Re: Not redistributing GNAT Pro (was: GWindows and a home for it)

[Simon Wright <simon@pushface.org>]

Ludovic Brenta <ludovic.brenta@insalien.org> writes:

> Customers are allowed to make changes to GNAT Pro and distribute
> their changes if they so choose, and they can even charge for that
> if they want.  The GMGPL guarantees them those rights.
> 
> I am not a supported customer of Ada Core's, but I can imagine several
> reasons why a customer would choose to respect Ada Core's request not
> to distribute their changes:
> 
> - They are not compiler businesses.  They are busy writing mission- or
>   life-critical software in Ada and have no time to devote to
>   modifying GNAT.  In fact, that's what they pay Ada Core for.
> 
> - They do not want to make it public that they use Ada.
> 
> - They do not want to put their reputation at stake, should their
>   modified GNAT Pro prove to be buggy.
> 
> - They do not want to fork away from GNAT Pro, because this would
>   cause maintenance nightmares.  And Ada software engineers know how
>   much that costs.
> 
> There may be other reasons as well which I have not thought of.  Would
> a supported customer care to enlighten us?

Those all sound reasonable reasons. But (for us) I personally think
the last is possibly the most important; the others aren't really on
the business's radar (it wouldn't occur to us to try selling Ada
compilers!)

As a current for-instance, we presently use a rebuilt RTS with (a) the
XDR version of System.Stream_Attributes, (b) an Ada.Command_Line that
doesn't raise exceptions on VxWorks (that's 3.16a1 only). This is all
very well, but we need to be sure that this rebuilt RTS is correct
(well, as correct as the supplied one). There are two ways I can see:
re-run ACATS ourselves, or pay ACT to do it. So it's an engineering
decision, to be preceded by asking ACT for a quote (today's job!)

By the way, thanks for the pointers in the Debian Ada Policy on the
inclusion of the ACATS subset in GCC.

-- 
Simon Wright                               100% Ada, no bugs.