[Info-vax] Ada on VMS, was: Re: Making the CRTL version dependency information useful

[Simon Clubley]

On 2018-01-17, gérard Calliet <gerard.calliet at pia-sofer.fr> wrote:
>
> The new initiative is to make available for free a built of the GNAT Ada 
> compiler -as is- .
>
> The built has been made because of a port project to itanium which was 
> beginning a month after Adacore gave up any support for VMS.
>

Well at least we now know that Ada on VMS is dead which was news to me. :-(

> The only validation we could make was using it for the port. The port is 
> successfull, ans it seems it works. The application is used to control 
> the automatic line 14 of uderground in Paris.
>

Are you planning to import new functionality from the current GNAT code
base or will your compiler be frozen at its current level of functionality ?

> The business plan is very simple: anyone can use the built for free, and 
> we can propose support, determining specific perimeters with the 
> customer. The more we'll get support  contracts, the more we can make 
> evolutions on the built.
>
> We hoped we could get some help from VSI, but they think we are too 
> little (too "new", perhaps :) )to speak with them.
>

Did VSI tell you that or did they just not bother replying to your
emails ? If it's the latter, don't read too much into it as that has
apparently happened quite a bit in the past (based on comments here).

>> 
> Right. And I confirm it's no way with Adacore. Good people, got help 
> when we were rebuilding, but they do confirm the VMS story is finally 
> closed for them.
>

That in itself is useful information. Thanks.

> I'm not sure. GNAT Ada is gcc and VSI VMS will be llvm.
> The port we have done begins cross-compiling a gcc, it'll be a total 
> different thing using llvm.

Yes, it will probably be closer to the situation I found myself in with
my failed efforts trying to build the GNAT cross compiler on Linux (you
had the advantage of being able to start with a GNAT Pro compiler which
was not an option available to me.)

> Adacore is studying now a transfer to llvm, but it is not for now, and 
> not for VMS.
> [[we are on gcc 4.7, because newer version use c++ and last year no way 
> using c++ for a VMS port]]
>

That C++ requirement is a major problem for VMS. One advantage of
building cross compilers on Linux is that you can just use the
modern C++ compilers on Linux as part of the cross compiler build.

LLVM is even worse because they keep changing the LLVM source code to
use the latest C++ features.

I wish someone would make a nice portable lightweight compiler generator
toolchain with a good range of backend targets and wasn't full of bloat.

Simon.

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