During a replication slot creation, an ERROR generated in the same
transaction as the one creating a to-be-exported snapshot would have
left the backend in an inconsistent state, as the associated static
export snapshot state was not being reset on transaction abort, but only
on the follow-up command received by the WAL sender that created this
snapshot on replication slot creation.  This would trigger inconsistency
failures if this session tried to export again a snapshot, like during
the creation of a replication slot.

Note that a snapshot export cannot happen in a transaction block, so
there is no need to worry resetting this state for subtransaction
aborts.  Also, this inconsistent state would very unlikely show up to
users.  For example, one case where this could happen is an
out-of-memory error when building the initial snapshot to-be-exported.
Dilip found this problem while poking at a different patch, that caused
an error in this code path for reasons unrelated to HEAD.

Author: Dilip Kumar
Reviewed-by: Michael Paquier, Zhihong Yu
Discussion: https://postgr.es/m/CAFiTN-s0zA1Kj0ozGHwkYkHwa5U0zUE94RSc_g81WrpcETB5=w@mail.gmail.com
Backpatch-through: 9.6

Commit f0e21f2f6 missed adding a tgisinternal output column
to getTriggers' query for pre-8.3 servers.  Back-patch to v11,
like that commit.

It was clearly the intent to do so all along, but the original coding
fat-fingered this by checking the wrong array element.  We fixed it
in passing in 403a3d91, but that later got reverted, and we forgot
to keep this bug fix.

Most of the time this'd be relatively harmless, since once we lock
any of the partitioned table's leaf partitions, that would suffice
to prevent major DDL on the partitioned table itself.  However, a
childless partitioned table would get dumped with no relevant lock
whatsoever, possibly allowing dump failure or inconsistent output.

Unlike 403a3d91, there are no versioning concerns, since every server
version that has partitioned tables will allow you to lock one.

Back-patch to v10 where partitioned tables were introduced.

Discussion: https://postgr.es/m/1018205.1634346327@sss.pgh.pa.us

Backpatch to 14 where install_path was introduced.

Recent pg_amcheck bugfix commit d2bf06db added a test case that the
buildfarm has shown to be non-portable.  It doesn't particularly seem
worth keeping anyway.  Remove it.

Discussion: https://postgr.es/m/CAH2-Wz=7HKJ9WzAh7+M0JfwJ1yfT9qoE+KPa3P7iGToPOtGhXg@mail.gmail.com
Backpatch: 14-, just like the original commit.

An extension may want to call GetSecurityLabel() on a shared object
before the shared relcaches are fully initialized. For instance, a
ClientAuthentication_hook might want to retrieve the security label on
a role.

Discussion: https://postgr.es/m/ecb7af0b26e3be1d96d291c8453a86f1f82d9061.camel@j-davis.com
Backpatch-through: 9.6

If a function-in-FROM laterally references the output of some sub-SELECT
earlier in the FROM clause, and we are able to flatten that sub-SELECT
into the outer query, the expression(s) copied into the function RTE
missed being processed by eval_const_expressions.  This'd lead to trouble
and probable crashes at execution if such expressions contained
named-argument function call syntax or functions with defaulted arguments.
The bug is masked if the query contains any explicit JOIN syntax, which
may help explain why we'd not noticed.

Per bug #17227 from Bernd Dorn.  This is an oversight in commit 7266d099,
so back-patch to v13 where that came in.

Discussion: https://postgr.es/m/17227-5a28ed1512189fa4@postgresql.org

The test code added with ff9f111bce24 fails under valgrind, and probably
other slow cases too, because if (say) autovacuum runs in between and
produces WAL of its own, the large INSERT fails to account for that in
the LSN calculations.  Rewrite to use a DO loop.

Per complaint from Andres Freund

Backpatch to all branches.

Discussion: https://postgr.es/m/20211013180338.5guyqzpkcisqugrl@alap3.anarazel.de

Avoid calling contrib/amcheck functions with relations that are
unsuitable for checking.  Specifically, don't attempt verification of
temporary relations, or indexes whose pg_index entry indicates that the
index is invalid, or not ready.

