Status of GHC runtime dependency on GNU multi precisionarithmetic library

[Lars Oppermann]

On 8/16/07, Bayley, Alistair <Alistair_Bayley at invescoperpetual.co.uk> wrote:
> I could be wrong, but I believe that Brian's intention is indeed to
> release a commercial/proprietary app, hence it is possibly an issue for
> him. I'm not sure about having to distribute the code for his app; I
> thought the point of the LGPL license was to allow proprietary
> (non-GPL?) apps to link to LGPL libs. Wouldn't he just have to
> distribute the code for GMP? But then, I understand less about FSF
> licensing than pretty much everyone else on this list, so I'll shut up
> now...

As long as GMP isn't modified, it is not even necessary to distribute
the source code. It is only necessary to include the license
information as part of the "combined work". (Sect. 4 of LGPL).
Furthermore you need to make sure, that a user can replace the LGPL
component with another version. Dynamic linking is the easiest way to
do this. However, conveying object code that can be relinked
statically seems to be OK too. I cannot say that I get the definition
of "minimal corresponding code" in the LGPL completely.

The essence however seems to be that users must be able to replace the
LGPL component with another version. I also understand that it is not
necessary to include it directly in your binary distribution, as long
as you provide a mechanism through which the necessary material can be
obtained (e.g. separate download).

The idea is that if there is a bug in GMP but the author of the
combined work isn't willing or able to provide an updated version of
his app that is built with the fixed version, users must be able to
create their own version that uses the fixed GMP version.

Cheers,
/Lars