diff --git a/include/wx/crt.h b/include/wx/crt.h
index ee7f6cb945..4ee5a8accd 100644
--- a/include/wx/crt.h
+++ b/include/wx/crt.h
@@ -11,6 +11,8 @@
 #ifndef _WX_CRT_H_
 #define _WX_CRT_H_
 
+#include "wx/defs.h"
+
 // include wxChar type definition:
 #include "wx/chartype.h"