/usr/include/xsd/cxx/tree/serialization/ is in xsdcxx 4.0.0-6.
This file is owned by root:root, with mode 0o755.
..
/usr/include/xsd/cxx/tree/serialization/boolean.hxx
/usr/include/xsd/cxx/tree/serialization/byte.hxx
/usr/include/xsd/cxx/tree/serialization/date-time.txx
/usr/include/xsd/cxx/tree/serialization/decimal.hxx
/usr/include/xsd/cxx/tree/serialization/double.hxx
/usr/include/xsd/cxx/tree/serialization/element-map.txx
/usr/include/xsd/cxx/tree/serialization/float.hxx
/usr/include/xsd/cxx/tree/serialization/int.hxx
/usr/include/xsd/cxx/tree/serialization/long.hxx
/usr/include/xsd/cxx/tree/serialization/short.hxx
/usr/include/xsd/cxx/tree/serialization/unsigned-byte.hxx
/usr/include/xsd/cxx/tree/serialization/unsigned-int.hxx
/usr/include/xsd/cxx/tree/serialization/unsigned-long.hxx
/usr/include/xsd/cxx/tree/serialization/unsigned-short.hxx