summaryrefslogtreecommitdiff
path: root/src
AgeCommit message (Collapse)Author
2018-05-05Remove extra newlines after PQerrorMessage()Peter Eisentraut
2018-05-05Fix scenario where streaming standby gets stuck at a continuation record.Heikki Linnakangas
If a continuation record is split so that its first half has already been removed from the master, and is only present in pg_wal, and there is a recycled WAL segment in the standby server that looks like it would contain the second half, recovery would get stuck. The code in XLogPageRead() incorrectly started streaming at the beginning of the WAL record, even if we had already read the first page. Backpatch to 9.4. In principle, older versions have the same problem, but without replication slots, there was no straightforward mechanism to prevent the master from recycling old WAL that was still needed by standby. Without such a mechanism, I think it's reasonable to assume that there's enough slack in how many old segments are kept around to not run into this, or you have a WAL archive. Reported by Jonathon Nelson. Analysis and patch by Kyotaro HORIGUCHI, with some extra comments by me. Discussion: https://www.postgresql.org/message-id/CACJqAM3xVz0JY1XFDKPP%2BJoJAjoGx%3DGNuOAshEDWCext7BFvCQ%40mail.gmail.com
2018-05-04Don't mark pages all-visible spuriouslyAlvaro Herrera
Dan Wood diagnosed a long-standing problem that pages containing tuples that are locked by multixacts containing live lockers may spuriously end up as candidates for getting their all-visible flag set. This has the long-term effect that multixacts remain unfrozen; this may previously pass undetected, but since commit XYZ it would be reported as "ERROR: found multixact 134100944 from before relminmxid 192042633" because when a later vacuum tries to freeze the page it detects that a multixact that should have gotten frozen, wasn't. Dan proposed a (correct) patch that simply sets a variable to its correct value, after a bogus initialization. But, per discussion, it seems better coding to avoid the bogus initializations altogether, since they could give rise to more bugs later. Therefore this fix rewrites the logic a little bit to avoid depending on the bogus initializations. This bug was part of a family introduced in 9.6 by commit a892234f830e; later, commit 38e9f90a227d fixed most of them, but this one was unnoticed. Authors: Dan Wood, Pavan Deolasee, Álvaro Herrera Reviewed-by: Masahiko Sawada, Pavan Deolasee, Álvaro Herrera Discussion: https://postgr.es/m/84EBAC55-F06D-4FBE-A3F3-8BDA093CE3E3@amazon.com
2018-05-04Provide for testing on python3 modules when under MSVCAndrew Dunstan
This should have been done some years ago as promised in commit c4dcdd0c2. However, better late than never. Along the way do a little housekeeping, including using a simpler test for the python version being tested, and removing a redundant subroutine parameter. These changes only apply back to release 9.5. Backpatch to all live releases.
2018-05-04Allow MSYS as well as MINGW in Msys unameAndrew Dunstan
Msys2's uname -s outputs a string beginning MSYS rather than MINGW as is output by Msys. Allow either in pg_upgrade's test.sh. Backpatch to all live branches.
2018-05-04Sync our copy of the timezone library with IANA release tzcode2018e.Tom Lane
The non-cosmetic changes involve teaching the "zic" tzdata compiler about negative DST. While I'm not currently intending that we start using negative-DST data right away, it seems possible that somebody would try to use our copy of zic with bleeding-edge IANA data. So we'd better be out in front of this change code-wise, even though it doesn't matter for the data file we're shipping. Discussion: https://postgr.es/m/30996.1525445902@sss.pgh.pa.us
2018-05-04Fix precedence problem in new Perl code.Tom Lane
I think this bit of commit 1f1cd9b5d didn't do quite what I meant :-(
2018-05-04pg_dump: Use current_database() instead of PQdb()Peter Eisentraut
For querying pg_database about information about the database being dumped, look up by using current_database() instead of the value obtained from PQdb(). When using a connection proxy, the value from PQdb() might not be the real name of the database.
