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2017-07-26Update copyright in recently added filesAlvaro Herrera
2017-07-26Fix concurrent locking of tuple update chainAlvaro Herrera
If several sessions are concurrently locking a tuple update chain with nonconflicting lock modes using an old snapshot, and they all succeed, it may happen that some of them fail because of restarting the loop (due to a concurrent Xmax change) and getting an error in the subsequent pass while trying to obtain a tuple lock that they already have in some tuple version. This can only happen with very high concurrency (where a row is being both updated and FK-checked by multiple transactions concurrently), but it's been observed in the field and can have unpleasant consequences such as an FK check failing to see a tuple that definitely exists: ERROR: insert or update on table "child_table" violates foreign key constraint "fk_constraint_name" DETAIL: Key (keyid)=(123456) is not present in table "parent_table". (where the key is observably present in the table). Discussion: https://postgr.es/m/20170714210011.r25mrff4nxjhmf3g@alvherre.pgsql
2017-07-26Remove obsolete comments about functional dependenciesAlvaro Herrera
Initial submitted versions of the functional dependencies patch ignored row groups that were smaller than a configured size. However, that consideration was removed in late stages of the patch just before commit, but some comments referring to it remained. Remove them to avoid confusion. Author: Atsushi Torikoshi Discussion: https://postgr.es/m/7cfb23fc-4493-9c02-5da9-e505fd0115d2@lab.ntt.co.jp
2017-07-26Accept some of the differences in 'tidscan' test casePavan Deolasee
Most of these differences arise from the the fact that rows are fetched from multiple datanodes in XL and hence TIDs can be duplicated. There are some other differences because of EXPLAIN output. The test case does not yet pass because of other unaddressed failures.
2017-07-26Fix remaining problems in 'triggers' test case.Pavan Deolasee
We don't support different column ordering for partitions in XL. So enforce that either by ensuring consistent column ordering or accepting errors. Also we don't support triggers in XL, so some changes were necessary to take that into account.
2017-07-26Fix 'union' test case.Pavan Deolasee
Since 93cbab90b0c6fc3fc4aa515b93057127c0ee8a1b we expect that the child table has columns at the same position as the parent table. So fix the test case to follow the rule and resolve expected output differences arising from that. The test case should pass with this change.
2017-07-26Don't try to fetch table details using the old name after ExecRenameStmtPavan Deolasee
This used to work before PG 10, but some changes must have caused non-deterministic behaviour. It anyways seems unsafe to lookup the catalogs using the old name once ExecRenameStmt has finished. The lookup may or may not see the old tuple, depending on whether CommandCounterIncrement has happened in between. We now fetch the requried details before calling ExecRenameStmt and use that info for subsequent processing. This fixes some wierd issues in 'alter_table' test case where we were failing to send ALTER TABLE RENAME TO command to remote nodes and causing inconsistent catalog entries between the coordinator and the remote nodes.
2017-07-25Make PostgresNode easily subclassableAlvaro Herrera
This module becomes much more useful if we allow it to be used as base class for external projects. To achieve this, change the exported get_new_node function into a class method instead, and use the standard Perl idiom of accepting the class as first argument. This method works as expected for subclasses. The standalone function is kept for backwards compatibility, though it could be removed in pg11. Author: Chap Flackman, based on an earlier patch from Craig Ringer Discussion: https://postgr.es/m/CAMsr+YF8kO+4+K-_U4PtN==2FndJ+5Bn6A19XHhMiBykEwv0wA@mail.gmail.com
2017-07-25Fix race conditions in replication slot operationsAlvaro Herrera
It is relatively easy to get a replication slot to look as still active while one process is in the process of getting rid of it; when some other process tries to "acquire" the slot, it would fail with an error message of "replication slot XYZ is active for PID N". The error message in itself is fine, except that when the intention is to drop the slot, it is unhelpful: the useful behavior would be to wait until the slot is no longer acquired, so that the drop can proceed. To implement this, we use a condition variable so that slot acquisition can be told to wait on that condition variable if the slot is already acquired, and we make any change in active_pid broadcast a signal on the condition variable. Thus, as soon as the slot is released, the drop will proceed properly. Reported by: Tom Lane Discussion: https://postgr.es/m/11904.1499039688@sss.pgh.pa.us Authors: Petr Jelínek, Álvaro Herrera
2017-07-24Fix partitioning crashes during error reporting.Robert Haas
In various places where we reverse-map a tuple before calling ExecBuildSlotValueDescription, we neglected to ensure that the slot descriptor matched the tuple stored in it. Amit Langote and Amit Khandekar, reviewed by Etsuro Fujita Discussion: http://postgr.es/m/CAJ3gD9cqpP=WvJj=dv1ONkPWjy8ZuUaOM4_x86i3uQPas=0_jg@mail.gmail.com