These relations are not supported by any of the contrib/amcheck
functions, for reasons that are pretty fundamental.  For example, the
implementation of REINDEX CONCURRENTLY can add its own "transient"
pg_index entries, which has rather unclear implications for the B-Tree
verification functions, at least in the general case -- so they just
treat it as an error.  It falls to the amcheck caller (in this case
pg_amcheck) to deal with the situation at a higher level.

pg_amcheck now simply treats these conditions as additional "visibility
concerns" when it queries system catalogs.  This is a little arbitrary.
It seems to have the least problems among any of the available
alternatives.

Author: Mark Dilger <mark.dilger@enterprisedb.com>
Reported-By: Alexander Lakhin <exclusion@gmail.com>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Bug: #17212
Discussion: https://postgr.es/m/17212-34dd4a1d6bba98bf@postgresql.org
Backpatch: 14-, where pg_amcheck was introduced.

The comments were misplaced when adding postgres_fdw.  Fix that by
moving the comments to more appropriate functions.

Author: Etsuro Fujita
Backpatch-through: 9.6
Discussion: https://postgr.es/m/CAPmGK164sAXQtC46mDFyu6d-T25Mzvh5qaRNkit06VMmecYnOA%40mail.gmail.com

The code was freeing the name of the multirange type function stored in
the parse tree but it should not do that.  Event triggers could for
example look at such a corrupted parsed tree with a ddl_command_end
event.

Author: Alex Kozhemyakin, Sergey Shinderuk
Reviewed-by: Peter Eisentraut, Michael Paquier
Discussion: https://postgr.es/m/d5042d46-b9cd-6efb-219a-71ed0cf45bc8@postgrespro.ru
Backpatch-through: 14

This fixes a set of issues that cause different breakages or annoyances
when using pg_upgrade's test.sh to do upgrades across different major
versions:
- test.sh is completely broken when using v14 as new version because of
the removal of testtablespace/ as Makefile rule.  Older versions of
pg_regress don't support --make-tablespacedir, blocking the creation of
the tablespace.  In order to fix that, it is simple enough to create
those directories in the script itself, but only do that when an old
version is involved.  This fix is needed on HEAD and REL_14_STABLE.
- The script would fail when using PG <= v11 as old version because of
WITH OIDS relations not supported in v12.  In order to fix this, this
steals a method from the buildfarm that uses a DO block to change all
the relations marked as WITH OIDS, allowing pg_upgrade to pass.  This is
more portable than using ALTER TABLE queries on the relations causing
issues.  This is fixed down to v12, and authored originally by Andrew
Dunstan.
- Not using --extra-float-digits=0 with v11 as old version causes
a lot of diffs in the dumps, making the whole unreadable.  This gets
only done when using v11 as old version.  This is fixed down to v12.
The buildfarm code uses that already.

Note that the addition of --wal-segsize and --allow-group-access breaks
the script when using v10 or older at initdb time as these got added in
11.  10 would be EOL'd next year and nobody has complained about those
problems yet, so nothing is done about that.  This means that this
commit fixes upgrade tests using test.sh with v11 as minimum older
version, up to HEAD, and that it is enough to apply this change down to
12.  The old and new dumps still generate diffs, still require manual
checks, and more could be done to reduce the noise, but this allows the
tests to run with a rather minimal amount of them.

I have tested this commit and test.sh with v11 as minimum across all the
branches where this is applied.  Note that this commit has no impact on
the normal pg_upgrade test run with a simple "make check".

Author:  Justin Pryzby, Andrew Dunstan, Michael Paquier
Discussion: https://postgr.es/m/20201206180248.GI24052@telsasoft.com
Backpatch-through: 12

Author: Pavel Luzanov <p.luzanov@postgrespro.ru>
Discussion: https://postgr.es/m/c71a3cfc-a267-3d9f-1b44-fbd668d0ab10@postgrespro.ru
Backpatch: 14-, where the failsafe was introduced.

