diff --git a/enumerator.c b/enumerator.c
index a366b75232..24444cdc53 100644
--- a/enumerator.c
+++ b/enumerator.c
@@ -550,6 +550,8 @@ enumerator_each(int argc, VALUE *argv, VALUE obj)
 	    args = rb_ary_new4(argc, argv);
 	}
 	e->args = args;
+	e->size = Qnil;
+	e->size_fn = 0;
     }
     if (!rb_block_given_p()) return obj;
     return enumerator_block_call(obj, 0, obj);
diff --git a/test/ruby/test_enumerator.rb b/test/ruby/test_enumerator.rb
index a24ff00d96..0839c2c3dd 100644
--- a/test/ruby/test_enumerator.rb
+++ b/test/ruby/test_enumerator.rb
@@ -301,8 +301,11 @@ class TestEnumerator < Test::Unit::TestCase
       yield
     end
     ary = []
-    e = o.to_enum.each(ary)
-    e.next
+    e = o.to_enum { 1 }
+    assert_equal(1, e.size)
+    e_arg = e.each(ary)
+    assert_equal(nil, e_arg.size)
+    e_arg.next
     assert_equal([1], ary)
   end