diff --git a/loopy/kernel/array.py b/loopy/kernel/array.py
index 2131fe0087ded852a79c5397647b55972628efaa..6f71753ba2fcef286985ef8f8793d929164c0762 100644
--- a/loopy/kernel/array.py
+++ b/loopy/kernel/array.py
@@ -817,7 +817,7 @@ def get_access_info(ary, index, eval_expr):
     array_name = ary.name
 
     if ary.shape is None:
-        return AccessInfo(array_name=array_name, subscripts=index, vector_index=0)
+        return AccessInfo(array_name=array_name, subscripts=index, vector_index=None)
 
     if len(ary.shape) != len(index):
         raise RuntimeError("subscript to '%s[%s]' has the wrong "