kicad-developers team mailing list archive

[Andrew Zonenberg <azonenberg@xxxxxxxxxxxxxxx>]

My understanding is that LGPL can be DYNAMICALLY linked with arbitrarily
licensed code (GPL of any version, proprietary, permissive, etc) as long as:

1) any modifications to the LGPL'd module are redistributed under the
copyleft terms of the LGPL, and
2) patched/updated versions of the LGPL module can be freely swapped for
the original (no signature checks etc)

Static linking is a whole other can of worms because now you have a new
derived work which is a combination of the two. It may indeed be the
case that LGPL 2.1-only and GPL 3+ cannot be STATICALLY linked. But my
reading of the license does not in any way prohibit dynamic linking.

On 29/01/18 12:04, Wayne Stambaugh wrote:
> Hey Seth,
> 
> One of us missed something.  Here is my interpretation:
> 
> The opencascade website license states:
> 
> "Open CASCADE Technology version 6.7.0 and later are governed by GNU
> Lesser General Public License (LGPL) version 2.1 with additional exception."
> 
> It makes no mention of later versions of the LGPL (including the
> exception) so I am interpreting this as v2.1 only.  I do not have a copy
> (and I'm not going to sign up to get a copy so please check the
> copyright in the source to see if it matches the website) of the
> opencascade source archive to see if the license in the source
> specifically states "v2.1 or (at your option) any later version" which
> is typically how the GPL and LGPL are used.  If it does, than I can
> safely add this patch because I can make the claim that I am using
> opencascade under at later version of the LGPL which is compatible with
> the GPL 3 used by kicad.
> 
> According to the folks at the FSF:
> 
> "Please note that GPLv2 is, by itself, not compatible with GPLv3.
> However, most software released under GPLv2 allows you to use the terms
> of later versions of the GPL as well. When this is the case, you can use
> the code under GPLv3 to make the desired combination. To learn more
> about compatibility between GNU licenses, please see our FAQ."
> 
> I hope this clarifies why I am hesitant to merge this patch and what
> needs to clarified.  Isn't licensing fun! ;)
> 
> Thanks,
> 
> Wayne
> 
> On 1/29/2018 2:47 PM, Seth Hillbrand wrote:
>> Hi Wayne-
>>
>> My reading of your links is different.  Here's the relevant quote:
>>
>> "GNU Lesser General Public License (LGPL) version 2.1 (#LGPLv2.1) This
>> is the previous version of the LGPL: a free software license, but not a
>> strong copyleft license, because it permits linking with nonfree
>> modules. It is compatible with GPLv2 and GPLv3."
>>
>> Did I miss something?
>>
>> -Seth
>>
>> 2018-01-29 11:18 GMT-08:00 Wayne Stambaugh <stambaughw@xxxxxxxxx
>> <mailto:stambaughw@xxxxxxxxx>>:
>>
>>     Seth,
>>
>>     There maybe licensing issues involved with this.  OpenCascade is
>>     licensed using LGPL v2.1 not v2.1[1] or later.  LGPL v2.1 is not
>>     compatible with GPL 3[2].  If OpenCascade is willing to change their
>>     license LPGL 2.1 or later or if this is just an oversight on their part,
>>     than I can include this patch.  Please verify the OpenCascade license
>>     with something that I can verify to ensure we are not violating and
>>     licensing terms.
>>
>>     Cheers,
>>
>>     Wayne
>>
>>     [1]: https://www.opencascade.com/content/licensing
>>     <https://www.opencascade.com/content/licensing>
>>     [2]:
>>     https://www.gnu.org/licenses/license-list.en.html#GPLCompatibleLicenses
>>     <https://www.gnu.org/licenses/license-list.en.html#GPLCompatibleLicenses>
>>
>>     On 1/29/2018 1:54 PM, Seth Hillbrand wrote:
>>     > ​Hi All-
>>     >
>>     > Currently, the build requires the opencascade community edition.  For
>>     > various reasons, I need to have the current non-community edition of
>>     > OpenCASCADE installed on my work machine.
>>     >
>>     > The attached patch allows compiling KiCad with either the OpenCASCADE
>>     > community edition or standard edition.  
>>     >
>>     > I've tested on a homebrew-based Mac install as well as Linux but
>>     haven't
>>     > verified MSW, if someone would be willing to test it there, that would
>>     > be great!  The basic search routines are lightly modified from
>>     FreeCAD's
>>     > logic and keep their LGPL copyright on the CMake file.
>>     >
>>     > -Seth​
>>     >
>>     >
>>     >
>>     > _______________________________________________
>>     > Mailing list: https://launchpad.net/~kicad-developers
>>     <https://launchpad.net/~kicad-developers>
>>     > Post to     : kicad-developers@xxxxxxxxxxxxxxxxxxx
>>     <mailto:kicad-developers@xxxxxxxxxxxxxxxxxxx>
>>     > Unsubscribe : https://launchpad.net/~kicad-developers
>>     <https://launchpad.net/~kicad-developers>
>>     > More help   : https://help.launchpad.net/ListHelp
>>     <https://help.launchpad.net/ListHelp>
>>     >
>>
>>     _______________________________________________
>>     Mailing list: https://launchpad.net/~kicad-developers
>>     <https://launchpad.net/~kicad-developers>
>>     Post to     : kicad-developers@xxxxxxxxxxxxxxxxxxx
>>     <mailto:kicad-developers@xxxxxxxxxxxxxxxxxxx>
>>     Unsubscribe : https://launchpad.net/~kicad-developers
>>     <https://launchpad.net/~kicad-developers>
>>     More help   : https://help.launchpad.net/ListHelp
>>     <https://help.launchpad.net/ListHelp>
>>
>>
>>
>>
>> _______________________________________________
>> Mailing list: https://launchpad.net/~kicad-developers
>> Post to     : kicad-developers@xxxxxxxxxxxxxxxxxxx
>> Unsubscribe : https://launchpad.net/~kicad-developers
>> More help   : https://help.launchpad.net/ListHelp
>>
> 
> _______________________________________________
> Mailing list: https://launchpad.net/~kicad-developers
> Post to     : kicad-developers@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~kicad-developers
> More help   : https://help.launchpad.net/ListHelp
>