BUG #14650: pg_dump -c fails when 'public' schema doesn't exist

The following bug has been logged on the website:

Bug reference: 14650
Logged by: Arthur Nascimento
Email address: tureba(at)gmail(dot)com
PostgreSQL version: 9.6.3
Operating system: Linux - CentOS 7
Description:

Hi,

It seems that pg_dump -c fails when the database doesn't have a 'public'
schema. When using a clean database, then dropping (or renaming) the
'public' schema, a subsequent pg_dump -c tells me:

$ pg_dump -c test
pg_dump: [archiver (db)] query failed: ERROR: schema "public" does not
exist
LINE 1: ...::regclass AND pip.objsubid = 0 AND pip.objoid <> 'public'::...
^
pg_dump: [archiver (db)] query was: SELECT n.tableoid, n.oid, n.nspname,
(SELECT rolname FROM pg_catalog.pg_roles WHERE oid = nspowner) AS rolname,
(SELECT pg_catalog.array_agg(acl) FROM (SELECT
pg_catalog.unnest(coalesce(n.nspacl,pg_catalog.acldefault('n',n.nspowner)))
AS acl EXCEPT SELECT
pg_catalog.unnest(coalesce(pip.initprivs,pg_catalog.acldefault('n',n.nspowner))))
as foo) as nspacl, (SELECT pg_catalog.array_agg(acl) FROM (SELECT
pg_catalog.unnest(coalesce(pip.initprivs,pg_catalog.acldefault('n',n.nspowner)))
AS acl EXCEPT SELECT
pg_catalog.unnest(coalesce(n.nspacl,pg_catalog.acldefault('n',n.nspowner))))
as foo) as rnspacl, NULL as initnspacl, NULL as initrnspacl FROM
pg_namespace n LEFT JOIN pg_init_privs pip ON (n.oid = pip.objoid AND
pip.classoid = 'pg_namespace'::regclass AND pip.objsubid = 0 AND pip.objoid
<> 'public'::regnamespace)

This seems to have started in commit 330b84d8c4

A quick workaround is to create a schema called 'public' again, but I did
not expect the pg_dump error.

Thanks,
Arthur.