diff --git a/src/hb.hh b/src/hb.hh
index 778cb6992..01618ec87 100644
--- a/src/hb.hh
+++ b/src/hb.hh
@@ -475,7 +475,9 @@ static_assert ((sizeof (hb_var_int_t) == 4), "");
 
 
 /* Size signifying variable-sized array */
-#define HB_VAR_ARRAY 1
+#ifndef HB_VAR_ARRAY
+#define HB_VAR_ARRAY 0
+#endif
 
 static inline double
 _hb_roundf (float x)