Log message:
Update to 1.4.17. From the changelog:

API:

* Database::get_average_length(): Add this as an alias for Database::get_avlen().
  In git master we've added this as a preferred new name - adding it to 1.4.x too
  will make it easier for users to update to using this.

* Database::get_spelling_suggestion(): Optimise edit distance initialisation
  loop to significantly reduce the cost of a typical edit distance calculation.

* Fix query expansion on sharded databases.  The mechanism for passing in which
  shard a TermList is from wasn't hooked up and as a result we'd always think
  it's from the first shard, meaning the statistics would be wrong and that our
  suggested terms may not have been as good as they should be in this
  situation.

* Enquire::get_eset(): Use string::compare() to avoid 1/3 of the string compares
  on average.

documentation:

* Update doxygen HTML headers and footers to resolve issues with some
  interactive features of the API docs not working.  Reported by Enrico Zini.

* Stop specifying obsolete doxygen settings PERL_PATH and MSCGEN_PATH.

* Clarify API docs for MSet::get_termfreq() to make it clear that this
  considers all documents in the database, not only those that matched the
  searched (it would sometimes be useful to be able to report the number of
  occurrences of a term in the matched documents, but it's not something we
  currently keep track of).  Reported by Tadeusz Sośnierz and Peter Salomonsen.

Log message:
Update to 1.4.16. From the changelog:

API:

* MSet::snippet(): The snippet now includes trailing punctuation which carries
  meaning or gives useful context.  See
  https://github.com/xapian/xapian/pull/180, reported by Robert Stepanek.

* MSet::snippet(): Fix segfault generating snippet from default-constructed
  MSet.  This probably isn't something you'd typically do, but it shouldn't
  crash.  Found during extended testing of #803 (which only affected git
  master) which was reported by Robert Stepanek.

* Remove trailing full stop from exception messages.  We conventionally don't
  include one, but a few cases didn't follow that convention.

testsuite:

* Replace direct use of ftime() which gives deprecation warnings with recent
  mingw.  Reported by srinivasyadav22.

matcher:

* Fix segfault in rare cases in the query optimiser.  We keep a pointer to the
  most recent posting list to use as a hint for opening the next posting list,
  but the existing mechanism to take ownership of this hint had a flaw.  We now
  invalidate the hint in situations where it might be indirectly deleted which
  is safe, but somewhat conservative.

* Improve the optimisation of an always-matching OP_VALUE_GE to also take
  effect when the value slot's lower bound is equal to the limit of the
  OP_VALUE_GE.  Patch from boda sadalla.

glass backend:

* Report the correct errno value if commit() fails.  We were potentially
  reporting ENOENT from an unlink() call cleaning up a temporary file prior to
  throwing the exception instead.

documentation:

* Fix missing menus in API documentation.  Newer doxygen generates .js files
  which we also need to distribute and install.  Reported by sec^nd on #xapian.

* Note OP_FILTER ignored subquery bug fixed in 1.4.15 as present in 1.4.14 and
  older.

portability:

* Use our own autoconf cache variable namespace (xo_cv_ prefix instead of
  ac_cv_) to avoid colliding with standard autoconf macro use if config.site or
  a shared config.cache is used.  The former case caused a build failure for
  the OpenBSD port with 1.4.15, reported by Lucas R.

* Use clock_gettime() and nanosleep() under modern mingw as these allow higher
  precision than what we previously used.

Bindings:

* Remove code to support SVN snapshots since we stopped using SVN more than 5
  years ago.

* Ignore overloads for logical ops, *, /.  These were already ignored for
  several languages, and aren't actually usefully wrapped for any of the other
  languages.

CSharp:

* Work around mono terminfo parsing bug in more cases.  With this, "make",
  "make check", "make install" and "make \ 
uninstall" all work on Ubuntu 18.10.
  Patch from Dipanshu Garg, fixes https://github.com/xapian/xapian/pull/287 and
  #801.

Lua:

* Allow passing a Lua function as a MatchSpy.  This was supposed to be
  supported already, but the typemaps weren't set up.

