The libtraceevent package prior to version 5.9-1 was missing a soname link. This has been fixed in 5.9-1, so the upgrade will need to overwrite the untracked files created by ldconfig. If you get any of these errors
libtraceevent: /usr/lib/libtraceevent.so.1 exists in filesystem
when updating, use
pacman -Syu --overwrite /usr/lib/libtraceevent.so.1
to perform the upgrade.