Re: Ada on openvms for alpha

[Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>]

On 2014-10-26, Brian Drummond <brian3@shapes.demon.co.uk> wrote:
> On Sat, 25 Oct 2014 12:29:00 +0100, Simon Wright wrote:
>
>> Luke A. Guest <laguest@archeia.com> writes:
>> 
>>> David Botton <david@botton.com> wrote:
>>>
>>>> For example, I don't have the interest nor am I the expert, but some
>>>> one that wanted to a make a few dollars should be able to roll this
>>>> guy an openVMS alpha of at least an older version of GNAT that will
>>>> work. I am sure he would be will to pay for it.
>>>> 
>>>> 
>>> Don't quote me on this but I'm fairly sure the VMS packages are not in
>>> the FSF tree.
>> 
>> GCC 4.9.1 has 58 files with *vms* in the name in gcc/ada. For example,
>> mlib-tgt-specific-vms-alpha.adb, mlib-tgt-specific-vms-ia64.adb
>
> And the alpha backend still looks to be there in gcc/config/alpha . 
> If nobody's built it in that configuration for years there's likely to be 
> some bit-rot, but it may be recoverable with a bit (probably quite a lot) 
> of work.
>

You start by building it as a cross compiler on Linux and use copies
of the VMS headers and libraries from your target system. Of the four
target languages I tried (Ada, C, C++, Fortran) these were the results
from building the cross compiler:

Ada	Internal compiler error while building the GNAT frontend
C	Test programs written in C and compiled on Linux using the
	cross compiler appear to run ok on VMS
C++	Build failure while building the cross compiler
Fortran	Test executables build and link and then fail early on
	during image activation on the target VMS system.

The C++ issue looks reasonably easy enough to fix, but I wasn't motivated
to spend any time there until the Fortran runtime failures and Ada
internal compiler error issues were fixed.

In the end however, there was more work involved than I was willing
to spend given that I have a large stack of other hobbyist projects
which are of more interest to me. :-)

Simon.

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