function pg_describe_object(oid, oid, integer) does not exist

[andrecf]

When I try to run in the database the sql/install.sql script, I get the following error:

psql:sql/schema/pov/views/pg_depend_dot.sql:35: ERROR: function pg_describe_object(oid, oid, integer) does not exist
LINE 5: pg_describe_object(
^

To solve it, I have added one line at the sql/install.sql (adding the script that creates that function):

...
-- Internal views
\i sql/schema/pov/views/pg_all_objects_unique_columns.sql
\i sql/schema/pov/views/pg_depend_remapped.sql
\i sql/schema/pov/views/pg_depend_oid_concat.sql

-- catalog function
\i sql/schema/pg_catalog/functions/pg_describe_object.sql

-- internal views - continuation
\i sql/schema/pov/views/pg_depend_dot.sql
\i sql/schema/pov/views/pg_depend_tsort.sql
\i sql/schema/pov/views/pg_depend_definitions.sql
....

It did solve the problem, but trying to run:
select * from pov();

I get the following error from postgresql:

ERROR: cycle detected at line 320.
CONTEXTO: PL/Perl function "tsort"
SQL statement "SELECT Set_Revision(ObjectIDs) FROM (
-- Make array of all objects
SELECT
array_agg(ObjectID) AS ObjectIDs
FROM (
-- Create new ObjectID for each function.
-- If a object already exists with the same content (function definition), its ObjectID will be selected.
SELECT Set_Object(ARRAY[create_definition,drop_definition],description) AS ObjectID FROM pov.pg_depend_definitions
WHERE create_definition IS NOT NULL AND drop_definition IS NOT NULL AND description ~ '^(constraint|default|function|trigger|view)'
ORDER BY row_number
) AS Objects
) AS Revision"
PL/pgSQL function "new_revision" line 8 at SQL statement
PL/pgSQL function "pov" line 10 at assignment

is it difficult to solve this problem?