If temp tables have dependencies (such as sequences) then it's
possible for autovacuum's cleanup of orphan temp tables to deadlock
against an incoming backend that's trying to clean out the temp
namespace for its own use. That can happen because RemoveTempRelations'
performDeletion call can visit objects within the namespace in
an order different from the order in which a per-table deletion
will visit them.
To fix, observe that performDeletion will begin by taking an exclusive
lock on the temp namespace (even though it won't actually delete it).
So, if we can get a shared lock on the namespace, we can be sure we're
not running concurrently with RemoveTempRelations, while also not
conflicting with ordinary use of the namespace. This requires
introducing a conditional version of LockDatabaseObject, but that's no
big deal. (It's surprising we've got along without that this long.)
Report and patch by Mikhail Zhilin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/c43ce028-2bc2-4865-9b89-3f706246eed5@postgrespro.ru
If we are building with openssl but USE_SSL_ENGINE didn't get set,
initialize_SSL's variable "pkey" is declared but used nowhere.
Apparently this combination hasn't been exercised in the buildfarm
before now, because I've not seen this warning before, even though
the code has been like this a long time. Move the declaration
to silence the warning (and remove its useless initialization).
Per buildfarm member sawshark. Back-patch to all supported branches.
The "pltargs" variable wasn't marked volatile, which makes it unsafe
to change its value within the PG_TRY block. It looks like the worst
outcome would be to fail to release a refcount on Py_None during an
(improbable) error exit, which would likely go unnoticed in the field.
Still, it's a bug. A one-liner fix could be to mark pltargs volatile,
but on the whole it seems cleaner to arrange things so that we don't
change its value within PG_TRY.
Per report from Xing Guo. This has been there for quite awhile,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/CACpMh+DLrk=fDv07MNpBT4J413fDAm+gmMXgi8cjPONE+jvzuw@mail.gmail.com
When a plain aggregate is used as a window function, and the window
frame start is specified as UNBOUNDED PRECEDING, the frame's head
cannot move so we do not need to use moving-aggregate mode. The check
for that was put into initialize_peragg(), failing to notice that
ExecInitWindowAgg() calls that function before it's filled in
winstate->frameOptions. Since makeNode() would have zeroed the field,
this didn't provoke uninitialized-value complaints, nor would the
erroneous decision have resulted in more than a little inefficiency.
Still, it's wrong, so move the initialization of
winstate->frameOptions earlier to make it work properly.
While here, also fix a thinko in a comment. Both errors crept in in
commit a9d9acbf2 which introduced the moving-aggregate mode.
Spotted by Vallimaharajan G. Back-patch to all supported branches.
Discussion: https://postgr.es/m/18e7f2a5167.fe36253866818.977923893562469143@zohocorp.com
Ordinary ALTER TABLE SET SCHEMA will also move any owned sequences
into the new schema. We failed to do likewise for foreign tables,
because AlterTableNamespaceInternal believed that only certain
relkinds could have indexes, owned sequences, or constraints.
We could simply add foreign tables to that relkind list, but it
seems likely that the same oversight could be made again in
future. Instead let's remove the relkind filter altogether.
These functions shouldn't cost much when there are no objects
that they need to process, and surely this isn't an especially
performance-critical case anyway.
Per bug #18407 from Vidushi Gupta. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18407-4fd07373d252c6a0@postgresql.org
The musl dynamic linker saves a pointer to the process' environment
value of LD_LIBRARY_PATH very early in startup. When we move/clobber
the environment to make more room for ps status strings, we clobber
that value and thereby prevent libraries from being found via
LD_LIBRARY_PATH, which breaks the use of a temporary installation
for testing purposes. To fix, stop collecting usable space for
ps status if we notice that the variable we are about to clobber
is LD_LIBRARY_PATH. This will result in some reduction in how long
the ps status can be, but it's only likely to occur in temporary
test contexts, so it doesn't seem like a big problem. In any case,
we don't have to do it if we see we are on glibc, which surely is
where the majority of our Linux testing is done.
Thomas Munro, Bruce Momjian, and Tom Lane, per report from Wolfgang
Walther. Back-patch to all supported branches, with the hope that
we'll set up a buildfarm animal to test on this platform.
