--- C:/SDK/sources/qt5/qtbase/src/corelib/kernel/qmath.h.orig	Sun Sep 23 19:17:45 2012
+++ C:/SDK/sources/qt5/qtbase/src/corelib/kernel/qmath.h	Sun Oct 14 17:51:43 2012
@@ -196,6 +196,10 @@
 #define M_PI (3.14159265358979323846)
 #endif
 
+#ifndef M_PI_2
+#define M_PI_2	(1.57079632679489661923)	/* pi/2 */
+#endif
+
 inline qreal qFastSin(qreal x)
 {
     int si = int(x * (0.5 * QT_SINE_TABLE_SIZE / M_PI)); // Would be more accurate with qRound, but slower.