Re: Mixing Cygnus & Gnat compilers on the same machine

["Marin David Condic" <marin.condic.auntie.spam@pacemicro.com>]

Thanks for the response.

As for the business model - I think I hit that at other points. It isn't
intended as a criticism - just an observation that if the Ada part of gcc
gets more widely spread, it changes the game somewhat and it isn't obvious
that this is necessarily good for any particular players. It may very well
be, but there could be downsides to it depending on how one wanted to
structure their business strategy.

As for my apparent misconception about how Gnat would potentially move to
different platforms, let me ask this: If Gnat and gcc merge, doesn't that
mean that the Ada front end is now hooked to the normally distributed gcc
back end? I noticed on the web site for gcc
(http://www.gnu.org/software/gcc/gcc.html) that they talk about front ends
for a variety of languages and my understanding was that the various front
ends are - or could be - built together much as Gnat will translate Ada or
C. (or Cygnus will translate C or C++) Maybe it requires some additional
tinkering to get the front ends connected and operating together? I'd
anticipate that not every machine dependency would automatically get
resolved and that there would be bugs, but it seems logical that if the Ada
front end makes the same intermediate code as the C front end (or Fortran
front end or Java front end...) the common back end ought to more or less
continue to do its job.

Anyway, I wasn't expecting that some kind of magic would occur and the whole
world would change overnight. Just that if the Gnat stuff is merged with
gcc, the odds of getting those things integrated in the compiler I use for
my embedded target improve dramatically. (Sort of like your odds of winning
the lottery going up dramatically the instant you buy the ticket. :-)
Clearly, someone has to pick up the pieces and compile them together (and do
the required testing & debugging!) but that would seem like a thing that
would be profitable to do. More front ends + more hosts + more targets =
more potential customers. (Last time I looked at Green Hills, their compiler
was doing that sort of thing...)

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Ben Brosgol" <brosgol@world.std.com> wrote in message
news:GC2EDt.28x@world.std.com...
> Below is Robert Dewar's response to some of Marin's comments in this
thread.
>
> Ben Brosgol
> Ada Core Technologies
> brosgol@gnat.com
>
> =====================================
> First, there is no problem in having g++ and gnat compilers on the same
> machine, many of our customers are using such a setup to compile mixed
> language programs.
>
> Second, Marin said:
>
> > Will this ever happen? Ada being part of the regular gcc distribution,
> > that is. It would seem like it would be putting Ada in front of lots
more
> > people - don't know what that may do so the ACT business model,
though...)
>
> Read the gcc mailing list archives to know more about the plans and
progress
> here. I am not sure what the reference to the ACT business model is about,
> we don't see it as having any significant relevance. Our typical customers
> are definitely not interested in building their own unsupported untested
> versions of GNAT from source using the latest snapshots. The purpose of
> including GNAT in the gcc releases is multi-fold, most notably it means
that
> it is easier for GCC developers to ensure that their changes do not
> discombobulate GNAT. As to whether it will put Ada in front of lots more
> people, not so clear, remember that the gcc site only distributes sources,
> not binaries. So someone has to build binaries and make them available,
just
> as is the case now.
>
> > The big advantage I would have with a common GNAT/gcc would be that the
> > Cygnus compiler would suddenly start translating Ada code for my Mips
> > embedded processor - making it possible to substitute Ada where now C
> > exists. But I'd expect it would take a good long time for that to
migrate
> > into my PC here at work...
>
> This is a significant misconception. GNAT will only work on targets to
which
> it has been ported, just as is the case now, Marin seems to think some
magic
> will occur that will automatically generate working GNAT's on all machines
> for which gcc ports exist, but that obviously is not the case.
>
> Robert Dewar
> Ada Core Technologies
>
>
>