I'm getting ready to release plug-in code, and I want to have a very
clear idea about licensing before I release. I'm leaning towards
releasing everything as GPLv3, but I do want to know exactly what is
and isn't allowed.
I know this issue was debated quite intensely before plug-in support
got added, but my understanding is that there was a final consensus.
I can't find one document though that explains exactly what this
consensus was.
I vaguely remember a proposal that there would be no restriction on
plug-in licensing but that non-free plug-ins could only be used to
compile Free software, but that's not documented anywhere I can find.
GCC itself now requires that plug-ins export a
plugin_is_gpl_compatible symbol, which implies that the plug-in's
license need only be compatible with the GPL. Is it ok to release
LGPL- or BSD-licensed plug-ins?
My understanding is that, in general, only GPLv3 code can link against
GPLv3 code, which would imply that my plug-in code must be GPLv3.
The reason I ask is that other users of my code might want to make
derived works from it, and I want to be able to give them clear
answers about what licensing options they have. Thanks!
--Justin