* On platforms where sizeof(long) is 4, SWIG was wrapping Xapian::BAD_VALUENO
  as a negative constant in Lua, which was then rejected by a check which
  disallows passing negative values for unsigned C++ types.  We now direct SWIG
  to handle Xapian::valueno as double (which is what numbers in Lua usually
  actually are) which gives us an unsigned constant, and also eliminates the
  negative value check.

* Correct documentation - get_description() is wrapped as tostring() in Lua,
  not str() as we previously claimed.

* Add test coverage for passing Lua function for a Stopper.

Perl:

* Resolve the remaining issues and remove the "experimental" marker:

  + Add search_xapian_compat() function which sets up aliases in the
    Search::Xapian namespace to aid writing code which uses either
    Search::Xapian or this module.

  + Allow passing Perl sub for simpler Xapian functor classes.  This fills in a
    missing feature compared to Search::Xapian.  See #523.

  + Remove useless PerlStopper class which was an incomplete copy of the
    apparently non-functional Search::Xapian::PerlStopper.  We now support
    passing a Perl sub for a Stopper object.

  + Adjust some method names to match Search::Xapian.  Iterators now support
    inc() (and dec() where the C++ class supports operator--) like
    Search::Xapian, rather than increment() and prev().  Reported by Eric Wong
    in #523.

  + Drop undocumented and unexpected extra equals() method.

  + Provide compatibility with ENQ_ASCENDING, etc constants.  SWIG wraps these
    as $Xapian::Enquire::ASCENDING, which better matches the C++ API, but
    Search::Xapian wraps this as Search::Xapian::ENQ_ASCENDING, etc so provide
    those too for compatibility.  Reported by Eric Wong in #523.

  + Drop stringification and int conversion overloads.  These seem more
    confusing than helpful, and overloading stringification works badly
    with SWIG-generated bindings.

  + Document remaining known differences from Search::Xapian.

* Update recently tested versions in README.

* Improve documentation.

* Fix t/02pod.t to look for files in right directory.

Ruby:

* Don't print iterator sizes to stdout.  This was some debugging accidentally
  left in as part of a change in 1.4.12.  Patch from Dan Callaghan.

Log message:
Update to 1.4.15. From the changelog:

API:

* Database::check(): Fix checking of replication changesets.  This reverts a
  change incorrectly made in 1.3.7.

* Database::locked(): Return false instead of true for a closed inmemory DB.

* Database::commit(): If commit() failed with an exception while trying to add
  pending changes (e.g. InvalidArgumentError due to a long term containing zero
  bytes) then a subsequent commit() on the same object would throw the same
  exception.  Now we clear the pending changes in this situation (like we
  already did for failure at other stages in the commit).  This bug remains
  unfixed for the chert backend as it's harder to fix there and the effort to
  fix it and extra risk of breakage don't seem justified for a backend we
  recommend people migrate away from.

* QueryParser::parse_query(): Optimise parsing of multi-word synonyms.

testsuite:

* Use 50-word synonym for qp_scale1 "large" case.  50 divides exactly \ 
into the
  number of repetitions we do for the "small" case, which 60 (as used \ 
before)
  doesn't.  This makes the two cases a little more comparable and should help
  make this testcase less flaky (see #764).

* Adjust testcase matches1 to work with remote shards where the matcher can
  return slightly better bounds on the number of matches in some cases.
  Resolves 2 XFAILs.

* The testharness get_remote_database() method is now supported for sharded
  databases.  This is needed for keepalive1 to run successfully under multi
  test backends.  Resolves 2 XFAILs of keepalive1.

* Improved test coverage:

  + Test locked() on a closed WritableDatabase, which already returns false (as
    expected) in 1.4.x (but was broken on master).

  + Check multi databases in testsuite - this has been supported by
    Database::check() since 1.4.12.

  + Also test OP_SYNONYM and OP_MAX in emptydb1.

  + Backport testcases boolorbug1, emptynot1, emptymaybe1 and
    phraseweightcheckbug1 from git master - these are regression tests for
    fixed bugs which only affected git master, but it's useful to confirm that
    these bugs don't currently affect 1.4, and ensure they don't get introduced.