2017-07-24Fix race condition in predicate-lock init code in EXEC_BACKEND builds.Tom Lane
Trading a little too heavily on letting the code path be the same whether we were creating shared data structures or only attaching to them, InitPredicateLocks() inserted the "scratch" PredicateLockTargetHash entry unconditionally. This is just wrong if we're in a postmaster child, which would only reach this code in EXEC_BACKEND builds. Most of the time, the hash_search(HASH_ENTER) call would simply report that the entry already existed, causing no visible effect since the code did not bother to check for that possibility. However, if this happened while some other backend had transiently removed the "scratch" entry, then that other backend's eventual RestoreScratchTarget would suffer an assert failure; this appears to be the explanation for a recent failure on buildfarm member culicidae. In non-assert builds, there would be no visible consequences there either. But nonetheless this is a pretty bad bug for EXEC_BACKEND builds, for two reasons: 1. Each new backend would perform the hash_search(HASH_ENTER) call without holding any lock that would prevent concurrent access to the PredicateLockTargetHash hash table. This creates a low but certainly nonzero risk of corruption of that hash table. 2. In the event that the race condition occurred, by reinserting the scratch entry too soon, we were defeating the entire purpose of the scratch entry, namely to guarantee that transaction commit could move hash table entries around with no risk of out-of-memory failure. The odds of an actual OOM failure are quite low, but not zero, and if it did happen it would again result in corruption of the hash table. The user-visible symptoms of such corruption are a little hard to predict, but would presumably amount to misbehavior of SERIALIZABLE transactions that'd require a crash or postmaster restart to fix. To fix, just skip the hash insertion if IsUnderPostmaster. I also inserted a bunch of assertions that the expected things happen depending on whether IsUnderPostmaster is true. That might be overkill, since most comparable code in other functions isn't quite that paranoid, but once burnt twice shy. In passing, also move a couple of lines to places where they seemed to make more sense. Diagnosis of problem by Thomas Munro, patch by me. Back-patch to all supported branches. Discussion: https://postgr.es/m/10593.1500670709@sss.pgh.pa.us
2017-07-24When WCOs are present, disable direct foreign table modification.Robert Haas
If the user modifies a view that has CHECK OPTIONs and this gets translated into a modification to an underlying relation which happens to be a foreign table, the check options should be enforced. In the normal code path, that was happening properly, but it was not working properly for "direct" modification because the whole operation gets pushed to the remote side in that case and we never have an option to enforce the constraint against individual tuples. Fix by disabling direct modification when there is a need to enforce CHECK OPTIONs. Etsuro Fujita, reviewed by Kyotaro Horiguchi and by me. Discussion: http://postgr.es/m/f8a48f54-6f02-9c8a-5250-9791603171ee@lab.ntt.co.jp
2017-07-24Ensure that pg_get_ruledef()'s output matches pg_get_viewdef()'s.Tom Lane
Various cases involving renaming of view columns are handled by having make_viewdef pass down the view's current relation tupledesc to get_query_def, which then takes care to use the column names from the tupledesc for the output column names of the SELECT. For some reason though, we'd missed teaching make_ruledef to do similarly when it is printing an ON SELECT rule, even though this is exactly the same case. The results from pg_get_ruledef would then be different and arguably wrong. In particular, this breaks pre-v10 versions of pg_dump, which in some situations would define views by means of emitting a CREATE RULE ... ON SELECT command. Third-party tools might not be happy either. In passing, clean up some crufty code in make_viewdef; we'd apparently modernized the equivalent code in make_ruledef somewhere along the way, and missed this copy. Per report from Gilles Darold. Back-patch to all supported versions. Discussion: https://postgr.es/m/ec05659a-40ff-4510-fc45-ca9d965d0838@dalibo.com
2017-07-24Be more consistent about errors for opfamily member lookup failures.Tom Lane
Add error checks in some places that were calling get_opfamily_member or get_opfamily_proc and just assuming that the call could never fail. Also, standardize the wording for such errors in some other places. None of these errors are expected in normal use, hence they're just elog not ereport. But they may be handy for diagnosing omissions in custom opclasses. Rushabh Lathia found the oversight in RelationBuildPartitionKey(); I found the others by grepping for all callers of these functions. Discussion: https://postgr.es/m/CAGPqQf2R9Nk8htpv0FFi+FP776EwMyGuORpc9zYkZKC8sFQE3g@mail.gmail.com
2017-07-24MSVC: Finish clean.bat build artifact coverage.Noah Misch
With this, "git clean -dnx" is clear after a "clean dist" following a build. Preserve sql_help.h in non-dist cleans, like the Makefile does.
