A PL/JAVA NULL point reference has been reported by coverity scan.
The issue is located in guc.c for a pljava guc option
"pljava_classpath_insecure" and fixed in this commit.

tuple store which just advances current position by N instead of getting
tuple N times.

Author: Max Yang <myang@pivotal.io>

The timezone data in Greenplum are from the base version of
PostgreSQL that the current version of Greenplum is based on.
This cause issues since it means we are years behind on tz
changes that have happened. This pulls in the timezone data
and code from PostgreSQL 10.1 with as few changes to Greenplum
as possible to minimize merge conflicts. The goal is to gain
data rather than features, and for Greenplum for each release
to be able to stay current with the iana tz database as it is
imported into upstream PostgreSQL.

This removes a Greenplum specific test for the Yakutsk timezone
as it was made obsolete by upstream tz commit 1ac038c2c3f25f72.

This is mostly cherry-pick of upstream commit
commit 970a1868
Author: Robert Haas <rhaas@postgresql.org>
Date:   Fri Dec 3 08:44:15 2010 -0500

    Use GUC lexer for recovery.conf parsing.

    This eliminates some crufty, special-purpose code and, as a non-trivial
    side benefit, allows recovery.conf parameters to be unquoted.

    Dimitri Fontaine, with review and cleanup by Alvaro Herrera, Itagaki
    Takahiro, and me.

- detect primary goes down
- flip the role to m/p/d/n and p/m/u/n (role/prefer/status/mode) in
  gp_segment_configuration
- send promotion message to mirror to promote it

Author: Xin Zhang <xzhang@pivotal.io>
Author: Jacob Champion <pchampion@pivotal.io>
Author: Asim R P <apraveen@pivotal.io>

It set the master_mirroring_administrator_disable variable, but it's not
used for anything. Remove the variable, and all the code to pass that flag
through.

It was now unused.

gp_remove_segment_persistent_entries() function doesn't exist any more.

As a result of removing filespace, we need to pass the datadir instead.
That way, gp_add_segment_primary now matches gp_add_segment_mirror.

Author: Marbin Tan <mtan@pivotal.io>
Author: Jacob Champion <pchampion@pivotal.io>

We will not be supporting these utilities in GPDB 6.

References to gpcrondump and gpdbrestore in the gpdb-doc directory have been left
intact, as the documentation will be updated to refer to gpbackup and gprestore
in a separate commit.

Author: Jamie McAtamney <jmcatamney@pivotal.io>

Since persistent tables were removed, these were not used for anything.

- Special lock functions for RelationExtension
- Special function ReadBuffer_Resync()
- States related to CT and RESYNC
- Xlog during PageInit() for vacuum lazy (upstream doesn't have it so removed it)

This is a backport upstream commit 22817041, from PostgreSQL 9.0, which
added the server version number in the path. But in GPDB, also include the
gp_dbid in the path. This makes it possible to use the same tablespace path
on multiple servers running on the same host, without clashing.

Also includes cherry-pick of the small upstream cleanup commits 5c82ccb1
a6f56efc, and c282b36d.

Re-enable upstream 'tablespace' regression test. It works now, even when
all the nodes are running on same host.

Remove the concept of filespaces, revert tablespaces to work the same as
in upstream.

There is some leftovers in management tools. I don't know how to test all
that, and I was afraid of touching things I can't run. Also, we may need
to create replacements for some of those things on top of tablespaces, to
make the management of tablespaces easier, and it might be easier to modify
the existing tools than write them from scratch. (Yeah, you could always
look at the git history, but still.)

Per the discussion on gpdb-dev mailing list, the plan is to cherry-pick
commit 16d8e594 from PostgreSQL 9.2, to make it possible to have a
different path for a tablespace in the primary and its mirror. But that's
not included in this commit yet.

TODO: Make temp_tablespaces work.
TODO: Make pg_dump do something sensible, when dumping from a GPDB 5 cluster
that uses filespaces. Same with pg_upgrade.

Discussion: https://groups.google.com/a/greenplum.org/d/msg/gpdb-dev/sON4lraPEqg/v3lkM587BAAJ

GPDB skips databases that cannot be connected to in computing the oldest
database in vac_truncate_clog(). Make write_database_file() same, which was
reverted to upstream version. This helps to get the storage tests green for now.

Later can figure out and uniformly remove this code from vac_truncate_clog() and
write_database_file() if better solution is found to original issue for which
this check was added.

And the mechanism in initdb and gpinitsystem to set it. It's no longer
used for anything.

These were left over when Persistent Tables and Filerep were removed.

Revert the code to open/read/write regular files, to the way it's in the
upstream.

It's now unused.

I removed the autoconf flag and #ifdefs earlier, but missed these.

WAL replication is the name of the game on this branch.

They were not kept up-to-date anymore anyway. Remove the actual tables.

There are still a few references to these tables in the management tools.
AFAICS they're in tests, and I was hesitent to remove them just yet, in
case we're going to use the existing tests as a guide when writing new
tests.

The fault injection points used in the test didn't exist anymore. Add a new
injection point in RecordTransactionCommit(), just before writing the commit
WAL record, and use that in the test.

Remove a bunch of fault injection IDs that are no longer used. (They are
still referenced in some TINC tests, but the injection points don't exist
anymore, so those tests will need to be rewritten if we want to keep them.)

* Revert almost all the changes in smgr.c / md.c, to not go through
  the Mirrored* APIs.

* Remove mmxlog stuff. Use upstream "pending relation deletion" code
  instead.

* Get rid of multiple startup passes. Now it's just a single pass like
  in the upstream.

* Revert the way database drop/create are handled to the way it is in
  upstream. Doesn't use PT anymore, but accesses file system directly,
  and WAL-logs a single CREATE/DROP DATABASE WAL record.

* Get rid of MirroredLock

* Remove a few tests that were specific to persistent tables.

* Plus a lot of little removals and reverts to upstream code.

Another tricky removal but got through.

User of fault injector should set the fault at desired like master, primary or
mirror. Doesn't seem underneath fault injector code to be so heavy in checking
for right role.

Includes removal of changetrackingdump contrib module.

It wasn't very useful. The semaphore code is inherited from upstream, and
not likely to break any time soon. If you need this information during
debugging, use a debugger.

It didn't handle relation forks correctly, and counted the main fork's size
three times.