diff --git a/src/shared/qtgradienteditor/qtgradientwidget.cpp b/src/shared/qtgradienteditor/qtgradientwidget.cpp
index 5559011548781552d322073c01aa9a13d1d8acea..2f1bda6d9535d7b54f18d70f10663dd1c12eb065 100644
--- a/src/shared/qtgradienteditor/qtgradientwidget.cpp
+++ b/src/shared/qtgradienteditor/qtgradientwidget.cpp
@@ -47,7 +47,9 @@
 #include <QtGui/QMouseEvent>
 #include <QtGui/QRegion>
 
+#ifndef _USE_MATH_DEFINES
 #define _USE_MATH_DEFINES
+#endif
 
 
 #include "math.h"