The libbloom package prior to version 1.6-2 was missing a soname link. This has been fixed in 1.6-2, so the upgrade will need to overwrite the untracked soname link created by ldconfig. If you get an error
libbloom: /usr/lib/libbloom.so.1 exists in filesystem
when updating, use
pacman -Suy --overwrite usr/lib/libbloom.so.1
to perform the upgrade.