2018-05-04Don't truncate away non-key attributes for leftmost downlinks.Teodor Sigaev
nbtsort.c does not need to truncate away non-key attributes for the minimum key of the leftmost page on a level, since this is only used to build a minus infinity downlink for the level's leftmost page. Truncating away non-key attributes in advance of truncating away all attributes in _bt_sortaddtup() does not affect the correctness of CREATE INDEX, but it is misleading. Author: Peter Geoghegan Discussion: https://www.postgresql.org/message-id/CAH2-WzkAS2M3ussHG-s_Av=Zo6dPjOxyu5fNRkYnxQV+YzGQ4w@mail.gmail.com
2018-05-04Re-think predicate locking on GIN indexes.Teodor Sigaev
The principle behind the locking was not very well thought-out, and not documented. Add a section in the README to explain how it's supposed to work, and change the code so that it actually works that way. This fixes two bugs: 1. If fast update was turned on concurrently, subsequent inserts to the pending list would not conflict with predicate locks that were acquired earlier, on entry pages. The included 'predicate-gin-fastupdate' test demonstrates that. To fix, make all scans acquire a predicate lock on the metapage. That lock represents a scan of the pending list, whether or not there is a pending list at the moment. Forget about the optimization to skip locking/checking for locks, when fastupdate=off. 2. If a scan finds no match, it still needs to lock the entry page. The point of predicate locks is to lock the gabs between values, whether or not there is a match. The included 'predicate-gin-nomatch' test tests that case. In addition to those two bug fixes, this removes some unnecessary locking, following the principle laid out in the README. Because all items in a posting tree have the same key value, a lock on the posting tree root is enough to cover all the items. (With a very large posting tree, it would possibly be better to lock the posting tree leaf pages instead, so that a "skip scan" with a query like "A & B", you could avoid unnecessary conflict if a new tuple is inserted with A but !B. But let's keep this simple.) Also, some spelling fixes. Author: Heikki Linnakangas with some editorization by me Review: Andrey Borodin, Alexander Korotkov Discussion: https://www.postgresql.org/message-id/0b3ad2c2-2692-62a9-3a04-5724f2af9114@iki.fi
2018-05-03Update expected files for older Python versionsPeter Eisentraut
neglected in commit fa03769e4c4bf0911da71fba2501006b05ea195a
2018-05-03Blindly try to fix MSVC build's use of genbki.pl and Gen_fmgrtab.pl.Tom Lane
We need to use a stamp file to record the runs of these scripts, as is done on the Unix side. I think I got it right, but can't test. While at it, extend this handmade dependency logic to also check the generating script files, as the makefiles do. Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
2018-05-03Avoid overwriting unchanged output files in genbki.pl and Gen_fmgrtab.pl.Tom Lane
If a particular output file already exists with the contents it should have, leave it alone, so that its mod timestamp is not advanced. In builds using --enable-depend, this can avoid the need to recompile .c files whose included files didn't actually change. It's not clear whether it saves much of anything for users of ccache; but the cost of doing the file comparisons seems to be negligible, so we might as well do it. For developers using the MSVC toolchain, this will create a regression: msvc/Solution.pm will sometimes run genbki.pl or Gen_fmgrtab.pl unnecessarily. I'll look into fixing that separately. Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
2018-05-03Rearrange makefile rules for running Gen_fmgrtab.pl.Tom Lane
Make these rules look more like the ones associated with genbki.pl, to wit: * Use a stamp file to record when we last ran the script, instead of relying on the timestamps of the individual output files. * Take the knowledge out of backend/Makefile and put it in utils/Makefile where it belongs. I moved down the handling of errcodes.h and probes.h too, although those continue to be built by separate processes. In itself, this is just much-needed cleanup with little practical effect. However, by decoupling these makefile rules from the timestamps of the generated header files, we open the door to not advancing those timestamps unnecessarily, which will be taken advantage of by the next commit. msvc/Solution.pm should be taught to do things similarly, but I'll leave that for another commit. Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
2018-05-03Tweak tests to support Python 3.7Peter Eisentraut
Python 3.7 removes the trailing comma in the repr() of BaseException (see <https://bugs.python.org/issue30399>), leading to test output differences. Work around that by composing the equivalent test output in a more manual way.
