/etc/dpkg/shlibs.override is in dpkg-dev 1.19.0.5ubuntu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 | # dpkg shlibs override file
#
# Entries in this file will override all others, only use if you
# are really sure that is what you want!
#
# For more information see the dpkg-shlibdeps(1) manual page.
#
# <library name> <version/soname> <dependencies>
|