/usr/share/doc/llvm-3.7-examples/Makefile.rules is in llvm-3.7-examples 1:3.7.1-2ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/llvm-3.7-examples/../../../lib/llvm-3.7/build/Makefile.rules