2017-07-24MSVC: Accept tcl86.lib in addition to tcl86t.lib.Noah Misch
ActiveTcl8.6.4.1.299124-win32-x86_64-threaded.exe ships just tcl86.lib. Back-patch to 9.2, like the commit recognizing tcl86t.lib.
2017-07-24Accept some obvious regression differences in the 'join' test casePavan Deolasee
These are only placements of Remote FQS or Remote Subplan nodes in the newly added explain plans in the test case. There are some remaining failures in the test case which will need more scrutiny.
2017-07-23Fix pg_dump's handling of event triggers.Tom Lane
pg_dump with the --clean option failed to emit DROP EVENT TRIGGER commands for event triggers. In a closely related oversight, it also did not emit ALTER OWNER commands for event triggers. Since only superusers can create event triggers, the latter oversight is of little practical consequence ... but if we're going to record an owner for event triggers, then surely pg_dump should preserve it. Per complaint from Greg Atkins. Back-patch to 9.3 where event triggers were introduced. Discussion: https://postgr.es/m/20170722191142.yi4e7tzcg3iacclg@gmail.com
2017-07-22Improve comments about partitioned hash table freelists.Tom Lane
While I couldn't find any live bugs in commit 44ca4022f, the comments seemed pretty far from adequate; in particular it was not made plain that "borrowing" entries from other freelists is critical for correctness. Try to improve the commentary. A couple of very minor code style tweaks, as well. Discussion: https://postgr.es/m/10593.1500670709@sss.pgh.pa.us
2017-07-22Update expected results for collate.linux.utf8 regression test.Tom Lane
I believe this changed as a consequence of commit 54baa4813: trying to clone the "C" collation now produces a true clone with collencoding -1, hence the error message if it's duplicate no longer specifies an encoding. Per buildfarm member crake, which apparently hadn't been running this test for the last few weeks.
2017-07-22Fix typo in commentAlvaro Herrera
Commit fd31cd265138 renamed the variable to skipping_blocks, but forgot to update this comment. Noticed while inspecting code.
2017-07-21Doc: update versioning information in libpq.sgml.Tom Lane
The descriptions of PQserverVersion and PQlibVersion hadn't been updated for the new two-part version-numbering approach. Fix that. In passing, remove some trailing whitespace elsewhere in the file.
