This file is indexed.

/usr/src/linux-headers-4.13.0-36-generic/ipc is in linux-headers-4.13.0-36-generic 4.13.0-36.40~16.04.1.

This file is owned by root:root, with mode 0o777.

It is a symlink to /usr/src/linux-headers-4.13.0-36-generic/../linux-headers-4.13.0-36/ipc