[librexpr]

> That's not it. Your license has to be GPL in order to use any GPL code. I try to make the stuff I do on my personal time under the MIT license, which means I can't use GPL code, but GPL code can incorporate my code. Tell me which license is more free now.

That's not how the GPL works. The GPL requires that you release the entire work under the GPL, but it does not forbid you from additionally releasing the parts you wrote under other licenses. So you can release the parts of the code you own under the MIT, as long as you also release the whole work under the GPL. [0]

> The other thing is that you can't use proprietary libraries in your own code that has been infected with GPL. If you want to develop your own software that incorporates GPL code and even release it to your users, it's impossible to link against proprietary libraries.

This is exactly the point of the GPL, and what, in my opinion, makes it more free than permissive licenses: GPL code will never restrict the user's freedom. Software that uses proprietary libraries is not free software, and so it is perfectly reasonable for it to be GPL-incompatible.

[0] https://www.gnu.org/licenses/gpl-faq.html#GPLModuleLicense