diff --git a/player.c b/player.c
index 55374ad..63b6d50 100644
--- a/player.c
+++ b/player.c
@@ -12,6 +12,11 @@
 #include <stdlib.h>
 
 
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+
 static inline double dabs(double x) {
 	return x < 0.0 ? -x : x;
 }