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QtCS2015 LicensePolicy
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QTCS 2015 - Qt Project Licensing Policy Discussion
- 3rd Party Code
- We have a bunch and don't own it
- Identifying it can be a challenge
- Let the doc team know if there is undocumented 3rd part code!
- Where we host a complete license things are mostly ok, but chunks that have been copy/pasted are more problematic
- There are certain licenses that we know we don't want to use
- We need a better process and clearer policy for tracking the situation
- We can't use certain licenses
- We like BSD, MIT, X11
- Apart from these three we must be careful, the legalities are problematic for both FOSS and commercial licensing
- Anything with an attribution clause adds a requirement for everyone
- We have a bunch and don't own it
- Contract with KDE Free Qt Foundation restricts us from doing certain things
- We're currently talking with them about an updated agreement
- We would like to use LGPLv3 more widely than we do now
- KDE wants to be able to run GPLv2-only code -> conflicts with LGPLv3
- GPLv2-only licenses are used in a lot of places without a clause that allows KDE e.V. to relicense
- Some modules LGPLv2-only, e.g.WebKit/WebEngine
- Try to keep these in separate modules/repos
- Apache v2 is showing up more and more
- This is due to Android influence and some patent protection clauses
- Thiago: "Everything coming out now is Apache v2"
- We use Apache v2 libraries in the Android styling code
- Apache v2 is not compatible with LGPLv2 -> forces LGPLv3
- Can be problematic for example with back-ends that use plugins (multimedia, sensors, etc)
- If you happen to load a plugin that links to something licensed under Apache v2
- This is due to Android influence and some patent protection clauses
- Until things are clarified with KDE don't touch core modules, but entirely new functionality can be licensed with LGPLv3
- Talked about doing something like the Linux kernel, tracking licenses of modules
- Nobody seemed to like this, would push burden onto users
- Difficult to maintain
- It's turtles all the way down, you would have to mark everything, also outside Qt
- We need policies and recommendations
- When and where Apache v2 dependencies are OK?
- Probably not to be used in Qt core
- What is the recommended licensing?
- The Qt Company would like LGPLv3, GPLv2 + Commercial for new modules
- Through CLA things can in principle be relicensed
- When and where Apache v2 dependencies are OK?
- What about things other than libaries?
- Examples are BSD-licensed so the code can be reused easily
- It might be good to relicense the tools under GPL (without the L)
- LGPL is increasingly seen as a free beer license and can result in misunderstandings - GPL is better understood
- QtCreator plugin interface would still have a clause permitting plugins licensed under different license
- KDevelop developers asked if this impacts them, consensus seemed to be no impact
- The Qt Company has some modules that are currently closed and would like to open under GPLv3
- Unclear whether contract with KDE Free Qt Foundation allows that or not, what is the KDE response?
- Jokingly: "Just put it on github and pretend it came from someone else"
- Thiago with his Intel hat on mentioned that GPL could be problematic in internal verification as people just say they use Qt, without specifying the modules individually
- "Just don't put GPLv3 in Qt5 git"