[Info-vax] The future of Ada on VMS

[Simon Clubley]

On 2018-05-21, Arne Vajhøj <arne at vajhoej.dk> wrote:
> On 5/21/2018 1:38 PM, Dave Froble wrote:
>> But once again, you're predicting without any idea of what might happen. 
>>   You say there will not be an Ada compiler.  How do you know that? 
>> Perhaps there is not one now, or any announced plans for one.  But VSI 
>> will look at what their customers are asking for, and if there is demand 
>> and good business sense to do so, do you doubt John's ability to produce 
>> a new up to date Ada compiler?
>
> Ada is a bit more uncertain.
>

Try a lot more uncertain (unfortunately).

> My understanding is that VSI has not talked about migrating
> the extremely old DEC Ada 83 but has talked about getting ACT
> to port their modern Ada. But ACT has dropped VMS as a platform,
>

This is my understanding as well.

When DEC/CPQ/HP management decided to go with an external vendor
for Ada instead of building an Ada 95 compiler in-house, that was
when they lost control of the long term Ada ecosystem and became
dependent on that external vendor's plans.

> I do not doubt that John could create an Ada compiler, but
> every indication is that he will be working on other stuff.
>

Creating an Ada compiler from scratch is a massive job. A number
of people (who know way more about what is involved than I do)
have looked at this possibility in various forms and have come
to the same conclusion.

> So it will be VSI management talking to ACT management.
>
> Or talk to the great guys that made GNAT work on VMS I64
> about an x86-64 version. See post some time ago!
>

That's not really a meaningful comparison unfortunately.

The code for Itanium already existed in the code base he used and
it was mostly a matter of learning how to use an existing GNAT Pro
compiler for Alpha VMS to build an Itanium compiler.

All the necessary bits for x86-64 on VMS would need to be added
to the code base before such an attempt could be made for x86-64.

This would mean however that VSI would be maintaining GCC for
Ada only and maintaining LLVM for all the other compilers.

> If I were dependent on Ada on VMS, then I would also be
> a bit concerned.
>

Very much agreed.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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