diff --git a/include/GL/glu.h b/include/GL/glu.h
index 3cd1113509f..cd967ac5ed4 100644
--- a/include/GL/glu.h
+++ b/include/GL/glu.h
@@ -38,8 +38,12 @@
 #include <GL/gl.h>
 
 #ifndef GLAPIENTRY
+#if defined(_MSC_VER) || defined(__MINGW32__)
+#define GLAPIENTRY __stdcall
+#else
 #define GLAPIENTRY
 #endif
+#endif
 
 #ifndef GLAPIENTRYP
 #define GLAPIENTRYP GLAPIENTRY *