Incrementing the level of the call stack reported is useful for
debugging purposes as it allows to control which part of the test is
exactly failing, especially if a test is structured with subroutines
that call routines from Test::More.

This adds more incrementations of $Test::Builder::Level where debugging
gets improved (for example it does not make sense for some paths like
pg_rewind where long subroutines are used).

A note is added to src/test/perl/README about that, based on a
suggestion from Andrew Dunstan and a wording coming from both of us.

Usage of Test::Builder::Level has spread in 12, so a backpatch down to
this version is done.

Reviewed-by: Andrew Dunstan, Peter Eisentraut, Daniel Gustafsson
Discussion: https://postgr.es/m/YV1CCFwgM1RV1LeS@paquier.xyz
Backpatch-through: 12

Previously when pg_log_backend_memory_contexts() sent the request to
the autovacuum launcher, it could take more than several seconds to
log its memory contexts. Because the function (HandleAutoVacLauncherInterrupts)
to process any new interrupts that autovacuum launcher received
didn't handle the request for logging of memory contexts. This commit changes
the function so that it handles the request, to make autovacuum launcher
more responsitve to pg_log_backend_memory_contexts().

Back-patch to v14 where pg_log_backend_memory_contexts() was added.

Author: Koyu Tanigawa
Reviewed-by: Bharath Rupireddy, Atsushi Torikoshi
Discussion: https://postgr.es/m/0aae3e074face409b35153451be5cc11@oss.nttdata.com

Have verify_heapam.c treat unlogged relations as if they were simply
empty when in Hot Standby mode.  This brings it in line with
verify_nbtree.c, which has handled unlogged relations in the same way
since bugfix commit 6754fe65.  This was an oversight in commit
866e24d4, which extended contrib/amcheck to check heap relations.

In passing, lower the verbosity used when reporting that a relation has
been skipped like this, from NOTICE to DEBUG1.  This is appropriate
because the skipping behavior is only an implementation detail, needed
to work around the fact that unlogged tables don't have smgr-level
storage for their main fork when in Hot Standby mode.

Affected unlogged relations should be considered "trivially verified",
not skipped over.  They are verified in the same sense that a totally
empty relation can be verified.  This behavior seems least surprising
overall, since unlogged relations on a replica will initially be empty
if and when the replica is promoted and Hot Standby ends.

Author: Mark Dilger <mark.dilger@enterprisedb.com>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzk_pukOFY7JmdiFLsrz+Pd3V8OwgC1TH2Vd5BH5ZgK4bA@mail.gmail.com
Backpatch: 14-, where heapam verification was introduced.

Commit 3f50b8263 had an oversight: formerly, to deparse expressions
attached to a plan node, it was only necessary to update the
deparse_namespace ancestors list alongside calling set_deparse_plan.
Now it's necessary to update the ancestors list *first*, because
set_deparse_plan consults it, and one call site got that wrong.

This error was masked in most cases because explain.c uses just one
List object for the ancestors list, updating it in-place as the plan
is scanned, so that we accidentally had the right List assigned to
dpns->ancestors before it was needed.  It would fail only if a
WorkTableScan node were the first one that we tried to deparse a
subexpression of.

Per report from Markus Winand.  Like the previous patch,
back-patch to v14.

Discussion: https://postgr.es/m/648B0505-AA57-42C2-A2DA-E551DE46FA15@winand.at

Commit 27e1f145 missed updating some comments.

Reviewed-by: Bharath Rupireddy
Backpatch-through: 14
Discussion: https://postgr.es/m/CAPmGK15Q2Nm6U%2Ba_GwskrWFEVBZ9_3VKOvRrprGufpx91M_3Sw%40mail.gmail.com

Author: Amit Langote
Backpatch-through: 13
Discussion: https://postgr.es/m/CA%2BHiwqGQNbtamQ_9DU3osR1XiWR4wxWFZurPmN6zgbdSZDeWmw%40mail.gmail.com

Commit c7b7311f6 adjusted conversion_error_callback to always use
information from the query's rangetable, to avoid doing catalog lookups
in an already-failed transaction.  However, as a result of the utterly
inadequate documentation for make_tuple_from_result_row, I failed to
realize that fsstate could be NULL in some contexts.  That led to a
crash if we got a conversion error in such a context.  Fix by falling
back to the previous coding when fsstate is NULL.  Improve the
commentary, too.

