Strange error message

[Charly <carl.weierstrass@googlemail.com>]

Hi,

when I defined a class hierarchy I encountered a problem, that I could reduce 
to the following few lines:

This version compiles without problems:
-----------------
package Test is

   type Base is tagged private;
   function Create return Base;

   type High is new Base with private;

private

   type Base is tagged null record;

   type High is new Base with null record;

end Test;
-----------------

but this one

-----------------
package Test is

   type Base is tagged private;
   function Create return Base;

   type High is new Base with private;

private

   type Base is tagged null record;

   type High is new Base with record     --
      H_Val : Natural := 0;              -- these lines are changed
   end record;                           --

end Test;
-----------------

does not compile an I get an error:

   type must be declared abstract or "Create" overridden

Why do I have to overide the function Create for type High.
I don't see the necessity.

Btw. I'm using GNAT GPL 2014 but the same happens with 2013 version.

Charly