pg_upgrade was recently broken for use upgrading from a system with adminpack installed.
Breaking commit is:
commit 30982be4e5019684e1772dd9170aaa53f5a8e894
Integrate pg_upgrade_support module into backend
from pg_upgrade_dump_12870.log
pg_restore: creating EXTENSION "adminpack"
pg_restore: creating COMMENT "EXTENSION "adminpack""
pg_restore: [archiver (db)] Error while PROCESSING TOC:
pg_restore: [archiver (db)] Error from TOC entry 2806; 0 0 COMMENT EXTENSION "adminpack"
pg_restore: [archiver (db)] could not execute query: ERROR: extension "adminpack" does not exist
Command was: COMMENT ON EXTENSION "adminpack" IS 'administrative functions for PostgreSQL';
I get the same error whether the source database is 9.2.10 or 9.5.HEAD.
Cheers,
Jeff