Renamed GLFW_NO_GLU to GLFW_INCLUDE_GLU.
diff --git a/examples/boing.c b/examples/boing.c
index 33696e4..49d602c 100644
--- a/examples/boing.c
+++ b/examples/boing.c
@@ -30,6 +30,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <math.h>
+
+#define GLFW_INCLUDE_GLU
 #include <GL/glfw3.h>