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From: Maciej Sobczak <see.my.homepage@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: How to return an empty aggregate
Date: Wed, 2 Apr 2008 00:16:40 -0700 (PDT)
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On 1 Kwi, 19:18, Adam Beneschan <a...@irvine.com> wrote:

> As far as I can tell, what Maciej is trying to do is perfectly fine,
> there aren't any language corners that would cause a problem, and the
> compiler is misbehaving.

Looks like this is related to my previous bug report. The smallest
test case I've found is:

procedure A is

   type Base_1 is interface;
   type Base_2 is interface;
   type Middle is Interface and Base_1 and Base_2;

   type Derived is new Middle with null record;

   function Make_Derived return Derived is
   begin
      return Derived' (others => <>);
   end Make_Derived;

   D : Base_1'Class := Make_Derived;

begin
   null;
end;

This compiles and runs fine.
After changing the order of progenitors in the definition of Middle
(or changing the type of D to Base_2'Class) the program still
compiles, but fails with segfault at runtime - this, however, takes a
couple of seconds.

Time for another entry in bugzilla.

--
Maciej Sobczak * www.msobczak.com * www.inspirel.com