Discussion: https://postgr.es/m/fddd1cd6-dc16-40a2-9eb5-d7fef2101488@technowledgy.de
It might happen that the varlena value wasn't compressed by index_form_tuple()
due to current storage parameters. If compression is currently enabled, we
need to compress such values to match index tuple coming from the heap.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/flat/7bdbe559-d61a-4ae4-a6e1-48abdf3024cc%40postgrespro.ru
Author: Andrey Borodin
Reviewed-by: Alexander Lakhin, Michael Zhilin, Jian He, Alexander Korotkov
Backpatch-through: 12
In the heap, tuples may contain short varlena datum with both 1B header and 4B
headers. But the corresponding index tuple should always have such varlena's
with 1B headers. So, for fingerprinting, we need to convert.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/flat/7bdbe559-d61a-4ae4-a6e1-48abdf3024cc%40postgrespro.ru
Author: Michael Zhilin
Reviewed-by: Alexander Lakhin, Andrey Borodin, Jian He, Alexander Korotkov
Backpatch-through: 12
Already removed incidentally in version 15 (c4649cce3), so this commit
is only applied to versions 13 and 14.
The comment above is misleading in all versions 13 and later, so that
will be fixed in a separate commit.
Discussion: https://postgr.es/m/cfd84cb8-12fe-433a-a4bb-f460a4515f9c.zhaotinghai.zth%40alibaba-inc.com
Reported-by: Tinghai Zhao
Backpatch-through: 13
Some last minute polish of the patch managed to break the SQL
query for extracting the role comments due to fat-fingering.
Per the buildfarm Xversion tests.
Commit a3c7a993d fixed some cases involving target columns that are
arrays or composites by applying transformAssignedExpr to the VALUES
entries, and then stripping off any assignment ArrayRefs or
FieldStores that the transformation added. But I forgot about domains
over arrays or composites :-(. Such cases would either fail with
surprising complaints about mismatched datatypes, or insert unexpected
coercions that could lead to odd results. To fix, extend the
stripping logic to get rid of CoerceToDomain if it's atop an ArrayRef
or FieldStore.
While poking at this, I realized that there's a poorly documented and
not-at-all-tested behavior nearby: we coerce each VALUES column to
the domain type separately, and rely on the rewriter to merge those
operations so that the domain constraints are checked only once.
If that merging did not happen, it's entirely possible that we'd get
unexpected domain constraint failures due to checking a
partially-updated container value. There's no bug there, but while
we're here let's improve the commentary about it and add some test
cases that explicitly exercise that behavior.
Per bug #18393 from Pablo Kharo. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18393-65fedb1a0de9260d@postgresql.org
There is a very ancient hack in check_sql_fn_retval that allows a
single SELECT targetlist entry of composite type to be taken as
supplying all the output columns of a function returning composite.
(This is grotty and fundamentally ambiguous, but it's really hard
to do nested composite-returning functions without it.)
As far as I know, that doesn't cause any problems in ordinary
functions. It's disastrous for procedures however. All procedures
that have any output parameters are labeled with prorettype RECORD,
and the CALL code expects it will get back a record with one column
per output parameter, regardless of whether any of those parameters
is composite. Doing something else leads to an assertion failure
or core dump.
This is simple enough to fix: we just need to not apply that rule
when considering procedures. However, that requires adding another
argument to check_sql_fn_retval, which at least in principle might be
getting called by external callers. Therefore, in the back branches
convert check_sql_fn_retval into an ABI-preserving wrapper around a
new function check_sql_fn_retval_ext.
Per report from Yahor Yuzefovich. This has been broken since we
implemented procedures, so back-patch to all supported branches.
Discussion: https://postgr.es/m/CABz5gWHSjj2df6uG0NRiDhZ_Uz=Y8t0FJP-_SVSsRsnrQT76Gg@mail.gmail.com
Commit 387da18874 moved the code to put socket into non-blocking mode
from socket_set_nonblocking() into the one-time initialization
function, pq_init(). In socket_set_nonblocking(), there indeed was a
risk of recursion on failure like the comment said, but in pq_init(),
ERROR or FATAL is fine. There's even another elog(FATAL) just after
this, if setting FD_CLOEXEC fails.
Note that COMMERROR merely logged the error, it did not close the
connection, so if putting the socket to non-blocking mode failed we
would use the connection anyway. You might not immediately notice,
because most socket operations in a regular backend wait for the
socket to become readable/writable anyway. But e.g. replication will
be quite broken.
