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From: Jacob Sparre Andersen <jacob@jacob-sparre.dk>
Newsgroups: comp.lang.ada
Subject: Re: Why are Ada compilers difficult to write ?
Date: Wed, 20 Jun 2018 00:01:01 +0200
Organization: JSA Research & Innovation
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Xref: reader02.eternal-september.org comp.lang.ada:53175
Date: 2018-06-20T00:01:01+02:00
List-Id: <comp.lang.ada>

Vincent <vincent.diemunsch@gmail.com> writes:

> I have often heard that Ada compilers where expensive because they are
> very difficult to write, compared to Pascal or C ones. So my question
> is : what in the Ada language poses problem to a compiler ? What are
> the challenges ? Where can I find documentation about that ?

Supposedly (I have never written an Ada compiler), one of the hard parts
is to get overload resolution correct.

I can imagine that handling of accessibility of anonymous access types
(3.10.2?) can be a challenge as well.

There is also some work in handling explicitly specified record layouts
correctly, but I don't think it can be much worse than a special case of
packed records.

And finally, I suspect the fact that there is an actual validation test
suite makes it hard to get away with claiming that something is an Ada
compiler, if it doesn't implement the whole language.

Greetings,

Jacob
-- 
"Three can keep a secret if two of them are dead."