release-9.2.sgml

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 <sect1 id="release-9-2-18">
  <title>Release 9.2.18</title>

  <note>
  <title>Release Date</title>
  <simpara>2016-08-11</simpara>
  </note>

  <para>
   This release contains a variety of fixes from 9.2.17.
   For information about new features in the 9.2 major release, see
   <xref linkend="release-9-2">.
  </para>

  <sect2>
   <title>Migration to Version 9.2.18</title>

   <para>
    A dump/restore is not required for those running 9.2.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.2.11,
    see <xref linkend="release-9-2-11">.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix corner-case misbehaviors for <literal>IS NULL</>/<literal>IS NOT
      NULL</> applied to nested composite values (Andrew Gierth, Tom Lane)
     </para>

     <para>
      The SQL standard specifies that <literal>IS NULL</> should return
      TRUE for a row of all null values (thus <literal>ROW(NULL,NULL) IS
      NULL</> yields TRUE), but this is not meant to apply recursively
      (thus <literal>ROW(NULL, ROW(NULL,NULL)) IS NULL</> yields FALSE).
      The core executor got this right, but certain planner optimizations
      treated the test as recursive (thus producing TRUE in both cases),
      and <filename>contrib/postgres_fdw</> could produce remote queries
      that misbehaved similarly.
     </para>
    </listitem>

    <listitem>
     <para>
      Make the <type>inet</> and <type>cidr</> data types properly reject
      IPv6 addresses with too many colon-separated fields (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent crash in <function>close_ps()</>
      (the <type>point</> <literal>##</> <type>lseg</> operator)
      for NaN input coordinates (Tom Lane)
     </para>

     <para>
      Make it return NULL instead of crashing.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unsafe intermediate state during expensive paths
      through <function>heap_update()</> (Masahiko Sawada, Andres Freund)
     </para>

     <para>
      Previously, these cases locked the target tuple (by setting its XMAX)
      but did not WAL-log that action, thus risking data integrity problems
      if the page were spilled to disk and then a database crash occurred
      before the tuple update could be completed.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid crash in <literal>postgres -C</> when the specified variable
      has a null string value (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid consuming a transaction ID during <command>VACUUM</>
      (Alexander Korotkov)
     </para>

     <para>
      Some cases in <command>VACUUM</> unnecessarily caused an XID to be
      assigned to the current transaction.  Normally this is negligible,
      but if one is up against the XID wraparound limit, consuming more
      XIDs during anti-wraparound vacuums is a very bad thing.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid canceling hot-standby queries during <command>VACUUM FREEZE</>
      (Simon Riggs, &Aacute;lvaro Herrera)
     </para>

     <para>
      <command>VACUUM FREEZE</> on an otherwise-idle master server could
      result in unnecessary cancellations of queries on its standby
      servers.
     </para>
    </listitem>

    <listitem>
     <para>
      When a manual <command>ANALYZE</> specifies a column list, don't
      reset the table's <literal>changes_since_analyze</> counter
      (Tom Lane)
     </para>

     <para>
      If we're only analyzing some columns, we should not prevent routine
      auto-analyze from happening for the other columns.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>ANALYZE</>'s overestimation of <literal>n_distinct</>
      for a unique or nearly-unique column with many null entries (Tom
      Lane)
     </para>

     <para>
      The nulls could get counted as though they were themselves distinct
      values, leading to serious planner misestimates in some types of
      queries.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent autovacuum from starting multiple workers for the same shared
      catalog (&Aacute;lvaro Herrera)
     </para>

     <para>
      Normally this isn't much of a problem because the vacuum doesn't take
      long anyway; but in the case of a severely bloated catalog, it could
      result in all but one worker uselessly waiting instead of doing
      useful work on other tables.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent infinite loop in GiST index build for geometric columns
      containing NaN component values (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <filename>contrib/btree_gin</> to handle the smallest
      possible <type>bigint</> value correctly (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Teach libpq to correctly decode server version from future servers
      (Peter Eisentraut)
     </para>

