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Newsgroups: comp.lang.ada
Date: Fri, 22 Nov 2019 05:33:49 -0800 (PST)
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Subject: Re: yes another gnat bug (inherited tagged type as record field is
 too much for gnat??)
From: gerrshapovalov@gmail.com
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Xref: reader01.eternal-september.org comp.lang.ada:57588
Date: 2019-11-22T05:33:49-08:00
List-Id: <comp.lang.ada>

Just a short addition:

This is with gnat-gpl-2019 (Gentoo Linux), compiled against the 8.3.1 gcc backend.

Also, I can "cure" the compilation problem by wrapping access to the list into an (abstract and overridden in child) function returning Reference to the List.
gnat manages to compile it then. However, upon execution it throws  "discriminant check failed" run-time exception..

(Reference to the list is that standard construct like:

type Input_Reference_Type  (Data : not null access IL.List_Interface'Class) is null record
        with Implicit_Dereference => Data;

This allows to return a callable object that can be used to call methods of List and do indexed data access (assignment/reading)
)