* perftest: Store memory sizes as long long since on Microsoft Windows long is
  only 32 bits, which is less than common memory sizes.

matcher:

* Hoist positional check above OP_FILTER.

* Handle OP_FILTER with more than two subqueries correctly.  Previously we'd
  only check the first two subqueries in some situations.

remote backend:

* For a remote WritableDatabase, the client now keeps track of whether there
  are pending changes, and if there aren't then we now do nothing for commit()
  or cancel() calls.  In particular this saves a message exchange when the
  WritableDatabase destructor is called when changes have already been
  committed with an explicit call to commit() (which is what we recommend
  doing, since with an explicit call to commit() you get to see any exception
  which gets thrown).

* When closing a remote prog WritableDatabase, previously an exception could
  leave the remote connection open with the remote server running, and we'd
  then wait for the specified timeout before closing the connection.  Now we
  close the connection before letting the exception propagate.

* Don't swallow exceptions from Database::close() on a remote database.  If
  we aren't in a transaction and so try to commit() and that fails then
  previously the caller would have no indication of the failure.

* Fix handling the reported term weight when remote shards are searched.
  Fixes 5 XFAILs in the testsuite.

* Add missing space to mismatching protocol versions error message.

build system:

* Fix to build when configured with --disable-backend-remote, broken by changes
  in 1.4.14.  Fixes #797, reported by Дилян Палаузов.

* The clang and icc compilers both define __GNUC__, which led our ABI mismatch
  message to report them as "g++" with a bogus version (the version of \ 
GCC that
  these compilers advertise themselves as, which for clang is always 4.2.0) -
  now we report clang++ or icc along with the actual version of that compiler.

documentation:

* AUTHORS: Apply missed update to the thankyou list for 1.4.14.

* INSTALL: Note that MSVC 2019 works.

* INSTALL: Note that Xapian can use the system uuid.h on AIX and OpenBSD.

portability:

* Simplify probes for snprintf.  The broken snprintf in libbsd in Linux libc4
  is from ~25 years ago so way too ancient to matter now, and all callers
  already handle the pre-ISO semantics of returning -1 for an undersize buffer
  so we don't need to run a test program to probe for this at configure time,
  which is more cross-compile friendly.

* Don't quote messages in #error - the quotes aren't required and appear in the
  compiler output (at least with GCC and clang) making it less readable.

* Use a different approach for getting a 64-bit capable stat() for mingw32.
  This means we now use the same stat variant for mingw32 and MSVC, which
  seems a better plan.

* Work around unhelpful config.status behaviour.  It comments out any #undef
  lines in config.h, even those added via AH_TOP and AH_BOTTOM.  Splitting
  these lines means they don't match the regex hammer config.status uses.

* Avoid -Wdeprecated-copy warnings from clang 10.

* Avoid deprecation warning on recent Linux.  We were including sys/sysctl.h if
  it existed, which it does on Linux but we don't actually use it there.
  Including it now warns that it is deprecated, so skip including it under
  Linux.  Reported on IRC by kumaran.

* Suppress GCC -Wduplicated-branches warning from our API headers in a
  different way which avoids needing a compiler-specific #pragma.

* Workaround closefrom1 failure on macOS.  It seems under macOS our fd tracking
  can end up using fd 10 so start from 13 when testing closefrom() so we don't
  close the fd which our fd tracking is using internally.

debug code:

* Log RemoteConnection::read_at_least() return value.

Log message:
Add missing errno.h

Log message:
Update to 1.4.14. From the changelog:

API:

* Xapian::QueryParser: Handle "" inside a quoted phrase better.  In a \ 
quoted
  boolean term, "" is treated as an escaped ", so handle it in a \ 
compatible way
  for quoted phrases.  Previously we'd drop out of the phrase and start a new
  phrase.  Fixes #630, reported by Austin Clements.

* Xapian::Stem: The constructor which takes a stemmer name now takes an
  optional second bool parameter - if this is true, then an unknown stemmer
  name falls back to using the "none" stemmer instead of throwing an \ 
exception.
  This allows simply constructing a stemmer from an ISO language code without
  having to worry about whether there's a stemmer for that language, and
  without having to handle an exception if there isn't.

