pkg-config fails to find static library for zstd
Static build fails to find the libzstd.a library. This is because it uses pkg-config, and zstd's .pc file is missing .private tag. Please see the ticket I submitted: https://github.com/facebook/zstd/issues/719
You probably didn't test the static build with zstd. In any case, static build is broken due to this problem.