I want to write a plugin for an open-source software which is not GPL, but has a GPL-compatible license (MIT/BSD). I would like the plugin to use a GPL library.
Can I do this?
- Since the plugin links with a GPL library, the plugin is of course also GPL, which is fine.
- In order to comply with GPL, all the components used to produce my plugin binaries need to be open-source with a GPL-compatible license.
- In order to build my plugin I also need to link with the host interface library (i.e. my plugin depends on this library).
- Because (and only because) this host interface library is also open-source under a GPL-compatible license (MIT), then I'm fine and my plugin can safely be distributed also under the GPL.
Is this reasoning correct?