[systemd-devel] Systemd license vs. libcryptsetup license

[Uoti Urpala]

On Thu, 2017-06-08 at 17:14 +0000, Zbigniew Jędrzejewski-Szmek wrote:
> On Thu, Jun 08, 2017 at 06:03:37PM +0200, Julian Andres Klode wrote:
> > I'm not sure where you get that from. The usual interpretation is that
> > linking to a GPLed library means the linked work must be GPL as well.
> 
> I don't think that's true. It only must have a compatible license.

I think that is the default FSF position. There are at least some cases
where it's likely not automatic (for example, if there's a widespread
API/ABI that is provided by both GPLed and differently-licensed
libraries, an executable that works with both seems to have at least a
reasonable claim to not being a derivative work). However, assuming
that using a library may make the executable a derivative work seems to
be the only safe default assumption.

If the only thing you know is that some code uses the library, that may
mean things like nontrivial inline functions being included in the
compiled code, or copy relocations copying arbitrary amounts of data
into an executable. It seems pretty clear that this can be considered a
derived work. So I don't think you can ever claim that GPL wouldn't
cover the linked work without at least some analysis of the specific
library in question and how it's used in the program.