PostgreSQL: pg_upgrade failing because hstore incompatible

I'm trying to migrate from PostgreSQL 9.4.5_2 -> 9.5.3 I'm trying to use pg_upgrade (from 9.5.3 distribution) and getting the following error: pg_dump: [archiver (db)] query failed: ERROR: incompatible library "/usr/local/lib/postgresql/hstore.so": version mismatch Anyone know how to fix this? must I pg_dumpall and then reload? That has worked in the past. Trying to use pg_upgrade to save some steps.