Commit 4b82664156 restricted a number of functions provided by
contrib modules to only relations that use the "heap" table access
method. Sequences always use this table access method, but they do
not advertise as such in the pg_class system catalog, so the
aforementioned commit also (presumably unintentionally) removed
support for sequences from some of these functions. This commit
reintroduces said support for sequences to these functions and adds
a couple of relevant tests.
Co-authored-by: Ayush Vatsa
Reviewed-by: Robert Haas, Michael Paquier, Matthias van de Meent
Discussion: https://postgr.es/m/CACX%2BKaP3i%2Bi9tdPLjF5JCHVv93xobEdcd_eB%2B638VDvZ3i%3DcQA%40mail.gmail.com
Backpatch-through: 12
check_agglevels_and_constraints() asserted that if we find an
aggregate function in an EXPR_KIND_FROM_SUBSELECT expression, the
expression must be in a LATERAL subquery. Alexander Lakhin found a
case where that's not so: because of the odd scoping rules for NEW/OLD
within a rule, a reference to NEW/OLD could cause an aggregate to be
considered top-level even though it's in an unmarked sub-select.
The error message that would be thrown seems sufficiently on-point,
so just remove the Assert. (Hence, this is not a bug for production
builds.)
This Assert was added by me in commit eaccfded9 (9.3 era). It looks
like I put it in to cross-check that the new logic for detecting
misplaced aggregates (using agglevelsup) caught the same cases that a
previous check on p_lateral_active did. So there might have been some
related misbehavior before eaccfded9 ... but that's very ancient
history by now, so I didn't dig any deeper.
Per bug #18608 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18608-48de0717508ee429@postgresql.org
The first test was sensitive to the insert LSN after setting up the
catalogs, which depended on environmental things like the locales on the
OS and usernames. Switch to a new WAL file before the first test, as a
simple way to put every computer into the same state.
Back-patch to all supported releases.
Reported-by: Anton Voloshin <a.voloshin@postgrespro.ru>
Reported-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/b26aeac2-cb6d-4633-a7ea-945baae83dcf%40postgrespro.ru
This change improves the description of the
restrict_nonsystem_relation_kind parameter in guc_table.c and the
documentation for better clarity.
Backpatch to 12, where this GUC parameter was introduced.
Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/6a96f1af-22b4-4a80-8161-1f26606b9ee2%40eisentraut.org
Backpatch-through: 12
This does not make sense. It would write the output of the USING
clause into the converted column, which would violate the generation
expression. This adds a check to error out if this is specified.
There was a test for this, but that test errored out for a different
reason, so it was not effective.
Reported-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Yugo NAGATA <nagata@sraoss.co.jp>
Discussion: https://www.postgresql.org/message-id/flat/c7083982-69f4-4b14-8315-f9ddb20b9834%40eisentraut.org
The descriptions for ProcArrayGroupUpdate and XactGroupUpdate claim
that these events mean we are waiting for the group leader "at end
of a parallel operation," but neither pertains to parallel
operations. This commit reverts these descriptions to their
wording before commit 3048898e73, i.e., "end of a parallel
operation" is changed to "transaction end."
Author: Sameer Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAGPeHmh6UMrKQHKCmX%2B5vV5TH9P%3DKw9en3k68qEem6J%3DyrZPUA%40mail.gmail.com
Backpatch-through: 13
Add a comment explaining dropdb() can't rely on syscache. The issue with
flattened rows was fixed by commit 0f92b230f8, but better to have
a clear explanation why the systable scan is necessary. The other places
doing in-place updates on pg_database have the same comment.
Suggestion and patch by Yugo Nagata. Backpatch to 12, same as the fix.
Author: Yugo Nagata
Backpatch-through: 12
Discussion: https://postgr.es/m/CAJTYsWWNkCt+-UnMhg=BiCD3Mh8c2JdHLofPxsW3m2dkDFw8RA@mail.gmail.com
Commit 274bbced disabled session tickets for TLSv1.3 on top of the
already disabled TLSv1.2 session tickets, but accidentally caused
a regression where TLSv1.2 session tickets were incorrectly sent.