2018-05-03Add HOLD_INTERRUPTS section into FinishPreparedTransaction.Teodor Sigaev
If an interrupt arrives in the middle of FinishPreparedTransaction and any callback decide to call CHECK_FOR_INTERRUPTS (e.g. RemoveTwoPhaseFile can write a warning with ereport, which checks for interrupts) then it's possible to leave current GXact undeleted. Backpatch to all supported branches Stas Kelvich Discussion: ihttps://www.postgresql.org/message-id/3AD85097-A3F3-4EBA-99BD-C38EDF8D2949@postgrespro.ru
2018-05-03Fix pg_dump support for pre-8.2 versionsTeodor Sigaev
Unify indnkeys/indnatts/indnkeyatts usage for all version of query to get index information, remove indnkeys column from query as unused. Author: Marina Polyakova Noticed by: Peter Eisentraut
2018-05-03Further improve code for probing the availability of ARM CRC instructions.Tom Lane
Andrew Gierth pointed out that commit 1c72ec6f4 would yield the wrong answer on big-endian ARM systems, because the data being CRC'd would be different. To fix that, and avoid the rather unsightly hard-wired constant, simply compare the hardware and software implementations' results. While we're at it, also log the resulting decision at DEBUG1, and error out if the hw and sw results unexpectedly differ. Also, since this file must compile for both frontend and backend, avoid incorrect dependencies on backend-only headers. In passing, add a comment to postmaster.c about when the CRC function pointer will get initialized. Thomas Munro, based on complaints from Andrew Gierth and Tom Lane Discussion: https://postgr.es/m/HE1PR0801MB1323D171938EABC04FFE7FA9E3110@HE1PR0801MB1323.eurprd08.prod.outlook.com
2018-05-03Fix SPI error cleanup and memory leakPeter Eisentraut
Since the SPI stack has been moved from TopTransactionContext to TopMemoryContext, setting _SPI_stack to NULL in AtEOXact_SPI() leaks memory. In fact, we don't need to do that anymore: We just leave the allocated stack around for the next SPI use. Also, refactor the SPI cleanup so that it is run both at transaction end and when returning to the main loop on an exception. The latter is necessary when a procedure calls a COMMIT or ROLLBACK command that itself causes an error.
2018-05-02Improve our method for probing the availability of ARM CRC instructions.Tom Lane
Instead of depending on glibc's getauxval() function, just try to execute the CRC code, and trap SIGILL if that happens. Thomas Munro Discussion: https://postgr.es/m/HE1PR0801MB1323D171938EABC04FFE7FA9E3110@HE1PR0801MB1323.eurprd08.prod.outlook.com
2018-05-02Suppress some compiler warnings in plperl on Windows.Tom Lane
Perl's XSUB.h header defines macros to replace libc functions. Our header port_win32.h does something similar earlier, so XSUB.h causes compiler warnings about macro redefinition. Undefine our macros before including XSUB.h. Thomas Munro Discussion: https://postgr.es/m/CAEepm%3D3%3DTDYEXUEcHpEx%2BTwc31wo7PA0oBAiNt6sWmq93MW02A%40mail.gmail.com
2018-05-02Fix assorted compiler warnings seen in the buildfarm.Tom Lane
Failure to use DatumGetFoo/FooGetDatum macros correctly, or at all, causes some warnings about sign conversion. This is just cosmetic at the moment but in principle it's a type violation, so clean up the instances I could find. autoprewarm.c and sharedfileset.c contained code that unportably assumed that pid_t is the same size as int. We've variously dealt with this by casting pid_t to int or to unsigned long for printing purposes; I went with the latter. Fix uninitialized-variable warning in RestoreGUCState. This is a live bug in some sense, but of no great significance given that nobody is very likely to care what "line number" is associated with a GUC that hasn't got a source file recorded.