     <para>
      It's planned to switch to two-part instead of three-part server
      version numbers for releases after 9.6.  Make sure
      that <function>PQserverVersion()</> returns the correct value for
      such cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</>'s code for <literal>unsigned long long</>
      array elements (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</> with both <option>-c</> and <option>-C</>
      options, avoid emitting an unwanted <literal>CREATE SCHEMA public</>
      command (David Johnston, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_basebackup</> accept <literal>-Z 0</> as
      specifying no compression (Fujii Masao)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix makefiles' rule for building AIX shared libraries to be safe for
      parallel make (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix TAP tests and MSVC scripts to work when build directory's path
      name contains spaces (Michael Paquier, Kyotaro Horiguchi)
     </para>
    </listitem>

    <listitem>
     <para>
      Make regression tests safe for Danish and Welsh locales (Jeff Janes,
      Tom Lane)
     </para>

     <para>
      Change some test data that triggered the unusual sorting rules of
      these locales.
     </para>
    </listitem>

    <listitem>
     <para>
      Update our copy of the timezone code to match
      IANA's <application>tzcode</> release 2016c (Tom Lane)
     </para>

     <para>
      This is needed to cope with anticipated future changes in the time
      zone data files.  It also fixes some corner-case bugs in coping with
      unusual time zones.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</> release 2016f
      for DST law changes in Kemerovo and Novosibirsk, plus historical
      corrections for Azerbaijan, Belarus, and Morocco.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-2-17">
  <title>Release 9.2.17</title>

  <note>
  <title>Release Date</title>
  <simpara>2016-05-12</simpara>
  </note>

  <para>
   This release contains a variety of fixes from 9.2.16.
   For information about new features in the 9.2 major release, see
   <xref linkend="release-9-2">.
  </para>

  <sect2>
   <title>Migration to Version 9.2.17</title>

   <para>
    A dump/restore is not required for those running 9.2.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.2.11,
    see <xref linkend="release-9-2-11">.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Clear the OpenSSL error queue before OpenSSL calls, rather than
      assuming it's clear already; and make sure we leave it clear
      afterwards (Peter Geoghegan, Dave Vitek, Peter Eisentraut)
     </para>

     <para>
      This change prevents problems when there are multiple connections
      using OpenSSL within a single process and not all the code involved
      follows the same rules for when to clear the error queue.
      Failures have been reported specifically when a client application
      uses SSL connections in <application>libpq</> concurrently with
      SSL connections using the PHP, Python, or Ruby wrappers for OpenSSL.
      It's possible for similar problems to arise within the server as well,
      if an extension module establishes an outgoing SSL connection.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>failed to build any <replaceable>N</>-way joins</quote>
      planner error with a full join enclosed in the right-hand side of a
      left join (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect handling of equivalence-class tests in multilevel
      nestloop plans (Tom Lane)
     </para>

     <para>
      Given a three-or-more-way equivalence class of variables, such
      as <literal>X.X = Y.Y = Z.Z</>, it was possible for the planner to omit
      some of the tests needed to enforce that all the variables are actually
      equal, leading to join rows being output that didn't satisfy
      the <literal>WHERE</> clauses.  For various reasons, erroneous plans
      were seldom selected in practice, so that this bug has gone undetected
      for a long time.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible misbehavior of <literal>TH</>, <literal>th</>,
      and <literal>Y,YYY</> format codes in <function>to_timestamp()</>
      (Tom Lane)
     </para>

     <para>
      These could advance off the end of the input string, causing subsequent
      format codes to read garbage.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of rules and views in which the <replaceable>array</>
      argument of a <literal><replaceable>value</> <replaceable>operator</>
      ANY (<replaceable>array</>)</literal> construct is a sub-SELECT
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_regress</> use a startup timeout from the
      <envar>PGCTLTIMEOUT</> environment variable, if that's set (Tom Lane)
     </para>

     <para>
      This is for consistency with a behavior recently added
      to <application>pg_ctl</>; it eases automated testing on slow machines.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</> to correctly restore extension
      membership for operator families containing only one operator class
      (Tom Lane)
     </para>

