Log Message:
Update to 1.2.19. From the changelog:

API:

* Xapian::BM5Weight:

  + Improve BM25 upper bound in the case when our wdf upper bound > our
    document length lower bound.  Thanks to Craig Macdonald for pointing out
    this trick.

  + Pre-multiply termweight by (param_k1 + 1) rather than doing it for
    every weighted term in every document considered.

testsuite:

* Don't report apparent leaks of fds opened on /dev/urandom - at least on
  Linux, something in the C library seems to lazily open it, and the report of
  a possible leak followed by assurance that it's OK really is just noise we
  can do without.

matcher:

* Fix false matches reported for non-exact phrases in some cases.  Fixes the
  reduced testcase in #657, reported by Jean-Francois Dockes.

brass backend:

* Only full sync after writing the final base file (only affects Max OS X).

chert backend:

* Only full sync after writing the final base file (only affects Max OS X).

flint backend:

* Only full sync after writing the final base file (only affects Max OS X).

build system:

* For Sun's C++ compiler, pass -library=Crun separately since libtool looks for
  " -library=stlport4 " (with the spaces).  (fixes#650)

* Remove .replicatmp (created by the test suite) upon "make clean".

documentation:

* include/xapian/compactor.h: Fix formatting of doxygen comment.

* HACKING: freecode no longer accepts updates, so drop that item from the
  release checklist.

* docs/overview.rst: Add missing database path to example of using
  xapian-progsrv in a stub database file.

portability:

* Suppress unused typedef warnings from debugging logging macros, which occur
  in functions which always exit via throwing an exception when compiling with
  recent versions of GCC or clang.

* Fix debug logging code to compile with clang.  (fixes #657, reported by
  Germán M. Bravo)

debug code:

* Add missing RETURN() markup for debug logging in a few places, highlighted by
  warnings from recent GCC.

* Fix incorrect return types in debug logging annotations so that code compiles
  when configured with --enable-log.