Fix by unconditionally disabling TLSv1.2 session tickets and only
disable TLSv1.3 tickets when the right version of OpenSSL is used.
Backpatch to all supported branches.
Reported-by: Cameron Vogt <cvogt@automaticcontrols.net>
Reported-by: Fire Emerald <fire.github@gmail.com>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://postgr.es/m/DM6PR16MB3145CF62857226F350C710D1AB852@DM6PR16MB3145.namprd16.prod.outlook.com
Backpatch-through: v12
Commit c66a7d75e6 modified DROP DATABASE so that if interrupted, the
database is known to be in an invalid state and can only be dropped.
This is done by setting a flag using an in-place update, so that it's
not lost in case of rollback.
For databases with many ACLs, this may however fail like this:
ERROR: wrong tuple length
This happens because with many ACLs, the pg_database.datacl attribute
gets TOASTed. The dropdb() code reads the tuple from the syscache, which
means it's detoasted. But the in-place update expects the tuple length
to match the on-disk tuple.
Fixed by reading the tuple from the catalog directly, not from syscache.
Report and fix by Ayush Tiwari. Backpatch to 12. The DROP DATABASE fix
was backpatched to 11, but 11 is EOL at this point.
Reported-by: Ayush Tiwari
Author: Ayush Tiwari
Reviewed-by: Tomas Vondra
Backpatch-through: 12
Discussion: https://postgr.es/m/CAJTYsWWNkCt+-UnMhg=BiCD3Mh8c2JdHLofPxsW3m2dkDFw8RA@mail.gmail.com
If a partition undergoes DETACH CONCURRENTLY immediately followed by
DROP, this could cause a problem for a concurrent transaction
recomputing the partition descriptor when running a prepared statement,
because it tries to dereference a pointer to a tuple that's not found in
a catalog scan.
The existing retry logic added in commit dbca3469eb is sufficient to
cope with the overall problem, provided we don't try to dereference a
non-existant heap tuple.
Arguably, the code in RelationBuildPartitionDesc() has been wrong all
along, since no check was added in commit 898e5e3290 against receiving
a NULL tuple from the catalog scan; that bug has only become
user-visible with DETACH CONCURRENTLY which was added in branch 14.
Therefore, even though there's no known mechanism to cause a crash
because of this, backpatch the addition of such a check to all supported
branches. In branches prior to 14, this would cause the code to fail
with a "missing relpartbound for relation XYZ" error instead of
crashing; that's okay, because there are no reports of such behavior
anyway.
Author: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/18559-b48286d2eacd9a4e@postgresql.org
Coverity thinks dpns->plan could be null at these points. That
shouldn't really be possible, but it's easy enough to modify the
Asserts so they'd not core-dump if it were true.
These are new in b919a97a6. Back-patch to v13; the v12 version
of the patch didn't have these Asserts.
The code intends to allow GUCs to be set within parallel workers
via function SET clauses, but not otherwise. However, doing so fails
for "session_authorization" and "role", because the assign hooks for
those attempt to set the subsidiary "is_superuser" GUC, and that call
falls foul of the "not otherwise" prohibition. We can't switch to
using GUC_ACTION_SAVE for this, so instead add a new GUC variable
flag GUC_ALLOW_IN_PARALLEL to mark is_superuser as being safe to set
anyway. (This is okay because is_superuser has context PGC_INTERNAL
and thus only hard-wired calls can change it. We'd need more thought
before applying the flag to other GUCs; but maybe there are other
use-cases.) This isn't the prettiest fix perhaps, but other
alternatives we thought of would be much more invasive.
While here, correct a thinko in commit 059de3ca4: when rejecting
a GUC setting within a parallel worker, we should return 0 not -1
if the ereport doesn't longjmp. (This seems to have no consequences
right now because no caller cares, but it's inconsistent.) Improve
the comments to try to forestall future confusion of the same kind.
Despite the lack of field complaints, this seems worth back-patching.
Thanks to Nathan Bossart for the idea to invent a new flag,
and for review.
