diff --git a/src/network/socket/qsocks5socketengine.cpp b/src/network/socket/qsocks5socketengine.cpp
index 2669614f3a..a36b5d3b70 100644
--- a/src/network/socket/qsocks5socketengine.cpp
+++ b/src/network/socket/qsocks5socketengine.cpp
@@ -1447,7 +1447,7 @@ qint64 QSocks5SocketEngine::bytesAvailable() const
 #ifndef QT_NO_UDPSOCKET
     else if (d->mode == QSocks5SocketEnginePrivate::UdpAssociateMode
              && !d->udpData->pendingDatagrams.isEmpty())
-        return d->udpData->pendingDatagrams.first().data.size();
+        return d->udpData->pendingDatagrams.constFirst().data.size();
 #endif
     return 0;
 }