* Xapian::Stem: Fix a bug with handling 4-byte UTF-8 sequences which
  potentially affects most of the stemmers.  None of the stemmers work in
  languages where 4-byte UTF-8 sequences are part of the alphabet, but this
  bug could result in invalid UTF-8 sequences in terms generated from text
  containing high Unicode codepoints such as emoji, which can cause issues (for
  example, in some language bindings).  Fix synced from Snowball git post
  2.0.0.  Reported by Ilari Nieminen in
  https://github.com/snowballstem/snowball/issues/89.

* Xapian::Stem: Add a new is_none() method which tests if this is a "none"
  stemmer.

* Xapian::Weight: The total length of all documents is now made available to
  Xapian::Weight subclasses, and this is now used by DLHWeight, DPHWeight and
  LMWeight.  To maintain ABI compatibility, internally this still fetches the
  average length and the number of documents, multiplies them, then rounds the
  result, but in the next release series this will be handled directly.

* Xapian::Database::locked() on an inmemory database used to always return
  false, but an inmemory Database is always actually a WritableDatabase
  underneath, so now we always report true in this case because it's really
  always report being locked for writing.

* Fix write one past end of std::vector on certain QueryParser parser errors.
  This is undefined behaviour, but the write was always into reserved space, so
  in practice we'd actually get away with it (it was noticed because it
  triggers an error when running under ubsan and using libc++).  Reported by
  Germán M. Bravo.

* MSet::get_matches_estimated(): Improve rounding of result - a bug meant we
  would almost always round down.

* Optimise test for UTF-8 continuation character.  Performing a signed char
  comparison shaves an instruction or two on most architectures.

* Database::get_revision(): Return revision 0 for a Database with no shards
  rather that throwing InvalidOperationError.

* DPHWeight: Avoid dividing by 0 when searching a sharded database when one
  shard is empty.  The result wasn't used in this case, but it's still
  undefined behaviour.  Detected by UBSan.

testsuite:

* Fix failing multi_glass_remoteprog_glass tests on x86.  When the tests are
  run under valgrind, remote servers should be run using the runsrv wrapper
  script, but this wasn't happening for remote servers in multi-databases - now
  it is.  Also, previously runsrv only used valgrind for the remote for an x86
  build that didn't use SSE, but it seems there are x87 instructions in libc
  that are affected by valgrind not providing excess precision, so do this for
  x86 builds which use SSE too.  Together these changes fix failures of
  topercent2, xor2, tradweight1 under backend multi_glass_remoteprog_glass on
  x86.

* Fix C++ One-Definition Rule (ODR) violation in testsuite code.  Two different
  source files linked into apitest were each defining a different `struct
  test`.  Wrap each in an anonymous namespace to localise it to the file it is
  defined and used in.  This was probably harmless in practice, unless trying
  to build with Link-Time Optimisation or similar (which is how it was
  detected).

* Test all language codes in stemlangs1.  The testsuite hardcodes a list of
  supported language codes which hadn't been updated since 2008.

* Improve DateRangeProcessor test coverage.

* The "singlefile" test harness backend manager now creates databases by
  compacting the corresponding underlying backend database (creating it first
  if need be) rather than always creating a temporary database to compact.

* Enable compaction testcases for multi and singlefile test harness backends.

* Add generated database support for remoteprog and remotetcp test harness
  backends.  Implemented by Tanmay Sachan.

* Add test harness support for running testcases using a multi database
  comprised of one local and one remote shard, or two remote shards.
  Implemented by Tanmay Sachan.

* Check if removing existing multi stub failed.  Previously if removing an
  existing stub failed, the test harness would create a temporary new stub and
  then try to rename it over the old one, which will always fail on Microsoft
  Windows.

* Wait for xapian-tcpsrv processes to finish before moving on to the next
  testcase under __WIN32__ like we already do on POSIX platforms.

matcher:

* Handle pruning under a positional check.  This used to be impossible, but
  since 1.4.13 it can happen as we now hoist AND_NOT to just below where we
  hoist the positional checks.  The code on master already handles pruning here
  so this bug is specific to the RELEASE/1.4 branch.  Fixes #796, reported by
  Oliver Runge.

