In pg_upgrade, remove dependency on pg_config, as that might not be in
the non-development install.  Instead, use the LOAD mechanism to check
for the pg_upgrade_support shared object, like we do for other shared
object checks.

Backpatch to 9.1.

Report from Àlvaro
plperl: Package-qualify _TD

Failing to do so causes trigger invocation to fail when they are nested
within a function invocation that changes the current package.

Backpatch to 9.1; previous releases used a different method to obtain
_TD.  Per bug report from Mark Murawski (bug #6511)

Author: Alex Hunsaker
pg_dump: fix double free of query results

This bug was introduced while refactoring in commit 1631598e --- no need
to back-patch.

Bug report and fix from Joachim Wieland.
Restructure SELECT INTO's parsetree representation into CreateTableAsStmt.

Making this operation look like a utility statement seems generally a good
idea, and particularly so in light of the desire to provide command
triggers for utility statements.  The original choice of representing it as
SELECT with an IntoClause appendage had metastasized into rather a lot of
places, unfortunately, so that this patch is a great deal more complicated
than one might at first expect.

In particular, keeping EXPLAIN working for SELECT INTO and CREATE TABLE AS
subcommands required restructuring some EXPLAIN-related APIs.  Add-on code
that calls ExplainOnePlan or ExplainOneUtility, or uses
ExplainOneQuery_hook, will need adjustment.

Also, the cases PREPARE ... SELECT INTO and CREATE RULE ... SELECT INTO,
which formerly were accepted though undocumented, are no longer accepted.
The PREPARE case can be replaced with use of CREATE TABLE AS EXECUTE.
The CREATE RULE case doesn't seem to have much real-world use (since the
rule would work only once before failing with "table already exists"),
so we'll not bother with that one.

Both SELECT INTO and CREATE TABLE AS still return a command tag of
"SELECT nnnn".  There was some discussion of returning "CREATE TABLE nnnn",
but for the moment backwards compatibility wins the day.

Andres Freund and Tom Lane
pg_dump: Remove undocumented "files" output format

This was for demonstration only, and now it was creating compiler
warnings from zlib without an obvious fix (see also
d923125b77c5d698bb8107a533a21627582baa43), let's just remove it.  The
"directory" format is presumably similar enough anyway.
pg_upgrade: Add new generated file to .gitignore
Remove stray word from sepgsql documentation.
Update struct Trigger in docs
Fix trigger example code to match header changes

I should have done this in b93f5a5673b4bb09e14eb80fe28aa21fc20a6271 but
didn't notice the problem at the time.

Per report from Marco Nenciarini
pg_dump: get rid of die_horribly

The old code was using exit_horribly or die_horribly other depending on
whether it had an ArchiveHandle on which to close the connection or not;
but there were places that were passing a NULL ArchiveHandle to
die_horribly, and other places that used exit_horribly while having an
AH available.  So there wasn't all that much consistency.

Improve the situation by keeping only one of the routines, and instead
of having to pass the AH down from the caller, arrange for it to be
present for an on_exit_nicely callback to operate on.

Author: Joachim Wieland
Some tweaks by me

Per a suggestion from Robert Haas, in the ongoing "parallel pg_dump"
saga.
Improve the -l (limit) option recently added to contrib/vacuumlo.

Instead of just stopping after removing an arbitrary subset of orphaned
large objects, commit and start a new transaction after each -l objects.
This is just as effective as the original patch at limiting the number of
locks used, and it doesn't require doing the OID collection process
repeatedly to get everything.  Since the option no longer changes the
fundamental behavior of vacuumlo, and it avoids a known server-side
limitation, enable it by default (with a default limit of 1000 LOs per
transaction).

In passing, be more careful about properly quoting the names of tables
and fields, and do some other cosmetic cleanup.
Add some CHECK_FOR_INTERRUPTS() calls to the heap-sort call path.

I broke this in commit 337b6f5ecf05b21b5e997986884d097d60e4e3d0, which
among other things arranged for quicksorts to CHECK_FOR_INTERRUPTS()
slightly less frequently.  Sadly, it also arranged for heapsorts to
CHECK_FOR_INTERRUPTS() much less frequently.  Repair.
Improve connectMaintenanceDatabase() error reporting.

The prior coding instructs the user to pick an alternative maintenance
database, but this is overly clever, since it obscures whatever the real
cause of the failure is.

Josh Kupershmidt
Allow new relmapper entries when allow_system_table_mods is true.

This restores the pre-9.0 situation that it's possible to add new indexes
on pg_class and other mapped-but-not-shared catalogs, so long as you broke
the glass and flipped the big red Dont-Touch-Me switch.  As before, there
are a lot of gotchas, and you'd have to be pretty desperate to try this
on a production database; but there doesn't seem to be a reason for
relmapper.c to be preventing such things all by itself.  Per
experimentation with a case suggested by Cody Cutrer.
Doc updates for index-only scans.

Document that routine vacuuming is now also important for the purpose
of index-only scans; and mention in the section that describes the
visibility map that it is used to implement index-only scans.

Marti Raudsepp, with some changes by me.
Add installing entab to pgindent instructions

And minor other pgindent documentation tweaks.
Clean up compiler warnings from unused variables with asserts disabled

For those variables only used when asserts are enabled, use a new
macro PG_USED_FOR_ASSERTS_ONLY, which expands to
__attribute__((unused)) when asserts are not enabled.
Fix configure's search for collateindex.pl.

PGAC_PATH_COLLATEINDEX supposed that it could use AC_PATH_PROGS to search
for collateindex.pl, but that macro will only accept files that are marked
executable, and at least some DocBook installations don't mark the script
executable (a case the docs Makefile was already prepared for).  Accept the
script if it's present and readable in $DOCBOOKSTYLE/bin, and otherwise
search the PATH as before.

Having fixed that up, we don't need the fallback case that was in the docs
Makefile, and instead can throw an understandable error if configure didn't
find the script.  Per recent trouble report from John Lumby.
If a role has a password expiration date, show that in psql's \du output.

Per a suggestion from Euler Taveira, it seems like a good idea to include
this information in \du (and \dg) output.  This costs nothing for people
who are not using the VALID UNTIL feature, while for those who are, it's
rather critical information.

Fabrízio de Royes Mello
Refactor to eliminate duplicate copies of conninfo default-finding code.

Alex Shulgin, lightly edited by me