2017-07-21pg_rewind: Fix some problems when copying files >2GB.Robert Haas
When incrementally updating a file larger than 2GB, the old code could either fail outright (if the client asked the server for bytes beyond the 2GB boundary) or fail to copy all the blocks that had actually been modified (if the server reported a file size to the client in excess of 2GB), resulting in data corruption. Generally, such files won't occur anyway, but they might if using a non-default segment size or if there the directory contains stray files unrelated to PostgreSQL. Fix by a more prudent choice of data types. Even with these improvements, this code still uses a mix of different types (off_t, size_t, uint64, int64) to represent file sizes and offsets, not all of which necessarily have the same width or signedness, so further cleanup might be in order here. However, at least now they all have the potential to be 64 bits wide on 64-bit platforms. Kuntal Ghosh and Michael Paquier, with a tweak by me. Discussion: http://postgr.es/m/CAGz5QC+8gbkz=Brp0TgoKNqHWTzonbPtPex80U0O6Uh_bevbaA@mail.gmail.com
2017-07-21Stabilize postgres_fdw regression tests.Tom Lane
The new test cases added in commit 8bf58c0d9 turn out to have output that can vary depending on the lc_messages setting prevailing on the test server. Hide the remote end's error messages to ensure stable output. This isn't a terribly desirable solution; we'd rather know that the connection failed for the expected reason and not some other one. But there seems little choice for the moment. Per buildfarm. Discussion: https://postgr.es/m/18419.1500658570@sss.pgh.pa.us
2017-07-21pg_rewind: Fix busted sanity check.Robert Haas
As written, the code would only fail the sanity check if none of the columns returned by the server were of the expected type, but we want it to fail if even one column is not of the expected type. Discussion: http://postgr.es/m/CA+TgmoYuY5zW7JEs+1hSS1D=V5K8h1SQuESrq=bMNeo0B71Sfw@mail.gmail.com
2017-07-21Re-establish postgres_fdw connections after server or user mapping changes.Tom Lane
Previously, postgres_fdw would keep on using an existing connection even if the user did ALTER SERVER or ALTER USER MAPPING commands that should affect connection parameters. Teach it to watch for catcache invals on these catalogs and re-establish connections when the relevant catalog entries change. Per bug #14738 from Michal Lis. In passing, clean up some rather crufty decisions in commit ae9bfc5d6 about where fields of ConnCacheEntry should be reset. We now reset all the fields whenever we open a new connection. Kyotaro Horiguchi, reviewed by Ashutosh Bapat and myself. Back-patch to 9.3 where postgres_fdw appeared. Discussion: https://postgr.es/m/20170710113917.7727.10247@wrigleys.postgresql.org
2017-07-21Fix double shared memory allocation.Teodor Sigaev
SLRU buffer lwlocks are allocated twice by oversight in commit fe702a7b3f9f2bc5bf6d173166d7d55226af82c8 where that locks were moved to separate tranche. The bug doesn't have user-visible effects except small overspending of shared memory. Backpatch to 9.6 where it was introduced. Alexander Korotkov with small editorization by me.
2017-07-21Make the new partition regression tests locale-independent.Dean Rasheed
The order of partitions listed by \d+ is in general locale-dependent. Rename the partitions in the test added by d363d42bb9 to force them to be listed in a consistent order.
2017-07-21Use MINVALUE/MAXVALUE instead of UNBOUNDED for range partition bounds.Dean Rasheed
Previously, UNBOUNDED meant no lower bound when used in the FROM list, and no upper bound when used in the TO list, which was OK for single-column range partitioning, but problematic with multiple columns. For example, an upper bound of (10.0, UNBOUNDED) would not be collocated with a lower bound of (10.0, UNBOUNDED), thus making it difficult or impossible to define contiguous multi-column range partitions in some cases. Fix this by using MINVALUE and MAXVALUE instead of UNBOUNDED to represent a partition column that is unbounded below or above respectively. This syntax removes any ambiguity, and ensures that if one partition's lower bound equals another partition's upper bound, then the partitions are contiguous. Also drop the constraint prohibiting finite values after an unbounded column, and just document the fact that any values after MINVALUE or MAXVALUE are ignored. Previously it was necessary to repeat UNBOUNDED multiple times, which was needlessly verbose. Note: Forces a post-PG 10 beta2 initdb. Report by Amul Sul, original patch by Amit Langote with some additional hacking by me. Discussion: https://postgr.es/m/CAAJ_b947mowpLdxL3jo3YLKngRjrq9+Ej4ymduQTfYR+8=YAYQ@mail.gmail.com
2017-07-20In v10 release notes, call out sequence changes as a compatibility item.Tom Lane
The previous description didn't make it clear that this change potentially breaks applications, partly because the entry wasn't even in the compatibility-hazard section. Move and clarify. Discussion: https://postgr.es/m/603f3f0a-f89d-ae8b-1da9-a92fac16086d@enterprisedb.com
2017-07-20Doc: clarify description of degenerate NATURAL joins.Tom Lane
