Re: License and Compiler Confusion

[Martin Krischik <krischik@users.sourceforge.net>]

Jason C. Wells wrote:

> I am a FreeBSD user.  I was thinking of picking up a language and I am
> considering Ada.  I came across this:
> 
> http://www.freebsd.org/cgi/url.cgi?ports/lang/gnat/pkg-descr
> 
> Binaries built with this version of compiler are covered by the
> GPL license.  Use the Ada compiler bundled with GCC 4.0 and
> subsequent for LGPL licensing.

Actually the compiler license is of no importance once the compiler finished
it's work. The resulting program can be of any license you like. However -
most compilers also provide a library some base functionality. And the
license of this library is of corse of great importance. In Ada you can
switch the use of that library off with "#pragma No_Runtime;" but then even
"Hello, World!" would not link any more.

The Ada runtime library comes with the GMGPL which is pretty permissive and
similar to the LGPL. Why not the LGPL? The LGPL is written for C and C has
no templates/generics - but Ada has.

> I also read the FAQ at adacore:
> 
> https://libre2.adacore.com/dynamic/gnat_faq.html#licensing

That's only for the Libre distributed runtime library of GNAT. For some
unknown reason they come with a stricter license then the FSF. But they are
not available for FreeBSD anyway so don't worry.

> I prefer to use a compiler that doesn't encumber my programs with any
> terms.  So I am confused by seemingly contradictory statements.  One
> source says I can't use gnat without encumbering my programs.  Another
> source says I can use gcc and my programs won't be encumbered.

Well depends where you download your sources from. Download from 
gcc.gnu.org and you get a permissive license, download from
libre.adacore.com and you get a more restricted license.

Why? We don't know, we can only guess from the fact that Libre is sponsored
by AdaCore the original maintainer of GNAT. And AdaCore has also a
professional version of GNAT called GNAT Pro for which they sell support.

> Are gcc and gnat two different pieces of software?  I was under the
> impression that gnat was simply gcc with Ada related tweaks.

Tweaks? GNAT is an Ada frontend to gcc. Just like g++ or gfortran. I would
not consider a frontend a "tweak". A frontend is a very big pice of code.

> Can I write Ada 2005 programs without GPL-ing my code using a FOSS
> compiler?

Yes you can. But you should be aware the Ada 2005 is not quite finished yet
(there was some talk about changing the name to Ada 2006 ;-) ).

> How? 

Best is to use gcc 4.1. If it is not packaged for FreeBSD yet I suggest you
role your own. Join the GNU Ada team if you want to do that
(http://gnuada.sf.net).

Martin
-- 
mailto://krischik@users.sourceforge.net
Ada programming at: http://ada.krischik.com