Add empty recarray test, check for calloc fail
diff --git a/example/example20.py b/example/example20.py
index ed34548..d1bc942 100644
--- a/example/example20.py
+++ b/example/example20.py
@@ -17,3 +17,8 @@
 assert arr.dtype == dtype
 check_eq(arr, [(False, 0, 0.0), (True, 1, 1.5), (False, 2, 3.0)], dtype)
 check_eq(arr, [(False, 0, 0.0), (True, 1, 1.5), (False, 2, 3.0)], base_dtype)
+
+arr = create_rec_simple(0)
+assert arr.dtype == dtype
+check_eq(arr, [], dtype)
+check_eq(arr, [], base_dtype)