Changes 2.16:

** Bug fixes

  Fix gnulib-provided maint.mk so that the release procedure described
  in README-release actually does what we want.  Before that fix, that
  procedure resulted in a grep-2.15 tarball that would lead to a grep
  binary whose --version-reported version number was 2.14.51...

  The fix to make \s and \S work with multi-byte white space broke
  the use of each shortcut whenever followed by a repetition operator.
  For example, \s*, \s+, \s? and \s{3} would all malfunction in a
  multi-byte locale.  [bug introduced in grep-2.15]

  The fix to make grep -P work better with UTF-8 made it possible for
  grep to evoke a larger set of PCRE errors, some of which could trigger
  an abort.  E.g., this would abort:
    printf '\x82'|LC_ALL=en_US.UTF-8 grep -P y
  Now grep handles arbitrary PCRE errors.  [bug introduced in grep-2.15]

  Handle very long lines (2GiB and longer) on systems with a deficient
  read system call.


(adam)