Per report from Andrey Borodin.  Back-patch to 9.6, like the previous
patch.

Discussion: https://postgr.es/m/08916396-55E4-4D68-AB3A-BD6066F9E5C0@yandex-team.ru

This fixes a loss of precision that occurs when the first input is
very close to 1, so that its logarithm is very small.

Formerly, during the initial low-precision calculation to estimate the
result weight, the logarithm was computed to a local rscale that was
capped to NUMERIC_MAX_DISPLAY_SCALE (1000). However, the base may be
as close as 1e-16383 to 1, hence its logarithm may be as small as
1e-16383, and so the local rscale needs to be allowed to exceed 16383,
otherwise all precision is lost, leading to a poor choice of rscale
for the full-precision calculation.

Fix this by removing the cap on the local rscale during the initial
low-precision calculation, as we already do in the full-precision
calculation. This doesn't change the fact that the initial calculation
is a low-precision approximation, computing the logarithm to around 8
significant digits, which is very fast, especially when the base is
very close to 1.

Patch by me, reviewed by Alvaro Herrera.

Discussion: https://postgr.es/m/CAEZATCV-Ceu%2BHpRMf416yUe4KKFv%3DtdgXQAe5-7S9tD%3D5E-T1g%40mail.gmail.com

Oversight in a3fcbcd.

Reported-by: Thomas Munro
Discussion: https://postgr.es/m/CA+hUKGKnajZEwe91OTjro9kQLCMGGFHh2vvFn8tgHgbyn4bF9w@mail.gmail.com
Backpatch-through: 13

queries.sgml failed to mention the rather important point that
INTERSECT binds more tightly than UNION or EXCEPT.  I thought
it could also use more discussion of the role of parentheses
in these constructs.

Per gripe from Christopher Painter-Wakefield.

Discussion: https://postgr.es/m/163338891727.12510.3939775743980651160@wrigleys.postgresql.org

The old URL was HTTP 404 and the git link didn't build.  Also update two
other ICU links.  If we ever get a good link we will add it back.

Reported-by: Anton Voloshin

Author: Laurenz Albe

Backpatch-through: 10

3c5b0685 used setFilePointer() to set the position of the filehandle, but
passed the wrong filehandle, always leaving the position at 0. Instead of just
fixing that, remove use of setFilePointer(), we have a perl fd at this point,
so we can just use perl's seek().

Additionally, the perl filehandle wasn't closed, just the windows filehandle.
Reviewed-By: Andrew Dunstan <andrew@dunslane.net>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20211003173038.64mmhgxctfqn7wl6@alap3.anarazel.de
Backpatch: 9.6-, like 3c5b0685

Per discussion, let's just follow CLDR's default zone mappings
faithfully.  There are two changes here that are clear improvements:

* Mapping "Greenwich Standard Time" to Atlantic/Reykjavik is actually
a better fit than using London, because Iceland hasn't observed DST
since 1968, so this is more nearly what people might expect.

* Since the "Samoa" zone is specified to be UTC+13:00, we must map
it to Pacific/Apia not Pacific/Samoa; the latter refers to American
Samoa which is now on the other side of the date line.

The rest of these changes look like they're choosing the most populous
IANA zone as representative.  Whatever the details, we're just going
to say "if you don't like this mapping, complain to CLDR".

Discussion: https://postgr.es/m/3266414.1633045628@sss.pgh.pa.us

gist.sgml and xindex.sgml hadn't been fully updated for the
addition of a sortsupport support function (commit 16fa9b2b).
xindex.sgml also missed that the compress and decompress support
functions are optional, an apparently far older oversight.

In passing, fix gratuitous inconsistencies in wording and
capitalization.

Noted by E. Rogov.  Back-patch to v14; the residual issues
before that aren't significant enough to bother with.

