diff --git a/src/plugins/coreplugin/progressmanager/progressmanager_win.cpp b/src/plugins/coreplugin/progressmanager/progressmanager_win.cpp
index be858eb3945..05a36d88fa0 100644
--- a/src/plugins/coreplugin/progressmanager/progressmanager_win.cpp
+++ b/src/plugins/coreplugin/progressmanager/progressmanager_win.cpp
@@ -59,7 +59,9 @@ namespace {
 
 #if QT_VERSION >= 0x050000
 
+QT_BEGIN_NAMESPACE
 Q_GUI_EXPORT HICON qt_pixmapToWinHICON(const QPixmap &p);
+QT_END_NAMESPACE
 
 static inline QWindow *windowOfWidget(const QWidget *widget)
 {