Extra sausage for win math

Author: Cryoris

test/c/test_pbc.c

@@ -12,10 +12,14 @@
 
 #include "common.h"
 #include <complex.h>
-#include <math.h>
 #include <qiskit.h>
 #include <string.h>
 
+#ifdef _MSC_VER
+#define _USE_MATH_DEFINES
+#endif
+#include <math.h> // for M_PI and friends
+
 /**
  * Test gate counts after Litinski transformation.
  */