* When searching with collapsing over multiple shards, at least some of which
  are remote, uncollapsed_upper_bound could be too low and
  uncollapsed_lower_bound too high.  This was causing assertion failures in
  testcases msize1 and msize2 under test harness backends
  multi_glass_remoteprog_glass and multi_remoteprog_glass.

* Internally we no longer calculate a bogus total_term_count as the sum of
  total_length * doc_count for all shards.  Instead we just use the sum of
  total_length, which gives the total number of term occurrences.  This change
  should improve the estimated collection_freq values for synonyms.

* Several places where we might divide zero by zero in a database where wdf was
  always zero have been fixed.

* Optimise OP_AND_NOT better.  We now combine its left argument with other
  connected and-like subqueries, and gather up and hoist the negated subqueries
  and apply them together above the combined and-like subqueries, just below
  any positional filters.

* Optimise OP_AND_MAYBE better.  We now combine its left argument with other
  connected and-like subqueries, and gather up and hoist the optional
  subqueries and apply them together above the combined and-like subqueries and
  any hoisted positional filters.

* Treat all BoolWeight queries as scaled by 0 - we can optimise better if we
  know the query is unweighted.

build system:

* configure: Stop using AC_FUNC_MEMCMP.  The autoconf manual marks it as
  "obsolescent", and it seems clear that nobody's relying on it as we're
  missing the "'AC_LIBOBJ' replacement for 'memcmp'" which it would try to
  use if needed.

glass backend:

* Allow zlib compression to reduce size by one byte.  We were specifying an
  output buffer size one byte smaller than the input, but it appears zlib won't
  use the final byte in the buffer, so we actually need to pass the input size
  as the output buffer size.

* Only try to compress Btree item values > 18 bytes, which saves CPU time
  without sacrificing any significant size savings.

remote backend:

* Fix match stats when searching with collapsing over multiple shards and at
  least some shards are remote.  Bug discovered by Tanmay Sachan's test harness
  improvements.

* Ignore orphaned remote protocol replies which can happen when searching with
  a remote shard if an exception is thrown by another shard.  Bug discovered
  by Tanmay Sachan's test harness improvements.

* Wait for xapian-progsrv child to exit when a remote Database or
  WritableDatabase object is closed under __WIN32__ like we already do for
  POSIX platforms.

documentation:

* HACKING: Replace release docs with pointer to the developer guide where they
  are now maintained.

* Correct documentation of initial messages in replication protocol.

tools:

* quest: Report bounds and estimate of number of matches.

* xapian-delve: Improve output when database revision information is not
  available.  We now specially handle the cases of a DB with multiple shards
  and a backend which doesn't support get_revision().

portability:

* Eliminate 2 uses of atoi().  These are potentially problematic in a
  multithreaded application if setlocale() is called by another thread at the
  same time.  See #665.

* Don't check __GNUC__ in visibility.h as the configure probe before defining
  XAPIAN_ENABLE_VISIBILITY checks that the visibility attributes work.  This
  probably makes no difference in practice, as all compilers we're aware of
  which support symbol visibility also define __GNUC__.

* Document Sun C++ requires --disable-shared.  Closes #631.

* Fix warning from GCC 9 with -Wdeprecated-copy (which is enabled by -Wextra)
  if a reference to an Error object is thrown.

* Suppress GCC warning in our API headers when compiling code using Xapian with
  GCC and -Wduplicated-branches.

* Mark some internal classes as final (following GCC -Wsuggest-final-types
  suggestions to allow some method calls to be devirtualised).

* Fix to build with --enable-maintainer-mode and Perl < 5.10, which doesn't
  have the `//=` operator.  It's unlikely developers will have such an old
  Perl, but the mingw environment on appveyor CI does.  The use of `//=` was
  introduced by changes in 1.4.10.

Log message:
Fix checksum on new patch.

Log message:
Apply previous fix to PHP5 as well.