2018-05-02Fix bogus code for extracting extended-statistics data from syscache.Tom Lane
statext_dependencies_load and statext_ndistinct_load were not up to snuff, in addition to being randomly different from each other. In detail: * Deserialize the fetched bytea value before releasing the syscache entry, not after. This mistake causes visible regression test failures when running with -DCATCACHE_FORCE_RELEASE. Since it's not exposed by -DCLOBBER_CACHE_ALWAYS, I think there may be no production hazard here at present, but it's at least a latent bug. * Use DatumGetByteaPP not DatumGetByteaP to save a detoasting cycle for short stats values; the deserialize function has to be, and is, prepared for short-header values since its other caller uses PP. * Use a test-and-elog for null stats values in both functions, rather than a test-and-elog in one case and an Assert in the other. Perhaps Asserts would be sufficient in both cases, but I don't see a good argument for them being different. * Minor cosmetic changes to make these functions more visibly alike. Backpatch to v10 where this code came in. Amit Langote, minor additional hacking by me Discussion: https://postgr.es/m/1349aabb-3a1f-6675-9fc0-65e2ce7491dd@lab.ntt.co.jp
2018-05-02Fix some sloppiness in the new BufFileSize() and BufFileAppend() functions.Heikki Linnakangas
There were three related issues: * BufFileAppend() incorrectly reset the seek position on the 'source' file. As a result, if you had called BufFileRead() on the file before calling BufFileAppend(), it got confused, and subsequent calls would read/write at wrong position. * BufFileSize() did not work with files opened with BufFileOpenShared(). * FileGetSize() only worked on temporary files. To fix, change the way BufFileSize() works so that it works on shared files. Remove FileGetSize() altogether, as it's no longer needed. Remove buffilesize from TapeShare struct, as the leader process can simply call BufFileSize() to get the tape's size, there's no need to pass it through shared memory anymore. Discussion: https://www.postgresql.org/message-id/CAH2-WznEDYe_NZXxmnOfsoV54oFkTdMy7YLE2NPBLuttO96vTQ@mail.gmail.com
2018-05-02Fix compiler warning on Windows.Tom Lane
Commit 41c912cad caused MSVC to complain that not all control paths return a value. Thomas Munro Discussion: https://postgr.es/m/CAEepm%3D3%3DTDYEXUEcHpEx%2BTwc31wo7PA0oBAiNt6sWmq93MW02A%40mail.gmail.com
2018-05-02Change SIZEOF_BOOL to 1 for Windows.Tom Lane
For some reason it was previously defined as 0, which is silly. The only effect was to disable use of <stdbool.h>, which commit b2328bf62 intended to make possible. Thomas Munro Discussion: https://postgr.es/m/CAEepm%3D3%3DTDYEXUEcHpEx%2BTwc31wo7PA0oBAiNt6sWmq93MW02A%40mail.gmail.com
2018-05-01Further -Wimplicit-fallthrough cleanup.Andres Freund
Tom's earlier commit in 41c912cad159 didn't update a few cases that are only encountered with the non-standard --with-llvm config flag. Additionally there's also one case that appears to be a deficiency in gcc's (up to trunk as of a few days ago) detection of "fallthrough" comments - changing the placement slightly fixes that. Author: Andres Freund Discussion: https://postgr.es/m/20180502003239.wfnqu7ekz7j7imm4@alap3.anarazel.de
2018-05-01Fix some assorted compiler warnings on Windows.Tom Lane
Don't overflow the result type of constant expressions. Don't negate unsigned types. Define HAVE_STDBOOL_H for Visual C++ 2013 and later. Thomas Munro Reviewed-By: Michael Paquier and Tom Lane Discussion: https://postgr.es/m/CAEepm%3D3%3DTDYEXUEcHpEx%2BTwc31wo7PA0oBAiNt6sWmq93MW02A%40mail.gmail.com
2018-05-01Clean up warnings from -Wimplicit-fallthrough.Tom Lane
Recent gcc can warn about switch-case fall throughs that are not explicitly labeled as intentional. This seems like a good thing, so clean up the warnings exposed thereby by labeling all such cases with comments that gcc will recognize. In files that already had one or more suitable comments, I generally matched the existing style of those. Otherwise I went with /* FALLTHROUGH */, which is one of the spellings approved at the more-restrictive-than-default level -Wimplicit-fallthrough=4. (At the default level you can also spell it /* FALL ?THRU */, and it's not picky about case. What you can't do is include additional text in the same comment, so some existing comments containing versions of this aren't good enough.) Testing with gcc 8.0.1 (Fedora 28's current version), I found that I also had to put explicit "break"s after elog(ERROR) or ereport(ERROR); apparently, for this purpose gcc doesn't recognize that those don't return. That seems like possibly a gcc bug, but it's fine because in most places we did that anyway; so this amounts to a visit from the style police. Discussion: https://postgr.es/m/15083.1525207729@sss.pgh.pa.us
