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From: "Anh Vo" <anhvofrcaus@gmail.com>
Newsgroups: comp.lang.ada
Subject: Not null feature with anonymous and named access types
Date: 12 Jun 2006 13:33:16 -0700
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Date: 2006-06-12T13:33:16-07:00
List-Id: <comp.lang.ada>

I have been exploring the not null feature with anonymous access type
and named access type. One thing have learned that an access variable
declared based on these types will raise a Constraint_Error when
deallocating this access variable as shown in the code below.

Access_Type:
declare
   type Access_Integer is not null access all Integer;
   procedure Free is new Unchecked_Deallocation (Integer,
Access_Integer);
   My_Ref_1 : Access_Integer := new Integer' (111);
   My_Ref_2 : not null access Integer := new Integer' (222);
begin
   -- perform action on My_Ref_1 and My_Ref_2
   Free (My_Ref_1);  -- raising Constraint_Error under GNAT/gcc-4.2.0
   Free (Access_Integer (My_Ref_2)); -- did too
end Access_Type;

Does this behavior reflect ARM 2005 requirements?
Thanks in advance for your comments.

AV