From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,31b0987544f45da7,start
X-Google-Attributes: gid103376,public
From: tmoran@bix.com
Subject: inheritance and private overiding
Date: 2000/05/04
Message-ID: <C2aQ4.97$ml.60170@news.pacbell.net>#1/1
X-Deja-AN: 619047050
X-Complaints-To: abuse@pacbell.net
X-Trace: news.pacbell.net 957426978 206.170.2.121 (Thu,
 04 May 2000 00:56:18 PDT)
Organization: SBC Internet Services
NNTP-Posting-Date: Thu, 04 May 2000 00:56:18 PDT
Newsgroups: comp.lang.ada
Date: 2000-05-04T00:00:00+00:00
List-Id: <comp.lang.ada>

One compiler refuses to compile this code, giving the indicated
error message.  Other compilers accept it just fine and print
"in test1" then "in test2".  Who's right?
-----------------
package test1 is
  type Root is tagged null record;
  procedure P(X : in out Root);
end test1;

with ada.text_io;
package body test1 is
  procedure P(X : in out Root) is
  begin
    ada.text_io.put_line("in test1");
  end P;
end test1;

with test1;
package test2 is
  type Branch is new test1.Root with private;
private
  type Branch is new test1.Root with null record;
  procedure P(X : in out Branch);
end test2;

with ada.text_io;
package body test2 is
  procedure P(X : in out Branch) is
  begin
    ada.text_io.put_line("in test2");
  end P;
end test2;

with test1, test2;
package test3 is
  type A is new test1.Root with null record;
  type B is new test2.Branch with null record;
end test3;

with test3;
procedure test is
  X : test3.A;
  Y : test3.B;
begin
  test3.P(X);
  test3.P(Y);   -- One compiler says "expected type A, found type B"
                -- others have no complaints
end test;