std::exchange(pendingModificationTimer, nullptr)->deleteLater();