Backpatch to all supported versions.
Discussion: https://www.postgresql.org/message-id/d40a5cd0-2722-40c5-8755-12e9e811fa3c@iki.fi
For pass-by-reference types, the code added in 0b053e78b, which aimed to
resolve a memory leak, was overly aggressive in resetting the per-tuple
memory context which could result in pfree'd memory being accessed
resulting in failing to find previously cached results in the hash
table.
What was happening was prepare_probe_slot() was switching to the
per-tuple memory context and calling ExecEvalExpr(). ExecEvalExpr() may
have required a memory allocation. Both MemoizeHash_hash() and
MemoizeHash_equal() were aggressively resetting the per-tuple context
and after determining the hash value, the context would have gotten reset
before MemoizeHash_equal() was called. This could have resulted in
MemoizeHash_equal() looking at pfree'd memory.
This is less likely to have caused issues on a production build as some
other allocation would have had to have reused the pfree'd memory to
overwrite it. Otherwise, the original contents would have been intact.
However, this clearly caused issues on MEMORY_CONTEXT_CHECKING builds.
Author: Tender Wang, Andrei Lepikhov
Reported-by: Tender Wang (using SQLancer)
Reviewed-by: Andrei Lepikhov, Richard Guo, David Rowley
Discussion: https://postgr.es/m/CAHewXNnT6N6UJkya0z-jLFzVxcwGfeRQSfhiwA+NyLg-x8iGew@mail.gmail.com
Backpatch-through: 14, where Memoize was added
For UNION ALL queries where a union child query contained a foreign
table, if the targetlist of that query contained a constant, and the
top-level query performed an ORDER BY which contained the column for the
constant value, then postgres_fdw would find the EquivalenceMember with
the Const and then try to produce an ORDER BY containing that Const.
This caused problems with INT typed Consts as these could appear to be
requests to order by an ordinal column position rather than the constant
value. This could lead to either an error such as:
ERROR: ORDER BY position <int const> is not in select list
or worse, if the constant value is a valid column, then we could just
sort by the wrong column altogether.
Here we fix this issue by just not including these Consts in the ORDER
BY clause.
In passing, add a new section for testing ORDER BY in the postgres_fdw
tests and move two existing tests which were misplaced in the WHERE
clause testing section into it.
Reported-by: Michał Kłeczek
Reviewed-by: Ashutosh Bapat, Richard Guo
Bug: #18381
Discussion: https://postgr.es/m/0714C8B8-8D82-4ABB-9F8D-A0C3657E7B6E%40kleczek.org
Discussion: https://postgr.es/m/18381-137456acd168bf93%40postgresql.org
Backpatch-through: 12, oldest supported version
In OpenSSL 3.0.0 and later, ERR_reason_error_string randomly refuses
to provide a string for error codes representing system errno values
(e.g., "No such file or directory"). There is a poorly-documented way
to extract the errno from the SSL error code in this case, so do that
and apply strerror, rather than falling back to reporting the error
code's numeric value as we were previously doing.
Problem reported by David Zhang, although this is not his proposed
patch; it's instead based on a suggestion from Heikki Linnakangas.
Back-patch to all supported branches, since any of them are likely
to be used with recent OpenSSL.
Discussion: https://postgr.es/m/b6fb018b-f05c-4afd-abd3-318c649faf18@highgo.ca
This reverts commit eae7be600be7, following a discussion with Tom Lane,
due to concerns that this impacts the decisions made by the planner for
the number of workers spawned based on the inlining and const-folding of
index expressions and predicate for cases that would have worked until
this commit.
Discussion: https://postgr.es/m/162802.1709746091@sss.pgh.pa.us
Backpatch-through: 12
In the corner case where a function returning RECORD has been
simplified to a RECORD constant or an inlined ROW() expression,
ExecInitFunctionScan failed to cross-check the function's result
rowtype against the coldeflist provided by the calling query.
That happened because get_expr_result_type is able to extract a
tupdesc from such expressions, which led ExecInitFunctionScan to
ignore the coldeflist. (Instead, it used the extracted tupdesc
to check the function's output, which of course always succeeds.)
