Can't use with GPLv2 under LGPLv3? [LWN.net]

Can't use with GPLv2 under LGPLv3?

Posted Jul 9, 2007 22:41 UTC (Mon) by sepreece (subscriber, #19270)
In reply to: Can't use with GPLv2 under LGPLv3? by Los__D
Parent article: Samba Adopts GPLv3 for Future Releases

Can you explain why you wouldn't be allowed to? The quoted exception allows you to link with libraries provided by the platform, regardless of their license and the LGPLv3 allows linking with material under any license (under certain conditions), so where's the blockage?

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Read the last sentence of that paragraph

Posted Jul 10, 2007 0:07 UTC (Tue) by JoeBuck (subscriber, #2330) [Link]

The GPLv2 text says:

However, as a special exception, the source code distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable (emphasis mine).

That means that a distro cannot include both the GPLv2-only app and the LGPLv3-or-later library, packaged so that the former uses the latter: you can't ship them together. The exception was for GPLv2 programs using proprietary C libraries, so it's written narrowly; it's caused problems for "GNU/Solaris" distributions. As it turns out, GPLv3 is more permissive in this regard.

Can't use with GPLv2 under LGPLv3?

Posted Jul 10, 2007 13:45 UTC (Tue) by jamesh (subscriber, #1159) [Link]

The system library exception essentially says that it is okay to distribute binaries of a GPL'd programs even if they link against system libraries that would not themselves be distributable under the GPL.

However, this would not really help you if the system library had a license that did not give permission to link against GPL'd programs.

So this would be a problem if you had a GPLv2-only application linking against the GPLv3 libsmbclient, as the application code is incompatible with libsmbclient's license.