Can I use some GPL code in LGPL project?

Question

Well, recently I found a problem about licensing.
I have an open source project on GitHub, recently I need some codes which using GNU GPL, but my project is using GNU LGPL, so that's the problem.
So how can I use these code? I don't want to change my license. Ask for permission from the original developpers or?

Answer 1

The combination of GPL code and LGPL code must be licensed under the GPL. If you want to use that code, you'll have to change your license, or refrain from using it. If the other project would want their code to be used in LGPL projects, they'd have licensed it under the LGPL – I doubt they'll give you special permission.

The LGPL is the same as the GPL plus some extra permissions. The key difference is that the LGPL strips the GPL from most of its “virality”. But the only reason to use the GPL instead of another license is that it forces dependent code to also be licensed under the GPL. It is therefore possible to use LGPL code in a GPL project but not the other way round.