"If you link statically or copy any of its code, then your program must be free software (GPL)." I don't the first part is true (the second one is though).
The second part isn't technically true either. You can copy code without requiring a license if you meet the requirements for fair use. For example, copying function signatures for interoperability.
I was trying to be conservative and paint a simplified picture of the license that you can't go wrong by following, but I definitely erred in leaving out some possibilities and presenting it as if they don't exist.
I was trying to be conservative and paint a simplified picture of the license that you can't go wrong by following, but I definitely erred in leaving out some possibilities and presenting it as if they don't exist.