Postgres-R bits have not made their way into Postgres-XL, but some parts of Postgres-XC have. Some XC code is merged in to make future merging into Postgres-XL easier, even parts that are not used.
Some parts of Postgres-R are in the TransLattice Elastic Database (TED), but that is a proprietary closed source product, sorry. (I work for TransLattice, who also open sourced Postgres-XL.)
Ah, i see. It's a shame that no descendant of Postgres-R is open source, but i'm still pleased to hear that there is one, even if it's proprietary. Thanks for the information.
Some parts of Postgres-R are in the TransLattice Elastic Database (TED), but that is a proprietary closed source product, sorry. (I work for TransLattice, who also open sourced Postgres-XL.)