/usr/lib/x86_64-linux-gnu/ is in samba-dev 2:4.1.6+dfsg-1ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/dcerpc_server.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/netapi.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/dcerpc.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/torture.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/registry.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/samba-policy.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/ndr.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/smbclient-raw.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/dcerpc_atsvc.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/ndr_krb5pac.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/ndr_standard.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/gensec.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/samba-util.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/ndr_nbt.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/samba-hostconfig.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/dcerpc_samr.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/samdb.pc
/usr/lib/x86_64-linux-gnu/pkgconfig/samba-credentials.pc
/usr/lib/x86_64-linux-gnu/libsmbconf.so
/usr/lib/x86_64-linux-gnu/libndr.so
/usr/lib/x86_64-linux-gnu/libdcerpc-atsvc.so
/usr/lib/x86_64-linux-gnu/libsamba-policy.so
/usr/lib/x86_64-linux-gnu/libsamdb.so
/usr/lib/x86_64-linux-gnu/libdcerpc-binding.so
/usr/lib/x86_64-linux-gnu/libdcerpc-server.so
/usr/lib/x86_64-linux-gnu/libndr-standard.so
/usr/lib/x86_64-linux-gnu/libsmbclient-raw.so
/usr/lib/x86_64-linux-gnu/libsamba-hostconfig.so
/usr/lib/x86_64-linux-gnu/libtorture.so
/usr/lib/x86_64-linux-gnu/libdcerpc-samr.so
/usr/lib/x86_64-linux-gnu/libndr-nbt.so
/usr/lib/x86_64-linux-gnu/libgensec.so
/usr/lib/x86_64-linux-gnu/libpdb.so
/usr/lib/x86_64-linux-gnu/libsamba-credentials.so
/usr/lib/x86_64-linux-gnu/libsamba-util.so
/usr/lib/x86_64-linux-gnu/libregistry.so
/usr/lib/x86_64-linux-gnu/libdcerpc.so
/usr/lib/x86_64-linux-gnu/libndr-krb5pac.so
/usr/lib/x86_64-linux-gnu/libtevent-util.so
/usr/lib/x86_64-linux-gnu/libsmbldap.so
/usr/lib/x86_64-linux-gnu/libnetapi.so