Uninstall script errors

Several of the new uninstall scripts give errors, particularly those
that drop types and their support objects.  To see an example:

createdb foo
psql -d foo -f ltree.sql
psql -d foo -f uninstall_ltree.sql

A lot of the errors are due to DROP OPERATOR CLASS lines missing
the required USING clause; since that line fails so do subsequent
DROP OPERATOR and DROP FUNCTION lines because the operator class
still exists.  I've found a few other errors as well, such as a
CREATE TYPE line in uninstall_dblink.sql and a couple of DROP
FUNCTION lines in uninstall_btree_gist.sql for functions that were
never created.  I started to work on a patch but I wasn't sure how
to handle the chicken-and-egg situation of dropping a type and its
I/O functions.  Is there any way to do that other than DROP TYPE
CASCADE?  Should the uninstall scripts be doing that?

-- 
Michael Fuhr