Re: Companies Only Offering Ada-95 Compilers

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

On 2012-05-20, Nomen Nescio <nobody@dizum.com> wrote:
>
> GNAT is certainly very good. But it is a pain in the ass in many ways. It is
> GPL only and even if you use gcc Ada eventually that is going to cause
> problems as GPL moves from GPL2 to 3, and who knows what's next. LGPL
> libraries today, tomorrow everythings GPL, you trusted them, you put all
> your eggs in one basket, you got screwed.
>

I am assuming above that by "gcc Ada", you mean the FSF branch; I use the
FSF branch in order to avoid GPL issues and because when I need a RTOS, the
RTOS I use (RTEMS) also uses it.

The GPL 2 to GPL 3 comment has caught my attention. Given that the FSF Ada
runtime libraries come with the GMGPL exception, what issues are raised
by the GPL 2 to GPL 3 conversion ? I am assuming I have missed something,
but I don't know what.

On a more general note, one of the problems is that if you want to do hard
real time/bare metal/low level programming using a Wirth type language,
which I do, then Ada appears to be the only viable choice. I would really
like to find another choice as a backup option, but what I have looked at
so far (Modula-2, a Oberon variant, etc) appear to all be one-off ports
or lacking in other ways.

There are more options available if you want to do non-realtime application
level programming under a mainstream operating system, but for system level
work, Ada appears to be the only real viable option. Has anyone here used
another Wirth type language in a real time system level environment, and if
so, what kind of experience did you have ?

>
> Back to GNAT, it is often not (easily) available on many POSIX platforms and
> architectures. We have discussed Librecore's abandonment of Solaris
> recently. There is still a lot of SPARC UNIX being used and no place to get 
> a trusted build and no instructions on building yourself. I'm not even sure
> there is an Intel Solaris GNAT available anywhere. Is it really that hard
> for people who "have the technology" to make this available? Yes, we are
> willing to pay for something as good as GNAT, just not $20,000. Not for one
> person who isn't going to make any money on it. gcc Ada would be fine (until
> Stallman drops his GPL bomb on the libraries) but it's only available on
> Linux and Windows.

Can you point to this "GPL bomb" issue, please ? It's something I need to
become aware of and a quick search didn't reveal anything. BTW, wouldn't it
affect C++ code just as much as Ada code ? If that's the case, then we may
end up with a XFree86/X.Org type situation once again.

BTW, as well as the native support, FSF Ada does work as a cross compiler
for a couple of targets. I have used it in the past to run Ada code on AVR
MCUs and more recently, on ARM based MCUs using RTEMS.

Simon.

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