[numerics] add M_PI definition if not founf in math.h
#include <float.h>
#include <stdlib.h>
+#ifndef M_PI
+#define M_PI 3.14159265358979323846264338327950288 /* pi */
+#define M_PI_2 1.57079632679489661923132169163975144 /* pi/2 */
+#endif
+
#include "numerics_verbose.h"
#include "SiconosCompat.h"