Discussion: https://postgr.es/m/163335322905.12519.5711557029494638051@wrigleys.postgresql.org

Some specific logic is done at the end of recovery when involving 2PC
transactions:
1) Call RecoverPreparedTransactions(), to recover the state of 2PC
transactions into memory (re-acquire locks, etc.).
2) ShutdownRecoveryTransactionEnvironment(), to move back to normal
operations, mainly cleaning up recovery locks and KnownAssignedXids
(including any 2PC transaction tracked previously).
3) Switch XLogCtl->SharedRecoveryState to RECOVERY_STATE_DONE, which is
the tipping point for any process calling RecoveryInProgress() to check
if the cluster is still in recovery or not.

Any snapshot taken between steps 2) and 3) would be empty, causing any
transaction relying on a snapshot at this point to potentially corrupt
data as there could still be some 2PC transactions to track, with
RecentXmin moving backwards on successive calls to GetSnapshotData() in
the same transaction.

As SharedRecoveryState is the point to take into account to know if it
is safe to discard KnownAssignedXids, this commit moves step 2) after
step 3), so as we can never finish with empty snapshots.

This exists since the introduction of hot standby, so backpatch all the
way down.  The window with incorrect snapshots is extremely small, but I
have seen it when running 023_pitr_prepared_xact.pl, as did buildfarm
member fairywren.  Thomas Munro also found it independently.  Special
thanks to Andres Freund for taking the time to analyze this issue.

Reported-by: Thomas Munro, Michael Paquier
Analyzed-by: Andres Freund
Discussion: https://postgr.es/m/20210422203603.fdnh3fu2mmfp2iov@alap3.anarazel.de
Backpatch-through: 9.6

Prior to v14, we insisted that the query in RETURN QUERY be of a type
that returns tuples.  (For instance, INSERT RETURNING was allowed,
but not plain INSERT.)  That happened indirectly because we opened a
cursor for the query, so spi.c checked SPI_is_cursor_plan().  As a
consequence, the error message wasn't terribly on-point, but at least
it was there.

Commit 2f48ede0 lost this detail.  Instead, plain RETURN QUERY
insisted that the query be a SELECT (by checking for SPI_OK_SELECT)
while RETURN QUERY EXECUTE failed to check the query type at all.
Neither of these changes was intended.

The only convenient place to check this in the EXECUTE case is inside
_SPI_execute_plan, because we haven't done parse analysis until then.
So we need to pass down a flag saying whether to enforce that the
query returns tuples.  Fortunately, we can squeeze another boolean
into struct SPIExecuteOptions without an ABI break, since there's
padding space there.  (It's unlikely that any extensions would
already be using this new struct, but preserving ABI in v14 seems
like a smart idea anyway.)

Within spi.c, it seemed like _SPI_execute_plan's parameter list
was already ridiculously long, and I didn't want to make it longer.
So I thought of passing SPIExecuteOptions down as-is, allowing that
parameter list to become much shorter.  This makes the patch a bit
more invasive than it might otherwise be, but it's all internal to
spi.c, so that seems fine.

Per report from Marc Bachmann.  Back-patch to v14 where the
faulty code came in.

Discussion: https://postgr.es/m/1F2F75F0-27DF-406F-848D-8B50C7EEF06A@gmail.com

This corrects a bunch of entries in win32_tzmap[], and adds a few
new ones, based on the CLDR project's windowsZones.xml file.
Non-cosmetic changes fall into four main categories:

* Flat-out errors:

US/Aleutan doesn't exist
America/Salvador doesn't exist
Asia/Baku is wrong for Yerevan
Asia/Dhaka (Bangladesh) is wrong for Astana (Kazakhstan)
Europe/Bucharest is wrong for Chisinau
America/Mexico_City is wrong for Chetumal
America/Buenos_Aires is wrong for Cayenne
America/Caracas has its own zone, so poor fit for La Paz
US/Eastern is wrong for Haiti
US/Eastern is wrong for Indiana (East)
Asia/Karachi is wrong for Tashkent
Etc/UTC+12 doesn't exist
Signs of Etc/GMT zones were backwards

* Judgment calls:

(These changes follow CLDR's choices, except for the first one)

Use Europe/London for "Greenwich Standard Time", since that seems much
more likely than Africa/Casablanca to be what people will think that
zone name means.  CLDR has Atlantic/Reykjavik here, but that's no better.