Log message:
Reorder includes in PHP bindings to fix SmartOS bulk build error:
"/usr/include/locale.h:53:12: error: 'lconv' is already declared in this \ 
scope"
<https://trac.xapian.org/ticket/793>

Log message:
Update to 1.4.12. From the changelog:

API:

* Xapian::PostingSource: When a PostingSource without a clone() method is used
  with a Database containing multiple shards, the documented behaviour has
  always been that Xapian::InvalidOperationError is thrown.  However, since at
  least 1.4.0, this exception hasn't been thrown, but instead a single
  PostingSource object would get used for all the shards, typically leading to
  incorrect results.  The actual behaviour now matches what was documented.

* Xapian::Database: Add size() method which reports the number of shards.

* Xapian::Database::check(): You can now pass a stub database which will check
  all the databases listed in it (or throw Xapian::UnimplementError for
  backends which don't support checking).

* Xapian::Document: When updating a document use a emplace_hint() to make the
  bulk insertion O(n) instead of O(n·log(n)), and use std::move() to avoid
  copying OmDocumentTerm objects.

* Xapian::Query: Add missing get_unique_terms_end() method.

* Xapian::iterator_valid(): Implement for Utf8Iterator

testsuite:

* Fix keepalive1 failures on some platforms.  On some platforms a timeout
  gives NetworkTimeoutError and on others NetworkError - since 1.4.10 changed
  to checking the exact exception type, keepalive1 has been failing on the
  former set of platforms.  We now just check for NetworkError or a subclass
  here (since NetworkTimeoutError is a subclass of NetworkError).

* Run cursordelbug1 testcase with multi databases too.

matcher:

* Ownership of PostingSource objects during the match now makes use of the
  optional reference-counting mechanism rather than a separate flag.

remote backend:

* Fix remote protocol design bug.  Previously some messages didn't send a reply
  but could result in an exception being sent over the link.  That exception
  would then get read as a response to the next message instead of its actual
  response so we'd be out of step.  Fixes #783, reported by Germán M. Bravo.
  This fix necessitated a minor version bump in the remote protocol (to 39.1).
  If you are upgrading a live system which uses the remote backend, upgrade the
  servers before the clients.

* Fix socket leaks on errors during opening a database.  Fixes
  https://github.com/xapian/xapian/pull/237 and #781, reported by Germán M.
  Bravo.

* Don't close remote DB socket on receiving EOF as the levels above won't
  know it's been closed and may try to perform operations on it, which would be
  problematic if that fd gets reused in the meantime.  Leaving it open means
  any further operations will also get EOF.  Reported by Germán M. Bravo.

* We add a wrapper around the libc socket() function which deals with the
  corner case where SOCK_CLOEXEC is defined but socket() fails if it is
  specified (which can happen with a newer libc and older kernel).
  Unfortunately, this wrapper wasn't checking the returned value from socket()
  correctly, so when SOCK_CLOEXEC was specified and non-zero it would create
  the socket() with SOCK_CLOEXEC, then leak that one and create it again
  without SOCK_CLOEXEC.  We now check the return value properly.

* Fix potential infinite loop in ValueCountMatchSpy::merge_results() if passed
  serialised results with extra data appended (which shouldn't happen in normal
  use).

build system:

* Current versions of valgrind result in false positives on current versions of
  macOS, so on this platform configure now only enables use of valgrind if it's
  specified explicitly.  Fixes #713, reported by Germán M. Bravo.

* Refactor macros to probe for compiler flags so they automatically cache
  their results and consistently report success/failure.

* Rename our custom TYPE_SOCKLEN_T macro to XAPIAN_TYPE_SOCKLEN_T.  The
  AX_TYPE_SOCKLEN_T macro defines an alias of TYPE_SOCKLEN_T for itself which
  means it can get used instead in some situations, but it isn't compatible
  with our macro.  We can't just switch to AX_TYPE_SOCKLEN_T as it doesn't
  handle cases we need, so just rename our macro to avoid potential problems.

documentation:

* Improve API documentation for Xapian::Query class.  Add missing doc
  comments and improve some of the existing ones.  Problems highlighted by
  Дилян Палаузов in #790.

* Add Unicode consortium names and codes for categories from Chapter 4, Version
  11 of the Unicode standard.  Patch from David Bremner.

* Improve configure --help output - drop "[default=no]" for --enable-*
  options which default off.  Fixes #791, reported by and patch from Дилян
  Палаузов.