Claiming that NATURAL JOIN is equivalent to CROSS JOIN when there are no common column names is only strictly correct if it's an inner join; you can't say e.g. CROSS LEFT JOIN. Better to explain it as meaning JOIN ON TRUE, instead. Per a suggestion from David Johnston. Discussion: https://postgr.es/m/CAKFQuwb+mYszQhDS9f_dqRrk1=Pe-S6D=XMkAXcDf4ykKPmgKQ@mail.gmail.com
2017-07-20Fix dumping of outer joins with empty qual lists.Tom Lane
Normally, a JoinExpr would have empty "quals" only if it came from CROSS JOIN syntax. However, it's possible to get to this state by specifying NATURAL JOIN between two tables with no common column names, and there might be other ways too. The code previously printed no ON clause if "quals" was empty; that's right for CROSS JOIN but syntactically invalid if it's some type of outer join. Fix by printing ON TRUE in that case. This got broken by commit 2ffa740be, which stopped using NATURAL JOIN syntax in ruleutils output due to its brittleness in the face of column renamings. Back-patch to 9.3 where that commit appeared. Per report from Tushar Ahuja. Discussion: https://postgr.es/m/98b283cd-6dda-5d3f-f8ac-87db8c76a3da@enterprisedb.com
2017-07-19Add static assertions about pg_control fitting into one disk sector.Tom Lane
When pg_control was first designed, sizeof(ControlFileData) was small enough that a comment seemed like plenty to document the assumption that it'd fit into one disk sector. Now it's nearly 300 bytes, raising the possibility that somebody would carelessly add enough stuff to create a problem. Let's add a StaticAssertStmt() to ensure that the situation doesn't pass unnoticed if it ever occurs. While at it, rename PG_CONTROL_SIZE to PG_CONTROL_FILE_SIZE to make it clearer what that symbol means, and convert the existing runtime comparisons of sizeof(ControlFileData) vs. PG_CONTROL_FILE_SIZE to be static asserts --- we didn't have that technology when this code was first written. Discussion: https://postgr.es/m/9192.1500490591@sss.pgh.pa.us
2017-07-19Doc: add missing note about permissions needed to change log_lock_waits.Tom Lane
log_lock_waits is PGC_SUSET, but config.sgml lacked the standard boilerplate sentence noting that. Report: https://postgr.es/m/20170719100838.19352.16320@wrigleys.postgresql.org
2017-07-18Improve make_tsvector() to handle empty input, and simplify its callers.Tom Lane
It seemed a bit silly that each caller of make_tsvector() was laboriously special-casing the situation where no lexemes were found, when it would be easy and much more bullet-proof to make make_tsvector() handle that.
2017-07-18Fix serious performance problems in json(b) to_tsvector().Tom Lane
In an off-list followup to bug #14745, Bob Jones complained that to_tsvector() on a 2MB jsonb value took an unreasonable amount of time and space --- enough to draw the wrath of the OOM killer on his machine. On my machine, his example proved to require upwards of 18 seconds and 4GB, which seemed pretty bogus considering that to_tsvector() on the same data treated as text took just a couple hundred msec and 10 or so MB. On investigation, the problem is that the implementation scans each string element of the json(b) and converts it to tsvector separately, then applies tsvector_concat() to join those separate tsvectors. The unreasonable memory usage came from leaking every single one of the transient tsvectors --- but even without that mistake, this is an O(N^2) or worse algorithm, because tsvector_concat() has to repeatedly process the words coming from earlier elements. We can fix it by accumulating all the lexeme data and applying make_tsvector() just once. As a side benefit, that also makes the desired adjustment of lexeme positions far cheaper, because we can just tweak the running "pos" counter between JSON elements. In passing, try to make the explanation of that tweak more intelligible. (I didn't think that a barely-readable comment far removed from the actual code was helpful.) And do some minor other code beautification.
2017-07-18Doc: fix thinko in v10 release notes.Tom Lane
s/log_destination/log_directory/, per Jov in bug #14749. Report: https://postgr.es/m/20170718082444.9229.99690@wrigleys.postgresql.org
2017-07-18Reverse-convert row types in ExecWithCheckOptions.Robert Haas
Just as we already do in ExecConstraints, and for the same reason: to improve the quality of error messages. Etsuro Fujita, reviewed by Amit Langote Discussion: http://postgr.es/m/56e0baa8-e458-2bbb-7936-367f7d832e43@lab.ntt.co.jp
2017-07-18Use a real RT index when setting up partition tuple routing.Robert Haas
Before, we always used a dummy value of 1, but that's not right when the partitioned table being modified is inside of a WITH clause rather than part of the main query. Amit Langote, reported and reviewd by Etsuro Fujita, with a comment change by me. Discussion: http://postgr.es/m/ee12f648-8907-77b5-afc0-2980bcb0aa37@lab.ntt.co.jp
2017-07-17Accept changes in foreign_data test due to unsupported FDWTomas Vondra
Postgres-XL does not support Foreign Data Wrappers, so accept failures and output differences in the foreign_data regression test as expected.
