Justin Seyster <jrs...@gmail.com> writes: > 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.
GPLv3 is fine. > 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. The document is here: http://www.gnu.org/licenses/gcc-exception.html See also the rationale and FAQ that it links to. Basically, if you use a plugin with gcc, and the plugin is not GPL-compatible, then the resulting compiled code is covered by the GPL. > 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. That's pretty much it. > 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? Sure, both of those licenses are GPL-compatible. > 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. That is incorrect. You can link code under any GPL-compatible license with GPLv3 code, and the resulting executable will be covered the union of both licenses. Since GPLv3 tends to be stricter than any GPL-compatible license, this generally means that the result is under GPLv3. There is a (non-exhaustive) list of GPL-compatible licenses here: http://www.gnu.org/licenses/license-list.html#GPLCompatibleLicenses Ian