* Fix API documentation typo - Query::op (the type) not op_ (a parameter name).

* Note which version Document::remove_postings() was added in.

* In the remote protocol documentation, MSG_REPLACEDOCUMENTTERM was documented
  as not having a reply, but actually REPLY_ADDDOCUMENT is sent.

* Update list of <xapian/iterator.h> users.

tools:

* copydatabase: A change in 1.4.6 which added support for \ as directory
  separator on platforms where that's the norm broke the code in copydatabase
  which removes a trailing slash from input databases.  Bug reported and
  culprit commit identified by Eric Wong.

portability:

* Resolve crash on Windows when using clang-cl and MSVC.  Reported by Christian
  Mollekopf in https://github.com/xapian/xapian/pull/256.

* Add missing '#include <cstring>'.  Patch from Tanmay Sachan.

* Fix str() helper function when converting the most negative value
  of a signed integer type.

* Avoid calling close() on fd we know must actually be a WIN32 SOCKET.

* Include <ios> not <iomanip> for std::boolalpha.

* Rework setenv() compatibility handling.  Now that Solaris 9 is dead we can
  assume setenv() is provided by Unix-like platforms (POSIX requires it).  For
  other platforms, provide a compatibility implementation of setenv() which
  so the compatibility code is encapsulated in one place rather than replicated
  at every use.

* Fix maintainer-mode builds on Solaris where /bin/tr is not POSIX compliant.
  We now use the simple workaround suggested by the autoconf manual.

* Improve support for Sun C++ (see #631):

  + Suppress unhelpful warning for lambda with multiple return statements.

  + Enable reporting the tags corresponding to warnings, which we need
    to know in order to suppress any new unhelpful warnings.

  + Adjust our workaround for bug with this compiler's <cmath> header to avoid
    a compiler warning.

  + Use -xldscope=symbolic for Sun C++.  This flag is roughly equivalent to
    -Bsymbolic-functions which we've probed for with GNU ld since Xapian 1.0.0.

And from the changelog for the language bindings:

Documentation:

* Update bindings HACKING document.  Reported as out of date by Niwesh Gupta.

CSharp:

* Work around mono terminfo parsing bug - older cli-sn fails with e.g.
  TERM=xterm-256color due to: https://github.com/mono/mono/issues/6752
  Encountered on Kubuntu 18.10 and debugged by Tejasvi Tomar.  Seems to be
  fixed in the mono version in Debian buster.

Perl:

* Suppress warnings from older Perl headers due to use of constructs which look
  like C++11 user-defined literals.  They're fixed in newer versions so they're
  just noise in our build.  We were working around these in the CI build, so
  drop that workaround as we want to make the build warning-clean for users
  too.  Reported by daniel93 on #xapian.

Python3:

* Fix build for changes in Sphinx 2.0 (which drops support for sphinx.main()).
  Fixes #778, reported by karolyi.  Also reported by Gaurav Arora.

* We now throw UnicodeEncodeError for bad Unicode string input.  Previously
  cases such as a lone surrogate would be handled by quietly skipping the bad
  codepoints when converting to UTF-8 to pass to Xapian.

* We no longer use the deprecated old-style Py_UNICODE API, which currently
  gives deprecation warnings and is slated to be removed in Python 4.0.

Ruby:

* Add support for block iteration.  All the iterator methods in the Ruby API
  now accept an optional block.  If no block is given an array is returned so
  existing code will still work.  Partly based on a patch in
  https://github.com/xapian/xapian/pull/232 from Cong Ding.

* Add missing wrappers for all the C++ methods returning iterators which
  weren't wrapped for Ruby.  Fixes #777, reported by do.

* Suppress warnings from Ruby 2.3 headers due to use of register and
  constructs which look like C++11 user-defined literals.  They're fixed in
  newer versions so they're just noise in our build.  We were working around
  these in the CI build, so drop that workaround as we want to make the build
  warning-clean for users too.  Reported by daniel93 on #xapian.

* smoketest.rb: Don't leave temporary databases behind in /tmp.

Log message:
Add rpath to an output of xapian-config --libs, bump PKGREVISION