I have not been able to demonstrate any really serious consequences
from this, because if some column of the result is of the wrong
type and is directly referenced by a Var of the calling query,
CheckVarSlotCompatibility will catch it. However, we definitely do
fail to report the case where the function returns more columns than
the coldeflist expects, and in the converse case where it returns
fewer columns, we get an assert failure (but, seemingly, no worse
results in non-assert builds).
To fix, always build the expected tupdesc from the coldeflist if there
is one, and consult get_expr_result_type only when there isn't one.
Also remove the failing Assert, even though it is no longer reached
after this fix. It doesn't seem to be adding anything useful, since
later checking will deal with cases with the wrong number of columns.
The only other place I could find that is doing something similar
is inline_set_returning_function. There's no live bug there because
we cannot be looking at a Const or RowExpr, but for consistency
change that code to agree with ExecInitFunctionScan.
Per report from PetSerAl. After some debate I've concluded that
this should be back-patched. There is a small risk that somebody
has been relying on such a case not throwing an error, but I judge
this outweighed by the risk that I've missed some way in which the
failure to cross-check has worse consequences than sketched above.
Discussion: https://postgr.es/m/CAKygsHSerA1eXsJHR9wft3Gn3wfHQ5RfP8XHBzF70_qcrrRvEg@mail.gmail.com
As coded, the planner logic that calculates the number of parallel
workers to use for a parallel index build uses expressions and
predicates from the relcache, which are flattened for the planner by
eval_const_expressions().
As reported in the bug, an immutable parallel-unsafe function flattened
in the relcache would become a Const, which would be considered as
parallel-safe, even if the predicate or the expressions including the
function are not safe in parallel workers. Depending on the expressions
or predicate used, this could cause the parallel build to fail.
Tests are included that check parallel index builds with parallel-unsafe
predicate and expressions. Two routines are added to lsyscache.h to be
able to retrieve expressions and predicate of an index from its pg_index
data.
Reported-by: Alexander Lakhin
Author: Tender Wang
Reviewed-by: Jian He, Michael Paquier
Discussion: https://postgr.es/m/CAHewXN=UaAaNn9ruHDH3Os8kxLVmtWqbssnf=dZN_s9=evHUFA@mail.gmail.com
Backpatch-through: 12
The error message(s) were reporting the stats kind of 'f', which is not
correct as that's for the "dependencies" statistics kind.
Reported-by: Horst Reiterer
Reviewed-by: Richard Guo
Discussion: https://postgr.es/m/18375-ba99383eb9062d6a@postgresql.org
Backpatch-through: 12, where MCV extended stats were added.
dsa_dump would print a large negative number instead of zero for
segment bin 0. Fix by explicitly checking for underflow and add
special case for bin 0. Backpatch to all supported versions.
Author: Ian Ilyasov <ianilyasov@outlook.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/GV1P251MB1004E0D09D117D3CECF9256ECD502@GV1P251MB1004.EURP251.PROD.OUTLOOK.COM
Backpatch-through: v12
In the case where the target timestamp is before the origin timestamp
and their difference is already an exact multiple of the stride, the
code incorrectly subtracted the stride anyway.
Also detect several integer-overflow cases that previously produced
bogus results. (The submitted patch tried to avoid overflow, but
I'm not convinced it's right, and problematic cases are so far out of
the plausibly-useful range that they don't seem worth sweating over.
Let's just use overflow-detecting arithmetic and throw errors.)
timestamp_bin() and timestamptz_bin() are basically identical and
so had identical bugs. Fix both.
Report and patch by Moaaz Assali, adjusted some by me. Back-patch
to v14 where date_bin() was introduced.
Discussion: https://postgr.es/m/CALkF+nvtuas-2kydG-WfofbRSJpyODAJWun==W-yO5j2R4meqA@mail.gmail.com
When this assertion was installed (in commit d2f60a3ab), I thought
it was only for catching server logic errors that caused accesses to
catalogs that were undergoing index rebuilds. However, it will also
fire in case of a user-defined index expression that attempts to
access its own table. We occasionally see reports of people trying
to do that, and typically getting unintelligible low-level errors
as a result. We can provide a more on-point message by making this
a regular runtime check.
While at it, adjust the similar error check in
systable_beginscan_ordered to use the same message text. That one
is (probably) not reachable without a coding bug, but we might as
well use a translatable message if we have one.
