diff --git a/shared/SqMod.h b/shared/SqMod.h
index 6accee73..41b68e98 100644
--- a/shared/SqMod.h
+++ b/shared/SqMod.h
@@ -28,6 +28,8 @@
 #if !defined(_SQ_MOD_H_)
 #define _SQ_MOD_H_
 
+#include <stddef.h>
+
 #include "SqAPI.h"
 #include "vcmp.h"