diff --git a/source/os/src/osMath.c b/source/os/src/osMath.c
index 5ac0fce006ae4f8b510a102d517392b98c2e88f8..067b130b575f4a702d16373060627ee69583fcef 100644
--- a/source/os/src/osMath.c
+++ b/source/os/src/osMath.c
@@ -16,6 +16,7 @@
 #define ALLOW_FORBID_FUNC
 #define _DEFAULT_SOURCE
 #include <stdlib.h>
+#include "osDef.h"
 
 #ifdef WINDOWS
 void swapStr(char* j, char* J, int width) {