Asia/Shanghai seems a better fit than Hong Kong for "China Standard
Time".

Europe/Sarajevo is now a link to Belgrade, ie "Central Europe Standard
Time"; so use Warsaw for "Central European Standard Time".

America/Sao_Paulo seems more representative than Araguaina for
"E. South America Standard Time".

Africa/Johannesburg seems more representative than Harare for
"South Africa Standard Time".

* New Windows zone names:

"Israel Standard Time"
"Kaliningrad Standard Time"
"Russia Time Zone N" for various N
"Singapore Standard Time"
"South Sudan Standard Time"
"W. Central Africa Standard Time"
"West Bank Standard Time"
"Yukon Standard Time"

Some of these replace older spellings, but I kept the older spellings
too in case our code runs on a machine with the older data.

* Replace aliases (tzdb Links) with underlying city-named zones:

(This tracks tzdb's longstanding practice, and reduces inconsistency
with the rest of the entries, as well as with CLDR.)

US/Alaska
Asia/Kuwait
Asia/Muscat
Canada/Atlantic
Australia/Canberra
Canada/Saskatchewan
US/Central
US/Eastern
US/Hawaii
US/Mountain
Canada/Newfoundland
US/Pacific

Back-patch to all supported branches, as is our usual practice for
time zone data updates.

Discussion: https://postgr.es/m/3266414.1633045628@sss.pgh.pa.us

The original intent seems to have been to sort case-insensitively
by the Windows zone name, but various changes over the years did
not get that memo.  This commit just moves a few entries to
restore exact alphabetic order, to ease comparison to the outputs
of processing scripts.

Back-patch to all supported branches, as is our usual practice for
time zone data updates.

Discussion: https://postgr.es/m/3266414.1633045628@sss.pgh.pa.us

The previous approach didn't really work on windows, due to the PATH separator
being ';' not ':'. Instead of making the PATH change more complicated,
reference the binary using the TESTDIR environment.
Reported-By: Andres Freund <andres@anarazel.de>
Suggested-By: Andrew Dunstan <andrew@dunslane.net>
Discussion: https://postgr.es/m/20210930214040.odkdd42vknvzifm6@alap3.anarazel.de
Backpatch: 14-, where the test was introduced.

Both bugs #16676[1] and #17141[2] illustrate that the combination of
SKIP LOCKED and FETCH FIRST WITH TIES break expectations when it comes
to rows returned to other sessions accessing the same row.  Since this
situation is detectable from the syntax and hard to fix otherwise,
forbid for now, with the potential to fix in the future.

[1] https://postgr.es/m/16676-fd62c3c835880da6@postgresql.org
[2] https://postgr.es/m/17141-913d78b9675aac8e@postgresql.org

Backpatch-through: 13, where WITH TIES was introduced
Author: David Christensen <david.christensen@crunchydata.com>
Discussion: https://postgr.es/m/CAOxo6XLPccCKru3xPMaYDpa+AXyPeWFs+SskrrL+HKwDjJnLhg@mail.gmail.com

Commit ff9f111bce24 added some test code that's unportable and doesn't
add meaningful coverage.  Remove it rather than try and get it to work
everywhere.

While at it, fix a typo in a log message added by the aforementioned
commit.

Backpatch to 14.

Discussion: https://postgr.es/m/3000074.1632947632@sss.pgh.pa.us

The intermittent h buffer was not freed, causing it to leak. Backpatch
through 14 where HMAC was refactored to the current API.