Discussion: https://postgr.es/m/2833457.1723229039@sss.pgh.pa.us
This section claims we use CRC-32 for WAL records and two-phase
state files, but we've actually used CRC-32C since v9.5 (commit
5028f22f6e). Fix that.
Reviewed-by: Robert Haas
Discussion: https://postgr.es/m/ZrUFpLP-w2zTAHqq%40nathan
Backpatch-through: 12
To deparse a reference to a field of a RECORD-type output of a
subquery, EXPLAIN normally digs down into the subquery's plan to try
to discover exactly which anonymous RECORD type is meant. However,
this can fail if the subquery has been optimized out of the plan
altogether on the grounds that no rows could pass the WHERE quals,
which has been possible at least since 3fc6e2d7f. There isn't
anything remaining in the plan tree that would help us, so fall back
to printing the field name as "fN" for the N'th column of the record.
(This will actually be the right thing some of the time, since it
matches the column names we assign to RowExprs.)
In passing, fix a comment typo in create_projection_plan, which
I noticed while experimenting with an alternative fix for this.
Per bug #18576 from Vasya B. Back-patch to all supported branches.
Richard Guo and Tom Lane
Discussion: https://postgr.es/m/18576-9feac34e132fea9e@postgresql.org
Trying to attach a table as a partition which is already on the
referenced side of a foreign key on the partitioned table that it is
being attached to, leads to strange behavior: we try to clone the
foreign key from the parent to the partition, but this new FK points to
the partition itself, and the mix of pg_constraint rows and triggers
doesn't behave well.
Rather than trying to untangle the mess (which might be possible given
sufficient time), I opted to forbid the ATTACH. This doesn't seem a
problematic restriction, given that we already fail to create the
foreign key if you do it the other way around, that is, having the
partition first and the FK second.
Backpatch to all supported branches.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/18541-628a61bc267cd2d3@postgresql.org
getTimelineHistory() is called twice, to read the source and the
target timeline history files. However, the loop to print the file
with the --debug option used the wrong variable when dealing with the
source. As a result, the source's history was always printed as empty.
Spotted while debugging bug #18575, but this does not fix that bug,
just the debugging output. Backpatch to all supported versions.
Discussion: https://www.postgresql.org/message-id/092dd515-b7b4-4fd0-8407-ceca2f02f6ec@iki.fi
Commit 0b9466fce added a dependency on fe_memutils' pnstrdup() inside
informix.c. This adds an exit() path in a library, which we don't
want. (Unlike libpq, the ecpg libraries don't have an automated check
for that, but it makes sense to keep them to a similar standard.) The
ecpg code can already handle failure results from the *strdup() call
by itself.
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/CAOYmi+=pg=W5L1h=3MEP_EB24jaBu2FyATrLXqQHGe7cpuvwyg@mail.gmail.com
When commit 1185be3554 introduced
installation of a file containing "use PostgreSQL::Test::Utils", the RPM
Package Manager said "nothing provides perl(PostgreSQL::Test::Utils)".
Discussed on pgsql-packagers. Back-patch to v12, v13, and v14 only;
newer versions don't have the alias packages.
Reviewed by Andrew Dunstan, Tom Lane, and John Harvey. Reported by John
Harvey.
When pg_dump retrieves the list of database objects and performs the
data dump, there was possibility that objects are replaced with others
of the same name, such as views, and access them. This vulnerability
could result in code execution with superuser privileges during the
pg_dump process.
This issue can arise when dumping data of sequences, foreign
tables (only 13 or later), or tables registered with a WHERE clause in
the extension configuration table.
To address this, pg_dump now utilizes the newly introduced
restrict_nonsystem_relation_kind GUC parameter to restrict the
accesses to non-system views and foreign tables during the dump
process. This new GUC parameter is added to back branches too, but
these changes do not require cluster recreation.
Back-patch to all supported branches.
Reviewed-by: Noah Misch
Security: CVE-2024-7348
Backpatch-through: 12
This reverts commit 216201027d.