2017-07-17Accept failures in triggers test du to unsupported featuresTomas Vondra
Postgres-XL does not support triggers, naturally causing many failures in the triggers regression test. So treat the error messages as expected behavior and remove the NOTICEs produced by the triggers. Another failure was caused by INSERT in a subquery, which is another feature unsupported by Postgres-XL.
2017-07-17Accept two query plans in the join regression testTomas Vondra
Both plans keep the same join algorithm as on PostgreSQL, and the plans match those produced by Postgres-XL 9.5.
2017-07-17Resolve failures related to pg_node_tree type inputTomas Vondra
The input function for pg_node_tree pseudotype simply returns an error, essentially disabling input from text. Some of the regression tests do CREATE TABLE t AS SELECT * FROM pg_class; or something like that, which works fine on PostgreSQL, but it fails on Postgres-XL as we need to send data between nodes. Unfortunately the pg_class now contains pg_node_tree column (relpartbound), causing falure when reading the column on the remote node. So instead use another catalogue, for example pg_attribute, which does not contain any such column.
2017-07-17Doc: explain dollar quoting in the intro part of the pl/pgsql chapter.Tom Lane
We're throwing people into the guts of the syntax with not much context; let's back up one step and point out that this goes inside a literal in a CREATE FUNCTION command. Per suggestion from Kurt Kartaltepe. Discussion: https://postgr.es/m/CACawnnyWAmH+au8nfZhLiFfWKjXy4d0kY+eZWfcxPRnjVfaa_Q@mail.gmail.com
2017-07-17Drop the foo table in rangefuncs regression tesTomas Vondra
The table was made non-temporary by commit e98209019b4d2012, but it was not dropped, wich caused failures in the returning regression test. So add the missing DROP TABLE.
2017-07-17Improve legibility of numeric literalAndrew Dunstan
2017-07-17Merge large_object.sql test into largeobject.source.Tom Lane
It seems pretty confusing to have tests named both largeobject and large_object. The latter is of very recent vintage (commit ff992c074), so get rid of it in favor of merging into the former. Also, enable the LO comment test that was added by commit 70ad7ed4e, since the later commit added the then-missing pg_upgrade functionality. The large_object.sql test case is almost completely redundant with that, but not quite: it seems like creating a user-defined LO with an OID in the system range might be an interesting case for pg_upgrade, so let's keep it. Like the earlier patch, back-patch to all supported branches. Discussion: https://postgr.es/m/18665.1500306372@sss.pgh.pa.us
2017-07-17Use usleep instead of select for timeouts in PostgresNode.pmAndrew Dunstan
select() for pure timeouts is not portable, and in particular doesn't work on Windows. Discussion: https://postgr.es/m/186943e0-3405-978d-b19d-9d3335427c86@2ndQuadrant.com
2017-07-17hash: Fix write-ahead logging bugs related to init forks.Robert Haas
One, logging for CREATE INDEX was oblivious to the fact that when an unlogged table is created, *only* operations on the init fork should be logged. Two, init fork buffers need to be flushed after they are written; otherwise, a filesystem-level copy following recovery may do the wrong thing. (There may be a better fix for this issue than the one used here, but this is transposed from the similar logic already present in XLogReadBufferForRedoExtended, and a broader refactoring after beta2 seems inadvisable.) Amit Kapila, reviewed by Ashutosh Sharma, Kyotaro Horiguchi, and Michael Paquier Discussion: http://postgr.es/m/CAA4eK1JpcMsEtOL_J7WODumeEfyrPi7FPYHeVdS7fyyrCrgp4w@mail.gmail.com
2017-07-17MSVC: Don't link libpgcommon into pgcrypto.Noah Misch
Doing so was useful in 273c458a2b3a0fb73968020ea5e9e35eb6928967 but became obsolete when 818fd4a67d610991757b610755e3065fb99d80a5 caused postgres.exe to provide the relevant symbols. No other loadable module links to libpgcommon directly.