/usr/lib/ is in qtdeclarative5-private-dev 5.9.5-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/qt5/
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/
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/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_qml_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_qmldebug_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_qmldevtools_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_qmltest_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_quick_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_quickparticles_private.pri
/usr/lib/x86_64-linux-gnu/qt5/mkspecs/modules/qt_lib_quickwidgets_private.pri