Some buildfarm animals are failing with "cannot change
"client_encoding" during a parallel operation". It looks like
assign_client_encoding is unhappy at being asked to roll back a
client_encoding setting after a parallel worker encounters a
failure. There must be more to it though: why didn't I see this
during local testing? In any case, it's clear that moving the
RestoreGUCState() call is not as side-effect-free as I thought.
Given that the bug f5f30c22e intended to fix has gone unreported
for years, it's not something that's urgent to fix; I'm not
willing to risk messing with it further with only days to our
next release wrap.
Parallel workers failed after a sequence like
BEGIN;
CREATE USER foo;
SET SESSION AUTHORIZATION foo;
because check_session_authorization could not see the uncommitted
pg_authid row for "foo". This is because we ran RestoreGUCState()
in a separate transaction using an ordinary just-created snapshot.
The same disease afflicts any other GUC that requires catalog lookups
and isn't forgiving about the lookups failing.
To fix, postpone RestoreGUCState() into the worker's main transaction
after we've set up a snapshot duplicating the leader's. This affects
check_transaction_isolation and check_transaction_deferrable, which
think they should only run during transaction start. Make them
act like check_transaction_read_only, which already knows it should
silently accept the value when InitializingParallelWorker.
Per bug #18545 from Andrey Rachitskiy. Back-patch to all
supported branches, because this has been wrong for awhile.
Discussion: https://postgr.es/m/18545-feba138862f19aaa@postgresql.org
Prior to this commit, the docs for enable_partitionwise_aggregate and
enable_partitionwise_join mentioned the additional overheads enabling
these causes for the query planner, but they mentioned nothing about the
possible surge in work_mem-consuming executor nodes that could end up in
the final plan. Dimitrios reported the OOM killer intervened on his
query as a result of using enable_partitionwise_aggregate=on.
Here we adjust the docs to mention the possible increase in the number of
work_mem-consuming executor nodes that can appear in the final plan as a
result of enabling these GUCs.
Reported-by: Dimitrios Apostolou
Reviewed-by: Ashutosh Bapat
Discussion: https://postgr.es/m/3603c380-d094-136e-e333-610914fb3e80%40gmx.net
Discussion: https://postgr.es/m/CAApHDvoZ0_yqwPFEpb6h261L76BUpmh5GxBQq0LeRzQ5Jh3zzg@mail.gmail.com
Backpatch-through: 12, oldest supported version
Commit 453c468737 introduced a use of strerror() into libpq, but that
is not thread-safe. Fix by using strerror_r() instead.
In passing, update some of the code comments added by 453c468737, as
we have learned more about the reason for the change in OpenSSL that
started this.
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: Discussion: https://postgr.es/m/b6fb018b-f05c-4afd-abd3-318c649faf18@highgo.ca
Commit 274bbced85 accidentally placed the pg_config.h.in
for SSL_CTX_set_num_tickets on the wrong line wrt where autoheader
places it. Fix by re-arranging and backpatch to the same level as
the original commit.
Reported-by: Marina Polyakova <m.polyakova@postgrespro.ru>
Discussion: https://postgr.es/m/48cebe8c3eaf308bae253b1dbf4e4a75@postgrespro.ru
Backpatch-through: v12
OpenSSL supports two types of session tickets for TLSv1.3, stateless
and stateful. The option we've used only turns off stateless tickets
leaving stateful tickets active. Use the new API introduced in 1.1.1
to disable all types of tickets.
Backpatch to all supported versions.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20240617173803.6alnafnxpiqvlh3g@awork3.anarazel.de
Backpatch-through: v12
We don't allow inheritance parents as partitions, and have checks to
prevent this; but if a table _was_ in the past an inheritance parents
and all their children are removed, the pg_class.relhassubclass flag
may remain set, which confuses the partition pruning code (most
obviously, it results in an assertion failure; in production builds it
may be worse.)
Fix by resetting relhassubclass on attach.
Backpatch to all supported versions.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18550-d5e047e9a897a889@postgresql.org
When provided an empty initial array, array_set_slice() fails to
check for overflow when computing the new array's dimensions.
