Re: New GNAT ports (was Re: Ada and Automotive Industry)

[ok@goanna.cs.rmit.edu.au (Richard A. O'Keefe)]

I have recently been arguing that an Ada-8501 would be doable.

Karl Cooper <"X0723$"@mailgw.sanders.lockheed.com> writes:
>We are deeply involved in a commercial product which depends heavily
>on an 8051 derivative.  Over ten thousand lines of C code are being
>maintained at the heart of this product.  Reliability and maintain-
>ability issues have been raised.  Migrating the software to GNAT-
>for-the-8051 might be a wise move for us.  Keep the group posted
>as to progress.

I do hope I haven't misled anyone.
"wistful thoughts about a product" doesn't mean "concrete plans".
I *do* think it is doable.
I *would* be interested in doing it.
However, it's not the thing that I could reasonably do on my own in
my spare time.  There *are* some students talking to me about doing
a compiler project, but their previous experience consists of having
read the Dragon book.  (That's _good_ experience, but not enough, I
think.)

I've poked around in the GNAT sources from time to time, but have never
studied the whole thing.  People who _have_ studied it:  how long do you
think it would take to understand the GNAT front end well enough to
make an informed judgement about the difficulty of writing a non-GCC
back end for it?

As I see it, the main problems in a project to actually _do_ this include
 - making an informed judgement about whether the thing is possible
   in principle [done]
 - making an informed judgement about whether doing it by writing a new
   back end for GNAT (and adding some more Restrictions) [doable with
   present resources, save possibly time]
 - finishing the design of the pragmas, System additions, and machine
   code form.
 - producing some sample programs in Ada-8051 to arouse even more interest
   (say translating everything in the book I mentioned before) [a tiny bit
   done]
 - putting together a plan (even if it's people donating time,
   like the Linux project, how _many_ people? doing what exactly?)
 - getting together a group of volunteers 
 - making the necessary changes to the front end
 - building a back end (possibly adapting one from a free C-8051 to
   start with)
 - integrating and testing, which needs a preceding step of
 - producing test programs (new code + hand translated "real" code)
 ...

In the mean time, there's a statistics language which needs a compiler,
and I think that _is_ within the capabilities of the students and myself,
so unless someone offers me startup finance to do Ada-8051, I'd be doing
the other instead.

I guess that's the point:  the only barrier to Ada-8051 is _money_,
not technical issues.
-- 
My tertiary education cost a quarter of a million in lost income
(assuming close-to-minimum wage); why make students pay even more?
Richard A. O'Keefe; http://www.cs.rmit.edu.au/%7Eok; RMIT Comp.Sci.