2018-05-01Improve representation of 'moved partitions' indicator on deleted tuples.Andres Freund
Previously a tuple that has been moved to a different partition (see f16241bef7c), set the block number on the old tuple to an invalid value to indicate that fact. But the tuple offset was left untouched. That turned out to trigger a wal_consistency_checking failure as reported by Peter Geoghegan, as the offset wasn't always overwritten during WAL replay. Heikki observed that we're wasting valuable data by not putting information also in the offset. Thus set that to MovedPartitionsOffsetNumber when a tuple indicates it has moved. We continue to set the block number to MovedPartitionsBlockNumber, as that seems more likely to cause problems for code not updated to know about moved tuples. As t_ctid's offset number is now always set, this refinement also fixes the wal_consistency_checking issue. This technically is a minor disk format break, with previously created moved tuples not being recognized anymore. But since there not even has been a beta release since f16241bef7c... Reported-By: Peter Geoghegan Author: Heikki Linnakangas, Amul Sul Discussion: https://postgr.es/m/CAH2-Wzm9ty+1BX7-GMNJ=xPRg67oJTVeDNdA9LSyJJtMgRiCMA@mail.gmail.com
2018-05-01Fix interaction of foreign tuple routing with remote triggers.Robert Haas
Without these fixes, changes to the inserted tuple made by remote triggers are ignored when building local RETURNING tuples. In the core code, call ExecInitRoutingInfo at a later point from within ExecInitPartitionInfo so that the FDW callback gets invoked after the returning list has been built. But move CheckValidResultRel out of ExecInitRoutingInfo so that it can happen at an earlier stage. In postgres_fdw, refactor assorted deparsing functions to work with the RTE rather than the PlannerInfo, which saves us having to construct a fake PlannerInfo in cases where we don't have a real one. Then, we can pass down a constructed RTE that yields the correct deparse result when no real one exists. Unfortunately, this necessitates a hack that understands how the core code manages RT indexes for update tuple routing, which is ugly, but we don't have a better idea right now. Original report, analysis, and patch by Etsuro Fujita. Heavily refactored by me. Then worked over some more by Amit Langote. Discussion: http://postgr.es/m/5AD4882B.10002@lab.ntt.co.jp
2018-05-01Remove investigative code for can't-reattach-to-shared-memory errors.Tom Lane
Revert commits 23078689a, 73042b8d1, ce07aff48, f7df8043f, 6ba0cc4bd, eb16011f4, 68e7e973d, 63ca350ef. We still have a problem here, but somebody who's actually a Windows developer will need to spend time on it. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-05-01Document that subscription tests require hstorePeter Eisentraut
2018-04-30Does it help to wait before reattaching?Tom Lane
Revert the map/unmap dance I tried in commit 73042b8d1; that helps not at all. Instead, speculate that the unwanted allocation is being done on another thread, and thus timing variations explain the apparent unpredictability. Temporarily add a 1-second sleep before the VirtualFree call, in hopes that any such other threads will quiesce and not jog our elbow. This is obviously not a desirable long-term fix, but as a means of investigation it seems useful. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-30Map and unmap the shared memory block before risking VirtualFree.Tom Lane
The idea here is to get Windows' userspace infrastructure to allocate whatever space it needs for MapViewOfFileEx() before we release the locked-down space that we want to map the shared memory block into. This is a fairly brute-force attempt, and would likely (for example) fail with large shared memory on 32-bit Windows. We could perhaps ameliorate that by mapping only part of the shared memory block in this way, but for the moment I just want to see if this approach will fix dory's problem. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-30Further effort at preventing memory map dump from affecting the results.Tom Lane
Rather than elog'ing immediately, push the map data into a preallocated StringInfo. Perhaps this will prevent some of the mid-operation allocations that are evidently happening now. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-30Remove plperl isnan hackPeter Eisentraut
The code previously undefined isnan because of a compiler warning on MinGW. Since we now need to use isnan, we can't do that anymore. We might need a different solution if the compiler warning is too annoying.
