Firstly, it's not a "problem" when code is released under the GPL. In many cases this is the best way to protect user freedom.
Secondly, this is the Lesser GPL, which means that only modifications to the FLIF implementation itself have to be free. It can still be linked in proprietary programs as long as they don't make any modifications.
It can be linked in proprietary programs even if they do make modifications, they just need to release the modified source code (of the LGPL library). The trickier obstacle is that it is required to be able to replace the LGPL library with another version in the proprietary program. I.e. the LGPL library must be dynamically linked, or the linkable compiled object code for the rest of the proprietary program must be provided so the program can be relinked statically.
> Firstly, it's not a "problem" when code is released under the GPL. In many cases this is the best way to protect user freedom.
Ah, thanks for the correction.
I went through a legal headache years ago releasing some software and our lawyers strongly urged against *GPL and pushed us to Apache because we would have had severely limited our opportunity for Fortune 500 companies. Apparently many prohibit anything with the letters GPL in the license, despite that the software was free and we were charging for services. It was a long headspinning debate and due to mounting legal fees we went with Apache.
> That means anything that touches it becomes LGPL, right?
Wrong, mostly.
Any changes you make to the encoder library itself would be LGPL, but if all you are doing is calling the library from other code then that is not an issue.
If you make a change to the library, even as part of a larger project, nothing else but that change is forced to be LGPL licensed. If your update is a bit of code you use elsewhere, as long as you own that code it does not force the elsewhere to be LGPL - while you are forced to LGPL the change to the library there is no stipulation that you can't dual license and use the same code under completely different terms outside the library.
Secondly, this is the Lesser GPL, which means that only modifications to the FLIF implementation itself have to be free. It can still be linked in proprietary programs as long as they don't make any modifications.