diff --git a/include/ph7int.h b/include/ph7int.h
index 9b97fef..c91e019 100644
--- a/include/ph7int.h
+++ b/include/ph7int.h
@@ -1641,6 +1641,7 @@ PH7_PRIVATE sxi32 PH7_MemObjLoad(ph7_value *pSrc, ph7_value *pDest);
 PH7_PRIVATE sxi32 PH7_MemObjRelease(ph7_value *pObj);
 PH7_PRIVATE sxi32 PH7_MemObjToNumeric(ph7_value *pObj);
 PH7_PRIVATE ProcMemObjCast PH7_MemObjCastMethod(sxi32 iFlags);
+PH7_PRIVATE sxi32 PH7_MemObjIsNull(ph7_value *pObj);
 PH7_PRIVATE sxi32 PH7_MemObjIsNumeric(ph7_value *pObj);
 PH7_PRIVATE sxi32 PH7_MemObjIsEmpty(ph7_value *pObj);
 PH7_PRIVATE sxi32 PH7_MemObjToHashmap(ph7_value *pObj);