2018-04-30Write error messages about duplicate OIDs to stderrPeter Eisentraut
2018-04-30Remove "Generating" output from catalog scriptsPeter Eisentraut
So by default, they don't output anything if everything is well. Discussion: https://www.postgresql.org/message-id/867f8a1a-6cf0-d835-78d8-0844e4936241%402ndquadrant.com
2018-04-30Don't do logical replication of TRUNCATE of zero tablesPeter Eisentraut
When due to publication configuration, a TRUNCATE change ends up with zero tables to be published, don't send the message out, just skip it. It's not wrong, but obviously useless overhead.
2018-04-30Remove Windows module-list-dumping code.Tom Lane
This code is evidently allocating memory and thus confusing matters even more. Let's see whether we can learn anything with just VirtualQuery. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-30clean up pg_upgrade tmp_check under MSVCAndrew Dunstan
2018-04-30Ignore file generated during pg_upgrade testingAndrew Dunstan
2018-04-30Dump full memory maps around failing Windows reattach code.Tom Lane
This morning's results from buildfarm member dory make it pretty clear that something is getting mapped into the just-freed space, but not what that something is. Replace my minimalistic probes with a full dump of the process address space and module space, based on Noah's work at <20170403065106.GA2624300%40tornado.leadboat.com> This is all (probably) to get reverted once we have fixed the problem, but for now we need information. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-29Fix bogus list-iteration code in pg_regress.c, affecting ecpg tests only.Tom Lane
While looking at a recent buildfarm failure in the ecpg tests, I wondered why the pg_regress output claimed the stderr part of the test failed, when the regression diffs were clearly for the stdout part. Looking into it, the reason is that pg_regress.c's logic for iterating over three parallel lists is wrong, and has been wrong since it was written: it advances the "tag" pointer at a different place in the loop than the other two pointers. Fix that.
2018-04-29Get still more info about Windows can't-reattach-to-shared-memory errors.Tom Lane
After some thought about the info captured so far, it seems possible that MapViewOfFileEx is itself causing some DLL to get loaded into the space just freed by VirtualFree. The previous commit here didn't capture enough info to really prove the case for that, so let's add one more VirtualQuery in between those steps. Also, be sure to capture the post-Map state before we emit any log entries, just in case elog() is invoking some code not previously loaded. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-29Avoid wrong results for power() with NaN input on more platforms.Tom Lane
Buildfarm results show that the modern POSIX rule that 1 ^ NaN = 1 is not honored on *BSD until relatively recently, and really old platforms don't believe that NaN ^ 0 = 1 either. (This is unsurprising, perhaps, since SUSv2 doesn't require either behavior.) In hopes of getting to platform independent behavior, let's deal with all the NaN-input cases explicitly in dpow(). Note that numeric_power() doesn't know either of these special cases. But since that behavior is platform-independent, I think it should be addressed separately, and probably not back-patched. Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
2018-04-29Get more info about Windows can't-reattach-to-shared-memory errors.Tom Lane
Commit 63ca350ef neglected to probe the state of things *before* the VirtualFree call, which now looks like it might be interesting. Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
2018-04-29Update time zone data files to tzdata release 2018d.Tom Lane
DST law changes in Palestine and Antarctica (Casey Station). Historical corrections for Portugal and its colonies, as well as Enderbury, Jamaica, Turks & Caicos Islands, and Uruguay.
2018-04-29Avoid wrong results for power() with NaN input on some platforms.Tom Lane
Per spec, the result of power() should be NaN if either input is NaN. It appears that on some versions of Windows, the libc function does return NaN, but it also sets errno = EDOM, confusing our code that attempts to work around shortcomings of other platforms. Hence, add guard tests to avoid substituting a wrong result for the right one. It's been like this for a long time (and the odd behavior only appears in older MSVC releases, too) so back-patch to all supported branches. Dang Minh Huong, reviewed by David Rowley Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp