BUG #7906: pg_dump exits successfully after an error

The following bug has been logged on the website:

Bug reference: 7906
Logged by: Adam Tomjack
Email address: adam(dot)tomjack(at)zuerchertech(dot)com
PostgreSQL version: 9.2.1
Operating system: Linux 2.6.32-39-server #86-Ubuntu SMP x86_64
Description:

I have a database that uses a user-defined datatype. If the .so file
implementing that type is missing, pg_dump will fail when dumping a table
which uses that type, but it will still exit with status 0. The dump file
will be truncated and invalid.

Output:

pg_dump: Dumping the contents of table "foo" failed: PQgetResult() failed.
pg_dump: Error message from server: ERROR: could not access file
"bar-type": No such file or directory
pg_dump: The command was: COPY public.foo (baz) TO stdout;