/usr/share/doc/llvm-3.6-dev/NEWS.Debian.gz is in llvm-3.6-dev 1:3.6.2-3ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/llvm-3.6-dev/../libllvm3.6v5/NEWS.Debian.gz
/usr/share/doc/llvm-3.6-dev/../libllvm3.6v5/NEWS.Debian.gz