On Thu, Jan 23, 2014 at 1:28 PM, Basile Starynkevitch <bas...@starynkevitch.net> wrote: > > Reminder: IANAL, ie I (Basile) am not a lawyer! But I am a free software > enthusiast and I like a lot the GPLv3.... > > As you know, GCC has some technical devices to invite plugin developers > to make GPL compliant plugins. > http://gcc.gnu.org/onlinedocs/gccint/Plugin-API.html > > This is done thru the plugin_is_GPL_compatible symbol. Of course, some > dishonest person could technically have & distribute a proprietary GCC > plugin defining that symbol (IANAL, but I believe it won't be accepted > in court, even if technically feasible).
The plugin_is_GPL_compatible symbol is implemented by GCC and may serve as an indication of intent by plugin developers. But it does not by itself indicate whether a plugin may be used. The rules for plugins are spelled out in the GCC Runtime Library Exception (http://www.gnu.org/licenses/gcc-exception-3.1.html). A plugin that follows those rules adds no restrictions to the generated code. A plugin that does not follow those rules does add restrictions to the generated code. This is true whether or not the plugin does anything with the plugin_is_GPL_compatible symbol. > Do meta-plugins like MELT (& probably Python plugin) should be concerned > about having some device to check compatibility with GPL licensing? I > believe that yes... (David Malcolm: what is your feeling on this? How do > you deal with that concern inside your Python plugin?) I think it would be reasonable for you to use something like plugin_is_GPL_compatible. > Can I just leave a warning, not an error, when the MELT macro > module_is_gpl_compatible is not used in some user-provided *.melt code? If you are going to use it, then use it. Make it an error. > Are my warning messages good enough; should I speak of "claim to be GPL > compatible" in them, or should it be something else, e.g. "assert to be > GPL compatible" or "promise to be GPL compatible", or "is GPL > compatible" [which cannot be technically checked, only legally!]; please > recall that English is not my native language! So any better suggestions > are welcome! Hard to give an opinion on an incomplete phrase, but copying the error message in gcc/plugin.c ought to be fine. > Is it ok or good to give the > http://www.gnu.org/licenses/gcc-exception-3.1.en.html URL in a notice > message? Yes, I think that is a good idea. Hope this helps. Ian