While such overflows are ordinarily caught by ArrayGetNItems(),
commands with the following form are accepted:
INSERT INTO t (i[-2147483648:2147483647]) VALUES ('{}');
To fix, perform the hazardous computations using overflow-detecting
arithmetic routines. As with commit 18b585155a, the added test
cases generate errors that include a platform-dependent value, so
we again use psql's VERBOSITY parameter to suppress printing the
message text.
Reported-by: Alexander Lakhin
Author: Joseph Koshakow
Reviewed-by: Jian He
Discussion: https://postgr.es/m/31ad2cd1-db94-bdb3-f91a-65ffdb4bef95%40gmail.com
Backpatch-through: 12
We were not being clear about which variants of the "direction"
clause are permitted in MOVE. Also, the text seemed to be
written with only the FETCH/MOVE NEXT case in mind, so it
didn't apply very well to other variants.
Also, document that "MOVE count IN cursor" only works if count
is a constant. This is not the whole truth, because some other
cases such as a parenthesized expression will also work, but
we want to push people to use "MOVE FORWARD count" instead.
The constant case is enough to cover what we allow in plain SQL,
and that seems sufficient to claim support for.
Update a comment in pl_gram.y claiming that we don't document
that point.
Per gripe from Philipp Salvisberg.
Discussion: https://postgr.es/m/172155553388.702.7932496598218792085@wrigleys.postgresql.org
If a view has some updatable and some non-updatable columns, we failed
to verify updatability of any columns for which an INSERT or UPDATE
on the view explicitly specifies a DEFAULT item (unless the view has
a declared default for that column, which is rare anyway, and one
would almost certainly not write one for a non-updatable column).
This would lead to an unexpected "attribute number N not found in
view targetlist" error rather than the intended error.
Per bug #18546 from Alexander Lakhin. This bug is old, so back-patch
to all supported branches.
Discussion: https://postgr.es/m/18546-84a292e759a9361d@postgresql.org
Before this change guc_var_compare() cast the input arguments to
const struct config_generic *. That's not quite right however, as the input
on one side is often just a char * on one side.
Instead just use char *, the first field in config_generic.
This fixes a -Warray-bounds warning with some versions of gcc. While the
warning is only known to be triggered for <= 15, the issue the warning points
out seems real, so apply the fix everywhere.
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reported-by: Erik Rijkers <er@xs4all.nl>
Suggested-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/a74a1a0d-0fd2-3649-5224-4f754e8f91aa%40xs4all.nl
checkWellFormedRecursion would issue "missing recursive reference"
if a WITH RECURSIVE query contained a single self-reference but
that self-reference was inside a top-level WITH, ORDER BY, LIMIT,
etc, rather than inside the second arm of the UNION as expected.
We already intended to throw more-on-point errors for such cases,
but those error checks must be done before examining the UNION arm
in order to have the desired results. So this patch need only
move some code (and improve the comments).
Per bug #18536 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18536-0a342ec07901203e@postgresql.org
The current code can have pg_isready unexpectedly succeed if there is a
server running on the default port. To avoid this we delay running the
test until after a node has been created but before it starts, and then
use that node's port, so we are fairly sure there is nothing running on
the port.
Backpatch to all live branches.
Winsock only signals an FD_CLOSE event once if the other end of the
socket shuts down gracefully. Because each WaitLatchOrSocket() call
constructs and destroys a new event handle every time, with unlucky
timing we can lose it and hang. We get away with this only if the other
end disconnects non-gracefully, because FD_CLOSE is repeatedly signaled
in that case.
To fix this design flaw in our Windows socket support fundamentally,
we'd probably need to rearchitect it so that a single event handle
exists for the lifetime of a socket, or switch to completely different
multiplexing or async I/O APIs. That's going to be a bigger job
and probably wouldn't be back-patchable.
This brute force kludge closes the race by explicitly polling with
MSG_PEEK before sleeping.
