possible readline license problem with ghc and -package util

Andre Pang ozone@algorithm.com.au
Wed, 12 Jun 2002 20:01:41 +1000

On Wed, Jun 12, 2002 at 10:10:15AM +0200, Wolfgang Thaller wrote:

> >     3. Developer wins because lots of people like the GPL, and 
> >        any development they do with the GPL is guaranteed to go 
> >        back to the community.  This may not occur all the time if 
> >        you only use a permissive license like the BSD license. 
> I'm slightly afraid of this. What will prevent a code split between the 
> GPL and BSD versions? 

In theory, nothing can prevent a code split between the GPL and
BSD versions.  In practice, you will find that this does not
happen.  Keep in mind that there's already nothing stopping
people from taking the current version of GHC and turning it into
a GPL work, or proprietry software; see my next paragraph.

> (Developer loses because other developers will contribute patches only 
> for the GPLed version. The GPL version will take all the code from the 
> BSD version, but the BSD version will automatically stay behind. If a 
> Developer wants to work on the cutting edge, they will have to work on 
> the GPL version, with no choice but to release their own patches under 
> GPL. In the end, only the GPL version will be left. User loses because 
> they will have to deal with the GPL after all.) 

There's already nothing which prevents this scenario with the
current (BSD) license.  People are free, right now, to take the
GHC code, make their own additions, and declare their work under
the GPL license.  If Microsoft want to release Visual GHC or
something, there's nothing stopping them from taking the current
code, making it all proprietry, and releasing it again.

So, in practice, a BSD/GPL code split won't happen.  I'd say that
Visual GHC being released is a more likely scenario (although
Simon and Simon may disagree ;).

One of the best things (and worst things) of the BSD license is
that really, people can do absolutely anything they want with it.

> > Maybe Perl can help Haskell in some slightly less evil ways ;). 
> Evil ways? Are you referring to that evil, carnivorous script 
> "ghc-asm.lprl"? Well, in my experience the "Evil Mangler" is just like 
> any other wild animal: he smells your fear. If you approach him without 
> fear, he won't harm you :-) 

Hey, I like Perl 8).  A lot.  I'm sure I'm not the only one on
this list who loves Perl and Haskell (and Vim and Emacs, and
Windows and Unix ...)

> My proposal would be as follows: 
> 1) seperate the readline library from the utils package. 
> 2) put a warning on the readline package so that people who are not 
> fluent in licenses won't accidentally use it for proprietary programs. 
> 3) Make sure that the Windows version links with libgmp dynamically. 
> 4) Leave GHCi as is. 

You can't leave GHCI as it is, because is currently links against
readline, which means that it must have a GPL license.

Your suggestions are fine for the users of GHC, who might not be
aware that they're linking with a GPLed library -- but the other
problem is that GHC itself has links against it.

I will agree that adding the warning on the readline package is
a good idea anyway.

#ozone/algorithm <ozone@algorithm.com.au>          - trust.in.love.to.save