Author: Sergey Shinderuk <s.shinderuk@postgrespro.ru>
Discussion: https://postgr.es/m/af07e620-7e28-a742-4637-2bc44aa7c2be@postgrespro.ru
Backpatch-through: 14

get_variable_range() would incautiously believe that statistics
containing only an MCV list are sufficient to derive a range estimate.
That's okay for an enum-like column that contains only MCVs, but
otherwise the estimate could be pretty bad.  Make it report that the
range is indeterminate unless the MCVs plus nullfrac account for
the whole table.

I don't think this needs a dedicated test case, since a quick code
coverage check verifies that the existing regression tests traverse
all the alternatives.  There is room to doubt that a future-proof
test case could be built anyway, given that the submitted example
accidentally doesn't fail before v11.

Per bug #17207 from Simon Perepelitsa.  Back-patch to v10.
In principle this has been broken all along, but I'm hesitant to
make such changes in 9.6, since if anyone is unhappy with 9.6.24's
behavior there will be no second chance to fix it.

Discussion: https://postgr.es/m/17207-5265aefa79e333b4@postgresql.org

Commit 84f5c290 forgot to consider the possibility that
EnsurePortalSnapshotExists could run inside a subtransaction with
lifespan shorter than the Portal's.  In that case, the new active
snapshot would be popped at the end of the subtransaction, leaving
a dangling pointer in the Portal, with mayhem ensuing.

To fix, make sure the ActiveSnapshot stack entry is marked with
the same subtransaction nesting level as the associated Portal.
It's certainly safe to do so since we won't be here at all unless
the stack is empty; hence we can't create an out-of-order stack.

Let's also apply this logic in the case where PortalRunUtility
sets portalSnapshot, just to be sure that path can't cause similar
problems.  It's slightly less clear that that path can't create
an out-of-order stack, so add an assertion guarding it.

Report and patch by Bertrand Drouvot (with kibitzing by me).
Back-patch to v11, like the previous commit.

Discussion: https://postgr.es/m/ff82b8c5-77f4-3fe7-6028-fcf3303e82dd@amazon.com

Commit 98681675 added pg_stat_replication_slots view to monitor
ReorderBuffer stats but mistakenly added it under
"Dynamic Statistics Views" section in the docs whereas it belongs to
"Collected Statistics Views" section.

Author: Amit Kapila
Reviewed-by: Masahiko Sawada
Backpatch-through: 14, where it was introduced
Discussion: https://postgr.es/m/CAA4eK1Kb5ur=OC-G4cAsqPOjoVe+S8LNw1WmUY8Owasjk8o5WQ@mail.gmail.com

Computing related timestamps by subtracting "N days" is sensitive
to the prevailing timezone, since we interpret that as "same local
time on the N'th prior day".  Even though the intervals in question
are only two to four days, through remarkable bad luck they managed
to cross the end of Ramadan in 2014, causing the test's output to
change if timezone is set to Africa/Casablanca.  (Maybe in other
Muslim areas as well; I didn't check.)  There's absolutely no reason
for this test to exercise interval subtraction, so just get rid of
that and use plain timestamptz constants representing the intended
values.

Per report from Andres Freund.  Back-patch to v10 where this test
script came in.

Discussion: https://postgr.es/m/20210930183641.7lh4jhvpipvromca@alap3.anarazel.de

First, as pointed out by Tom Lane and Michael Paquier, I failed to
realize that Windows' PostgresNode needs an extra pg_hba.conf line
(added by PostgresNode->set_replication_conf, called internally by
->init() when 'allows_streaming=>1' is given -- but I purposefully
omitted that).  I think a good fix should be to have nodes with only
'has_archiving=>1' set up for replication too, but that's a bigger
discussion.  Fix it by calling ->set_replication_conf, which is not
unprecedented, as pointed out by Andrew Dunstan.

I also forgot to uncomment a ->finish() call for a pumpable IPC::Run
file descriptor.  Apparently this is innocuous in almost all platforms.

Backpatch to 14.  The older branches were added this file too, but not
this particular part of the test.

Discussion: https://postgr.es/m/3000074.1632947632@sss.pgh.pa.us
Discussion: https://postgr.es/m/YVT7qwhR8JmC2kfz@paquier.xyz