Re: LGPL Requirements (was: Selecting Ada95 compiler for MSDOS realtime application)

[dewar@merv.cs.nyu.edu (Robert Dewar)]

Thank you and others who have corrected my misunderstanding
of GNAT's license.  I had assumed that since the file "copying.lib"
is distributed with GNAT, it's requirements must apply to GNAT's
libraries.  I did not think to look at the file headers because I
wasn't aware that "special exceptions" to the GPL were permitted.

  Again, a huge misunderstanding of the GPL. Anyone holding a copyright
  can license things however they please. For instance, someone could
  use a license that allowed anyone but Microsoft to use a product free.
  The GPL is simply a starting point that you can use or not as you
  please, and modify anyway you like.

  Now the FSF is interested in free availability, so for software copyrighted
  by the FSF, it is unlikely that you would see peculiar restrictive versions
  of the GPL. The idea of the special exceptions is to extend the utility
  rather than to restrict it.

I work for a large corporation which currently discourages the use
of GNU software. The company lawyers have read the GPL and LGPL and
are nervous that we might unknowingly incorporate GPL'd software
into a product and then have customers requesting "our" software
under the terms of the GPL.

  Well you can't blame the lawyers if you give them the wrong information.
  They are right to worry about incorporating GPL'ed software and also, if
  you don't want to distribute object files, you should also avoid including
  anything that is copyrighted under the LGPL.

  In general, you have to be very careful about incorporating components
  into your software whose copyrights are held by others. This applies
  equally to any copyrighted software. For example, if you use a TSP
  compiler, then you are incorporating TSP copyrighted code into your
  application, and you should have your lawyers make sure that this
  does not cause you problems (I assume it does not, like ACT, TSP is
  interested in avoiding such problems).

  In the case of GNAT, you should also check carefully to make sure that
  the copyrighted units you include do not cause you trouble, but please
  give the right copyright statement to your lawyers, and not some
  entirely irrelevant stuff! 

I am trying to get this no-GNU policy changed. I need to understand
how GNAT's GPL license may or may not differ from that of plain gcc
or g77.  While I now understand that GNAT may be used to produce
propriatary,for-profit executables, the last sentence of the special
exception warns me to do so very carefully.

  No, you are not a lawyer probably, so you overreact to the last sentence.
  All this says is that you can't go including units covered by the normal
  GPL, and say "Hey, that's OK, I've got a unit here from GNAT that says
  everything is OK".
 
I have occasionally run into cases where lawyers do not understand the issues
clearly, and indeed many people are confused and read all sorts of things into
the GPL that are not there (for example, the adahome page says that GPL'ed
software cannot be sold -- which is of course nonsense). However, in this
case, it seems that your lawyers were giving you correct information about
something that does not in fact apply to you.

Note that the runtime code for other GNU compilers (e.g. g++) is also
distributed under specialized versions of the GPL designed to eliminate
problems with incorporation of runtime library code. The statement for
GNAT is a specialized one, that specifically addresses the concern about
generic instantiation.

We are currently preparing a Web page that will attempt to clarify these
issues in further detail. Meanwhile, a useful example to think about is
NextStep. At this stage, the only property that this company has is its
proprietary operating system software. This is entirely written using
GCC. There are many other such examples.

I also note that we have run into a number of situations where sales people
from other Ada vendors have, shall we say, rather peculiar notions about
GNU software and the GPL, and work hard to pass these peculiar notions
on to their customers :-)