/usr/include/gecode/search/ is in libgecode-dev 5.1.0-2build1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/gecode/search/bab.hpp
/usr/include/gecode/search/base.hpp
/usr/include/gecode/search/build.hpp
/usr/include/gecode/search/cutoff.hpp
/usr/include/gecode/search/dfs.hpp
/usr/include/gecode/search/engine.hpp
/usr/include/gecode/search/exception.hpp
/usr/include/gecode/search/lds.hpp
/usr/include/gecode/search/meta/
/usr/include/gecode/search/meta/dead.hh
/usr/include/gecode/search/meta/nogoods.hh
/usr/include/gecode/search/meta/parallel/
/usr/include/gecode/search/meta/parallel/pbs.hh
/usr/include/gecode/search/meta/parallel/pbs.hpp
/usr/include/gecode/search/meta/rbs.hh
/usr/include/gecode/search/meta/rbs.hpp
/usr/include/gecode/search/meta/sequential/
/usr/include/gecode/search/meta/sequential/pbs.hh
/usr/include/gecode/search/meta/sequential/pbs.hpp
/usr/include/gecode/search/options.hpp
/usr/include/gecode/search/parallel/
/usr/include/gecode/search/parallel/bab.hh
/usr/include/gecode/search/parallel/dfs.hh
/usr/include/gecode/search/parallel/engine.hh
/usr/include/gecode/search/parallel/path.hh
/usr/include/gecode/search/pbs.hpp
/usr/include/gecode/search/rbs.hpp
/usr/include/gecode/search/relax.hh
/usr/include/gecode/search/sebs.hpp
/usr/include/gecode/search/sequential/
/usr/include/gecode/search/sequential/bab.hh
/usr/include/gecode/search/sequential/dfs.hh
/usr/include/gecode/search/sequential/lds.hh
/usr/include/gecode/search/sequential/path.hh
/usr/include/gecode/search/statistics.hpp
/usr/include/gecode/search/stop.hpp
/usr/include/gecode/search/support.hh
/usr/include/gecode/search/traits.hpp
/usr/include/gecode/search/worker.hh