/usr/lib/x86_64-linux-gnu/ is in libqt5waylandcompositor5-dev 5.7.1~20161021-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/cmake/
/usr/lib/x86_64-linux-gnu/cmake/Qt5WaylandCompositor/
/usr/lib/x86_64-linux-gnu/cmake/Qt5WaylandCompositor/Qt5WaylandCompositorConfig.cmake
/usr/lib/x86_64-linux-gnu/cmake/Qt5WaylandCompositor/Qt5WaylandCompositorConfigVersion.cmake
/usr/lib/x86_64-linux-gnu/cmake/Qt5WaylandCompositor/Qt5WaylandCompositor_.cmake
/usr/lib/x86_64-linux-gnu/libQt5WaylandCompositor.prl
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/Qt5WaylandCompositor.pc
/usr/lib/x86_64-linux-gnu/qt5/
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_waylandcompositor.pri
/usr/lib/x86_64-linux-gnu/libQt5WaylandCompositor.so