/usr/lib/ is in altree 1.3.1-5.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/perl5/
/usr/lib/x86_64-linux-gnu/perl5/5.26/
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Base.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/CUtils.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Chi2.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Foret.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Import.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Input.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Nanova.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Node.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Sens.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Site.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SiteCollection.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SitePerForet.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SitePerTree.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SiteSens.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SiteSensPerForet.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/SiteSensPerTree.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Tree.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/Utils.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/ALTree/to_rewrite.pm
/usr/lib/x86_64-linux-gnu/perl5/5.26/auto/
/usr/lib/x86_64-linux-gnu/perl5/5.26/auto/ALTree/
/usr/lib/x86_64-linux-gnu/perl5/5.26/auto/ALTree/CUtils/
/usr/lib/x86_64-linux-gnu/perl5/5.26/auto/ALTree/CUtils/CUtils.so
/usr/lib/x86_64-linux-gnu/perl5/5.26/auto/ALTree/CUtils/autosplit.ix