Per bug #18363 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18363-e3598a5a572d0699@postgresql.org
build_child_join_sjinfo creates a derived SpecialJoinInfo in
the short-lived GEQO context, but afterwards the semi_rhs_exprs
from that may be used in a UniquePath for a child base relation.
This breaks the expectation that all base-relation-level structures
are in the planning-lifespan context, leading to use of a dangling
pointer with probable ensuing crash later on in create_unique_plan.
To fix, copy the expression trees when making a UniquePath.
Per bug #18360 from Alexander Lakhin. This has been broken since
partitionwise joins were added, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/18360-a23caf3157f34e62@postgresql.org
The explanation of interval's behavior in datatype.sgml wasn't wrong
exactly, but it was unclear, partly because it buried the lede about
there being three internal fields. Rearrange and wordsmith for more
clarity.
The discussion of extract() claimed that input of type date was
handled by casting, but actually there's been a separate SQL function
taking date for a very long time. Also, it was mostly silent about
how interval inputs are handled, but there are several field types
for which it seems useful to be specific.
Improve discussion of justify_days()/justify_hours() too.
In passing, remove vertical space in some groups of examples,
as there was little consistency about whether to have such space
or not. (I only did this within the datetime functions section;
there are some related inconsistencies elsewhere.)
Per discussion of bug #18348 from Michael Bondarenko. There
may be some code changes coming out of that discussion too,
but we likely won't back-patch them. This docs-only patch
seems useful to back-patch, though I only carried it back to
v13 because it didn't apply easily in v12.
Discussion: https://postgr.es/m/18348-b097a3587dfde8a4@postgresql.org
Commits 1b2c6b756 et al affected the core BRIN "bloom" opclasses,
not contrib/bloom. This only corrected a bad assertion so it's not
too significant to end users, but since we documented it we should
do so accurately.
Spotted by Takatsuka Haruka.
Discussion: https://postgr.es/m/18353-926aa99cfe58aa78@postgresql.org
Partition pruning wrongly assumed that, for a table partitioned on a
boolean column, a clause in the form "boolcol IS NOT false" and "boolcol
IS NOT true" could be inverted to correspondingly become "boolcol IS true"
and "boolcol IS false". These are not equivalent as the NOT version
matches the opposite boolean value *and* NULLs. This incorrect assumption
meant that partition pruning pruned away partitions that could contain
NULL values.
Here we fix this by correctly not pruning partitions which could store
NULLs.
To be affected by this, the table must be partitioned by a NULLable boolean
column and queries would have to contain "boolcol IS NOT false" or "boolcol
IS NOT true". This could result in queries filtering out NULL values
with a LIST partitioned table and "ERROR: invalid strategy number 0"
for RANGE and HASH partitioned tables.
Reported-by: Alexander Lakhin
Bug: #18344
Discussion: https://postgr.es/m/18344-8d3f00bada6d09c6@postgresql.org
Backpatch-through: 12
intoasc(), a wrapper for PGTYPESinterval_to_asc that converts an
interval to its textual representation, used a plain memcpy() when
copying its result. This could miss a zero-termination in the result
string, leading to an incorrect result.
The routines in informix.c do not provide the length of their result
buffer, which would allow a replacement of strcpy() to safer strlcpy()
calls, but this requires an ABI breakage and that cannot happen in
back-branches.
Author: Oleg Tselebrovskiy
Reviewed-by: Ashutosh Bapat
Discussion: https://postgr.es/m/bf47888585149f83b276861a1662f7e4@postgrespro.ru
Backpatch-through: 12
The pgcrypto docs contained a set of links for useful reading and
technical references. These sets of links were however not actively
curated and had stale content and dead links. Rather than investing
time into maintining these, this removes them altogether since there
are lots of resources online which are actively maintained.
Backpatch to all supported versions since these links have been in
the docs for a long time.
Reported-by: Hanefi Onaldi <hanefi.onaldi@microsoft.com>
Reviewed-by: Magnus Hagander <magnus@hagander.net>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/170774255387.3279713.2822272755998870925@wrigleys.postgresql.org
Backpatch-through: v12
The macOS Finder application creates .DS_Store files in directories
when opened, which creates problems for serverside utilities which
expect all files to be PostgreSQL specific files. Skip these files
when encountered in pg_checksums, pg_rewind and pg_basebackup.
This was extracted from a larger patchset for skipping hidden files
and system files, where the concencus was to just skip these. Since
this is equally likely to happen in every version, backpatch to all
supported versions.
