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Newsgroups: comp.lang.ada
Date: Sun, 12 Feb 2023 23:22:10 -0800 (PST)
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Subject: Re: pragmas in doubly linked lists
From: Emmanuel Briot <briot.emmanuel@gmail.com>
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I believe the GNAT run time is still built without checks on.  So it is quite possible that you have kept around cursors which
are no longer valid (those cursors are direct access types in practice), and GNAT has no way to test that.
In general, it is very dangerous to keep cursors outside of a very local context where you know exactly what is going on.

You could use vectors, instead of lists, and keep the corresponding index around (rather than a cursor directly) for instance.
But I would try and refactor the code to avoid having a container with cursors into another container, that seems fragile.