diff --git a/src/libs/qmldebug/qmldebugconnection.cpp b/src/libs/qmldebug/qmldebugconnection.cpp
index 33b050efb37..50736b6468e 100644
--- a/src/libs/qmldebug/qmldebugconnection.cpp
+++ b/src/libs/qmldebug/qmldebugconnection.cpp
@@ -346,8 +346,12 @@ void QmlDebugConnection::connectToHost(const QString &hostName, quint16 port)
         emit logStateChange(socketStateToString(state));
     });
 
-    connect(socket, QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error),
-            this, [this](QAbstractSocket::SocketError error) {
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+    const auto errorOccurred = QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error);
+#else
+    const auto errorOccurred = &QAbstractSocket::errorOccurred;
+#endif
+    connect(socket, errorOccurred, this, [this](QAbstractSocket::SocketError error) {
         emit logError(socketErrorToString(error));
         socketDisconnected();
     }, Qt::QueuedConnection);
diff --git a/src/plugins/qmakeprojectmanager/externaleditors.cpp b/src/plugins/qmakeprojectmanager/externaleditors.cpp
index 50983370c30..bbcc87e4fe9 100644
--- a/src/plugins/qmakeprojectmanager/externaleditors.cpp
+++ b/src/plugins/qmakeprojectmanager/externaleditors.cpp
@@ -288,8 +288,12 @@ bool DesignerExternalEditor::startEditor(const QString &fileName, QString *error
         m_processCache.insert(binary, socket);
         auto mapSlot = [this, binary] { processTerminated(binary); };
         connect(socket, &QAbstractSocket::disconnected, this, mapSlot);
-        connect(socket, QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error),
-                this, mapSlot);
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+        const auto errorOccurred = QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error);
+#else
+        const auto errorOccurred = &QAbstractSocket::errorOccurred;
+#endif
+        connect(socket, errorOccurred, this, mapSlot);
     }
     return true;
 }
diff --git a/src/tools/iostool/main.cpp b/src/tools/iostool/main.cpp
index 8eccc68d171..3e4141aaf3b 100644
--- a/src/tools/iostool/main.cpp
+++ b/src/tools/iostool/main.cpp
@@ -225,9 +225,12 @@ void Relayer::setClientSocket(QTcpSocket *clientSocket)
     QTC_CHECK(!m_clientSocket);
     m_clientSocket = clientSocket;
     if (m_clientSocket) {
-        connect(m_clientSocket,
-                QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error),
-                this, &Relayer::handleClientHasError);
+#if QT_VERSION < QT_VERSION_CHECK(5, 15, 0)
+        const auto errorOccurred = QOverload<QAbstractSocket::SocketError>::of(&QAbstractSocket::error);
+#else
+        const auto errorOccurred = &QAbstractSocket::errorOccurred;
+#endif
+        connect(m_clientSocket, errorOccurred, this, &Relayer::handleClientHasError);
         connect(m_clientSocket, &QAbstractSocket::disconnected,
                 this, [this](){server()->removeRelayConnection(this);});
     }