Attempting to modify a function result

["Raymond C. Rawa" <Raymond.C.Rawa@nospam.boeing.com>]

I've encountered a "feature" of Ada83 or the VADS compiler that I don't
understand.

I discovered this little feature while unit testing a package that
contained a typo.

   package Foo is

      Display_Type is record
         a : integer;
         b : float;
      end record;

      function Display return Display_Type;

      procedure Huh;

   end Foo;

   package body Foo is

      The_Display : Display_Type; 
      --% internal object

      function Display return Display_Type is
      begin
         return The_Display;
      end Display;

      procedure Huh is
      begin
         Display.a := 5; -- I mean't to type: The_Display.a := 5;
      end Huh;
   end Foo;

The procedure Foo.Huh compiles and executes without error.  As a side
note, The_Display is unchanged by this procedure.

Can someone please explain what's going on here?