     <para>
      In such a case, the operator family was restored into the new database,
      but it was no longer marked as part of the extension.  This had no
      immediate ill effects, but would cause later <application>pg_dump</>
      runs to emit output that would cause (harmless) errors on restore.
     </para>
    </listitem>

    <listitem>
     <para>
      Back-port 9.4-era memory-barrier code changes into 9.2 and 9.3 (Tom Lane)
     </para>

     <para>
      These changes were not originally needed in pre-9.4 branches, but we
      recently back-patched a fix that expected the barrier code to work
      properly.  Only IA64 (when using icc), HPPA, and Alpha platforms are
      affected.
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce the number of SysV semaphores used by a build configured with
      <option>--disable-spinlocks</> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Rename internal function <function>strtoi()</>
      to <function>strtoint()</> to avoid conflict with a NetBSD library
      function (Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix reporting of errors from <function>bind()</>
      and <function>listen()</> system calls on Windows (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce verbosity of compiler output when building with Microsoft Visual
      Studio (Christian Ullrich)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possibly-unsafe use of Windows' <function>FormatMessage()</>
      function (Christian Ullrich)
     </para>

     <para>
      Use the <literal>FORMAT_MESSAGE_IGNORE_INSERTS</> flag where
      appropriate.  No live bug is known to exist here, but it seems like a
      good idea to be careful.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</> release 2016d
      for DST law changes in Russia and Venezuela.  There are new zone
      names <literal>Europe/Kirov</> and <literal>Asia/Tomsk</> to reflect
      the fact that these regions now have different time zone histories from
      adjacent regions.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-2-16">
  <title>Release 9.2.16</title>

  <note>
  <title>Release Date</title>
  <simpara>2016-03-31</simpara>
  </note>

  <para>
   This release contains a variety of fixes from 9.2.15.
   For information about new features in the 9.2 major release, see
   <xref linkend="release-9-2">.
  </para>

  <sect2>
   <title>Migration to Version 9.2.16</title>

   <para>
    A dump/restore is not required for those running 9.2.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.2.11,
    see <xref linkend="release-9-2-11">.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix incorrect handling of NULL index entries in
      indexed <literal>ROW()</> comparisons (Tom Lane)
     </para>

     <para>
      An index search using a row comparison such as <literal>ROW(a, b) &gt;
      ROW('x', 'y')</> would stop upon reaching a NULL entry in
      the <structfield>b</> column, ignoring the fact that there might be
      non-NULL <structfield>b</> values associated with later values
      of <structfield>a</>.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unlikely data-loss scenarios due to renaming files without
      adequate <function>fsync()</> calls before and after (Michael Paquier,
      Tomas Vondra, Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Correctly handle cases where <literal>pg_subtrans</> is close to XID
      wraparound during server startup (Jeff Janes)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix corner-case crash due to trying to free <function>localeconv()</>
      output strings more than once (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix parsing of affix files for <literal>ispell</> dictionaries
      (Tom Lane)
     </para>

     <para>
      The code could go wrong if the affix file contained any characters
      whose byte length changes during case-folding, for
      example <literal>I</> in Turkish UTF8 locales.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid use of <function>sscanf()</> to parse <literal>ispell</>
      dictionary files (Artur Zakirov)
     </para>

     <para>
      This dodges a portability problem on FreeBSD-derived platforms
      (including OS X).
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid a crash on old Windows versions (before 7SP1/2008R2SP1) with an
      AVX2-capable CPU and a Postgres build done with Visual Studio 2013
      (Christian Ullrich)
     </para>

     <para>
      This is a workaround for a bug in Visual Studio 2013's runtime
      library, which Microsoft have stated they will not fix in that
      version.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</>'s tab completion logic to handle multibyte
      characters properly (Kyotaro Horiguchi, Robert Haas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</>'s tab completion for
      <literal>SECURITY LABEL</> (Tom Lane)
     </para>

     <para>
      Pressing TAB after <literal>SECURITY LABEL</> might cause a crash
      or offering of inappropriate keywords.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_ctl</> accept a wait timeout from the
      <envar>PGCTLTIMEOUT</> environment variable, if none is specified on
      the command line (Noah Misch)
     </para>

