diff --git a/sources/qetapp.cpp b/sources/qetapp.cpp
index ce819c636..ff8af961a 100644
--- a/sources/qetapp.cpp
+++ b/sources/qetapp.cpp
@@ -940,7 +940,7 @@ void QETApp::invertMainWindowVisibility(QWidget *window) {
 	Autodetec Windows style
 	@param Windows style
 */
-#ifdef Q_WS_WIN
+#ifdef defined(Q_WS_WIN)
 			if ((QSysInfo::WindowsVersion >= QSysInfo::WV_VISTA
 				&& QSysInfo::WindowsVersion < QSysInfo::WV_NT_based))
 				style = QLatin1String("WindowsVista");