Back-patch to all supported releases. This should hopefully clear up
some random build farm and CI hang failures reported over the years. It
might also allow us to try using graceful shutdown in more places again
(reverted in commit 29992a6) to fix instability in the transmission of
FATAL error messages, but that isn't done by this commit.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Tested-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/176008.1715492071%40sss.pgh.pa.us
When a partitioned table has an index that doesn't support a constraint,
but a partition has an equivalent index that does, then a DETACH
operation would misbehave: a crash in assertion-enabled systems (because
we fail to find the constraint in the parent that we expect to), or a
broken coninhcount value (-1) in production systems (because we blindly
believe that we've successfully detached the parent).
While we should reject an ATTACH of a partition with such an index, we
have failed to do so in existing releases, so adding an error in stable
releases might break the (unlikely) existing applications that rely on
this behavior. At this point I don't even want to reject them in
master, because it'd break pg_upgrade if such databases exist, and there
would be no easy way to fix existing databases without expensive index
rebuilds.
(Later on we could add ALTER TABLE ... ADD CONSTRAINT USING INDEX to
partitioned tables, which would allow the user to fix such patterns. At
that point we could add more restrictions to prevent the problem from
its root.)
Also, add a test case that leaves one table in this condition, so that
we can verify that pg_upgrade continues to work if we later decide to
change the policy on the master branch.
Backpatch to all supported branches.
Co-authored-by: Tender Wang <tndrwang@gmail.com>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18500-62948b6fe5522f56@postgresql.org
When creating and initializing a logical slot, the restart_lsn is set
to the latest WAL insertion point (or the latest replay point on
standbys). Subsequently, WAL records are decoded from that point to
find the start point for extracting changes in the
DecodingContextFindStartpoint() function. Since the initial
restart_lsn could be in the middle of a transaction, the start point
must be a consistent point where we won't see the data for partial
transactions.
Previously, when not building a full snapshot, serialized snapshots
were restored, and the SnapBuild jumps to the consistent state even
while finding the start point. Consequently, the slot's restart_lsn
and confirmed_flush could be set to the middle of a transaction. This
could lead to various unexpected consequences. Specifically, there
were reports of logical decoding decoding partial transactions, and
assertion failures occurred because only subtransactions were decoded
without decoding their top-level transaction until decoding the commit
record.
To resolve this issue, the changes prevent restoring the serialized
snapshot and jumping to the consistent state while finding the start
point.
On v17 and HEAD, a flag indicating whether snapshot restores should be
skipped has been added to the SnapBuild struct, and SNAPBUILD_VERSION
has been bumpded.
On backbranches, the flag is stored in the LogicalDecodingContext
instead, preserving on-disk compatibility.
Backpatch to all supported versions.
Reported-by: Drew Callahan
Reviewed-by: Amit Kapila, Hayato Kuroda
Discussion: https://postgr.es/m/2444AA15-D21B-4CCE-8052-52C7C2DAFE5C%40amazon.com
Backpatch-through: 12
This back-patches HEAD commits 066e8ac6e, 6082b3d5d, e7192486d,
and 896cd266f into supported branches. Changes:
* Use xmlAddChildList not xmlAddChild in XMLSERIALIZE
(affects v16 and up only). This was a flat-out coding mistake
that we got away with due to lax checking in previous versions
of xmlAddChild.
* Use xmlParseInNodeContext not xmlParseBalancedChunkMemory.
This is to dodge a bug in xmlParseBalancedChunkMemory in libxm2
releases 2.13.0-2.13.2. While that bug is now fixed upstream and
will probably never be seen in any production-oriented distro, it is
currently a problem on some more-bleeding-edge-friendly platforms.
* Suppress "chunk is not well balanced" errors from libxml2,
unless it is the only error. This eliminates an error-reporting
discrepancy between 2.13 and older releases. This error is
almost always redundant with previous errors, if not flat-out
inappropriate, which is why 2.13 changed the behavior and why
nobody's likely to miss it.
Erik Wienhold and Tom Lane, per report from Frank Streitzig.
Discussion: https://postgr.es/m/trinity-b0161630-d230-4598-9ebc-7a23acdb37cb-1720186432160@3c-app-gmx-bap25
Discussion: https://postgr.es/m/trinity-361ba18b-541a-4fe7-bc63-655ae3a7d599-1720259822452@3c-app-gmx-bs01
Nathan Bossart