     <para>
      This eases testing of slower buildfarm members by allowing them
      to globally specify a longer-than-normal timeout for postmaster
      startup and shutdown.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect test for Windows service status
      in <application>pg_ctl</> (Manuel Mathar)
     </para>

     <para>
      The previous set of minor releases attempted to
      fix <application>pg_ctl</> to properly determine whether to send log
      messages to Window's Event Log, but got the test backwards.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pgbench</> to correctly handle the combination
      of <literal>-C</> and <literal>-M prepared</> options (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In PL/Perl, properly translate empty Postgres arrays into empty Perl
      arrays (Alex Hunsaker)
     </para>
    </listitem>

    <listitem>
     <para>
      Make PL/Python cope with function names that aren't valid Python
      identifiers (Jim Nasby)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix multiple mistakes in the statistics returned
      by <filename>contrib/pgstattuple</>'s <function>pgstatindex()</>
      function (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Remove dependency on <literal>psed</> in MSVC builds, since it's no
      longer provided by core Perl (Michael Paquier, Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</> release 2016c
      for DST law changes in Azerbaijan, Chile, Haiti, Palestine, and Russia
      (Altai, Astrakhan, Kirov, Sakhalin, Ulyanovsk regions), plus
      historical corrections for Lithuania, Moldova, and Russia
      (Kaliningrad, Samara, Volgograd).
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-2-15">
  <title>Release 9.2.15</title>

  <note>
  <title>Release Date</title>
  <simpara>2016-02-11</simpara>
  </note>

  <para>
   This release contains a variety of fixes from 9.2.14.
   For information about new features in the 9.2 major release, see
   <xref linkend="release-9-2">.
  </para>

  <sect2>
   <title>Migration to Version 9.2.15</title>

   <para>
    A dump/restore is not required for those running 9.2.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.2.11,
    see <xref linkend="release-9-2-11">.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix infinite loops and buffer-overrun problems in regular expressions
      (Tom Lane)
     </para>

     <para>
      Very large character ranges in bracket expressions could cause
      infinite loops in some cases, and memory overwrites in other cases.
      (CVE-2016-0773)
     </para>
    </listitem>

    <listitem>
     <para>
      Perform an immediate shutdown if the <filename>postmaster.pid</> file
      is removed (Tom Lane)
     </para>

     <para>
      The postmaster now checks every minute or so
      that <filename>postmaster.pid</> is still there and still contains its
      own PID.  If not, it performs an immediate shutdown, as though it had
      received <systemitem>SIGQUIT</>.  The main motivation for this change
      is to ensure that failed buildfarm runs will get cleaned up without
      manual intervention; but it also serves to limit the bad effects if a
      DBA forcibly removes <filename>postmaster.pid</> and then starts a new
      postmaster.
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>SERIALIZABLE</> transaction isolation mode, serialization
      anomalies could be missed due to race conditions during insertions
      (Kevin Grittner, Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix failure to emit appropriate WAL records when doing <literal>ALTER
      TABLE ... SET TABLESPACE</> for unlogged relations (Michael Paquier,
      Andres Freund)
     </para>

     <para>
      Even though the relation's data is unlogged, the move must be logged or
      the relation will be inaccessible after a standby is promoted to master.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible misinitialization of unlogged relations at the end of
      crash recovery (Andres Freund, Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>ALTER COLUMN TYPE</> to reconstruct inherited check
      constraints properly (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</> to change ownership of composite types
      properly (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</> and <command>ALTER OWNER</> to correctly
      update granted-permissions lists when changing owners of data types,
      foreign data wrappers, or foreign servers (Bruce Momjian,
      &Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</> to ignore foreign user mappings,
      rather than fail (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Add more defenses against bad planner cost estimates for GIN index
      scans when the index's internal statistics are very out-of-date
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make planner cope with hypothetical GIN indexes suggested by an index
      advisor plug-in (Julien Rouhaud)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of whole-row Vars in <literal>ROW()</>
      and <literal>VALUES()</> lists (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible internal overflow in <type>numeric</> division
      (Dean Rasheed)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix enforcement of restrictions inside parentheses within regular
      expression lookahead constraints (Tom Lane)
     </para>