Reported-by: Mark Guertin <markguertin@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Tobias Bussmann <t.bussmann@gmx.net>
Discussion: https://postgr.es/m/E258CE50-AB0E-455D-8AAD-BB4FE8F882FB@gmail.com
Backpatch-through: v12
Since its introduction, pg_get_expr() has intended to silently
return NULL if called with an invalid relation OID, as can happen
when scanning the catalogs concurrently with relation drops.
However, there is a race condition: we check validity of the OID
at the start, but it could get dropped just afterward, leading to
failures. This is the cause of some intermittent instability we're
seeing in a proposed new test case, and presumably it's a hazard in
the field as well.
We can fix this by AccessShareLock-ing the target relation for the
duration of pg_get_expr(). Since we don't require any permissions
on the target relation, this is semantically a bit undesirable. But
it turns out that the set_relation_column_names() subroutine already
takes a transient AccessShareLock on that relation, and has done since
commit 2ffa740be in 2012. Given the lack of complaints about that, it
seems like there should be no harm in holding the lock a bit longer.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/31ddcc01-a71b-4e8c-9948-01d1c47293ca@eisentraut.org
We previously supposed that it was okay for different threads to
call bindtextdomain() concurrently (cf. commit 1f655fdc3).
It now emerges that there's at least one gettext implementation
in which that triggers an abort() crash, so let's stop doing that.
Add mutexes guarding libpq's and ecpglib's calls, which are the
only ones that need worry about multithreaded callers.
Note: in libpq, we could perhaps have piggybacked on
default_threadlock() to avoid defining a new mutex variable.
I judge that not terribly safe though, since libpq_gettext could
be called from code that is holding the default mutex. If that
were the first such call in the process, it'd fail. An extra
mutex is cheap insurance against unforeseen interactions.
Per bug #18312 from Christian Maurer. Back-patch to all
supported versions.
Discussion: https://postgr.es/m/18312-bbbabc8113592b78@postgresql.org
Discussion: https://postgr.es/m/264860.1707163416@sss.pgh.pa.us
Fix pthread-win32.h and pthread-win32.c to provide a more complete
emulation of POSIX pthread mutexes: define PTHREAD_MUTEX_INITIALIZER
and make sure that pthread_mutex_lock() can operate on a mutex
object that's been initialized that way. Then we don't need the
duplicative platform-specific logic in default_threadlock() and
pgtls_init(), which we'd otherwise need yet a third copy of for
an upcoming bug fix.
Also, since default_threadlock() supposes that pthread_mutex_lock()
cannot fail, try to ensure that that's actually true, by getting
rid of the malloc call that was formerly involved in initializing
an emulated mutex. We can define an extra state for the spinlock
field instead.
Also, replace the similar code in ecpglib/misc.c with this version.
While ecpglib's version at least had a POSIX-compliant API, it
also had the potential of failing during mutex init (but here,
because of CreateMutex failure rather than malloc failure). Since
all of misc.c's callers ignore failures, it seems like a wise idea
to avoid failures here too.
A further improvement in this area could be to unify libpq's and
ecpglib's implementations into a src/port/pthread-win32.c file.
But that doesn't seem like a bug fix, so I'll desist for now.
In preparation for the aforementioned bug fix, back-patch to all
supported branches.
Discussion: https://postgr.es/m/264860.1707163416@sss.pgh.pa.us
The TransactionIdInRecentPast() should return false for all the transactions
older than TransamVariables->oldestClogXid. However, the function contains
a bug in comparison FullTransactionId to TransactionID allowing full
transactions between nextXid - 2^32 and oldestClogXid - 2^31.
This commit fixes TransactionIdInRecentPast() by turning the oldestClogXid into
FullTransactionId first, then performing the comparison.
Backpatch to all supported versions.
Reported-by: Egor Chindyaskin
Bug: 18212
Discussion: https://postgr.es/m/18212-547307f8adf57262%40postgresql.org
Author: Karina Litskevich
Reviewed-by: Kyotaro Horiguchi
Backpatch-through: 12
When assertions are disabled, the built SQL statement is invalid and
you get a "syntax error". So this isn't a serious problem, but let's
avoid the assertion failure.
Backpatch to all supported versions.
Reviewed-by: Noah Misch