     <para>
      Lookahead constraints aren't allowed to contain backrefs, and
      parentheses within them are always considered non-capturing, according
      to the manual.  However, the code failed to handle these cases properly
      inside a parenthesized subexpression, and would give unexpected
      results.
     </para>
    </listitem>

    <listitem>
     <para>
      Conversion of regular expressions to indexscan bounds could produce
      incorrect bounds from regexps containing lookahead constraints
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix regular-expression compiler to handle loops of constraint arcs
      (Tom Lane)
     </para>

     <para>
      The code added for CVE-2007-4772 was both incomplete, in that it didn't
      handle loops involving more than one state, and incorrect, in that it
      could cause assertion failures (though there seem to be no bad
      consequences of that in a non-assert build).  Multi-state loops would
      cause the compiler to run until the query was canceled or it reached
      the too-many-states error condition.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve memory-usage accounting in regular-expression compiler
      (Tom Lane)
     </para>

     <para>
      This causes the code to emit <quote>regular expression is too
      complex</> errors in some cases that previously used unreasonable
      amounts of time and memory.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve performance of regular-expression compiler (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <literal>%h</> and <literal>%r</> escapes
      in <varname>log_line_prefix</> work for messages emitted due
      to <varname>log_connections</> (Tom Lane)
     </para>

     <para>
      Previously, <literal>%h</>/<literal>%r</> started to work just after a
      new session had emitted the <quote>connection received</> log message;
      now they work for that message too.
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, ensure the shared-memory mapping handle gets closed in
      child processes that don't need it (Tom Lane, Amit Kapila)
     </para>

     <para>
      This oversight resulted in failure to recover from crashes
      whenever <varname>logging_collector</> is turned on.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible failure to detect socket EOF in non-blocking mode on
      Windows (Tom Lane)
     </para>

     <para>
      It's not entirely clear whether this problem can happen in pre-9.5
      branches, but if it did, the symptom would be that a walsender process
      would wait indefinitely rather than noticing a loss of connection.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid leaking a token handle during SSPI authentication
      (Christian Ullrich)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>psql</>, ensure that <application>libreadline</>'s idea
      of the screen size is updated when the terminal window size changes
      (Merlin Moncure)
     </para>

     <para>
      Previously, <application>libreadline</> did not notice if the window
      was resized during query output, leading to strange behavior during
      later input of multiline queries.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</>'s <literal>\det</> command to interpret its
      pattern argument the same way as other <literal>\d</> commands with
      potentially schema-qualified patterns do (Reece Hart)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possible crash in <application>psql</>'s <literal>\c</> command
      when previous connection was via Unix socket and command specifies a
      new hostname and same username (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>pg_ctl start -w</>, test child process status directly
      rather than relying on heuristics (Tom Lane, Michael Paquier)
     </para>

     <para>
      Previously, <application>pg_ctl</> relied on an assumption that the new
      postmaster would always create <filename>postmaster.pid</> within five
      seconds.  But that can fail on heavily-loaded systems,
      causing <application>pg_ctl</> to report incorrectly that the
      postmaster failed to start.
     </para>

     <para>
      Except on Windows, this change also means that a <literal>pg_ctl start
      -w</> done immediately after another such command will now reliably
      fail, whereas previously it would report success if done within two
      seconds of the first command.
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>pg_ctl start -w</>, don't attempt to use a wildcard listen
      address to connect to the postmaster (Kondo Yuta)
     </para>

     <para>
      On Windows, <application>pg_ctl</> would fail to detect postmaster
      startup if <varname>listen_addresses</> is set to <literal>0.0.0.0</>
      or <literal>::</>, because it would try to use that value verbatim as
      the address to connect to, which doesn't work.  Instead assume
      that <literal>127.0.0.1</> or <literal>::1</>, respectively, is the
      right thing to use.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_ctl</> on Windows, check service status to decide
      where to send output, rather than checking if standard output is a
      terminal (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</> and <application>pg_basebackup</>, adopt