[platform-testers] new snapshot available: grep-3.6.27-20b4

[Jim Meyering]

In addition to the NEWS-noted items, there have been improvements in
both regex and dfa gnulib modules, so I want to make a release in the
next week or so.

grep snapshot:
  https://meyering.net/grep/grep-ss.tar.xz      1.6 MB
  https://meyering.net/grep/grep-ss.tar.xz.sig
  https://meyering.net/grep/grep-3.6.27-20b4.tar.xz

Changes in grep since v3.6:

Helge Kreutzmann (1):
      doc: adjust man page syntax

Jim Meyering (13):
      maint: post-release administrivia
      tests: enable warnings for the gnulib-tests subdir
      build: update gnulib to latest for warning fixes
      grep: avoid performance regression with many patterns
      grep: use of --unix-byte-offsets (-u) now elicits a warning
      build: update gnulib to latest
      maint: add parentheses to avoid new clang-10 warning
      build: update gnulib to latest
      build: avoid long-string warnings in gnulib tests
      doc: man: fix -L description and improve -l's
      build: update gnulib to latest
      build: update gnulib to latest
      build: update gnulib to latest

Kevin Locke (2):
      doc: man: add --group-separator/--no-group-separator
      doc: usage: --group-separator/--no-group-separator

Marek Suppa (1):
      doc: fix missing right curly brace

Mateusz Okulus (1):
      doc: note that -H is a GNU extension in man page, too

Paul Eggert (9):
      doc: clarify special chars and }
      build: update gnulib submodule to latest
      maint: run "make update-copyright"
      doc: update grep.texi cite to 2021
      maint: copy bootstrap, tests/init.sh from Gnulib
      doc: further clarify regexp structure
      doc: improve examples and wording
      build: update gnulib submodule to latest
      build: update gnulib submodule to latest

====================================
NEWS
** Changes in behavior

  Use of the --unix-byte-offsets (-u) option now evokes a warning.
  Since 3.1, this Windows-only option has had no effect.

** Bug fixes

  Preprocessing N patterns would take at least O(N^2) time when too many
  patterns hashed to too few buckets. This now takes seconds, not days:
  : | grep -Ff <(seq 6400000 | tr 0-9 A-J)
  [Bug#44754 introduced in grep 3.5]


====================================
Changes in gnulib since v3.6:

* gnulib bd90572c03...1cb09be022 (855): (showing only regex- and dfa-related 
changes)
  > regex-quote: Improve GCC 11 allocation-deallocation checking.
  > dfa: Improve GCC 11 allocation-deallocation checking.
  > dfa: omit unneeded malloc+free
  > dfa: improve -fanalyzer malloc checking
  > regex: pacify GCC 11.2.1's -fanalyzer
  > regex: pacify GCC 11.2 -fanalyzer
  > regex: modernize to newer regex bugset
  > regex: fix shell quoting problem in configuration
  > regex: fix undefined behavior
  > dfa: prefer idx_t for indexes
  > regex-tests: test for regressions fixed by the previous commit
  > regex: fix match with possessive quantifier
  > regex-tests: remove incorrect comment
  > dfa, etc.: prefer xreallocarray to older name
  > xalloc: new function xpalloc, from dfa
  > regex: Allow locking optimization independently of 'unlocked-io'.
  > regex: fix comment location
  > regex-tests: add bug 11053 test
  > regex: debug check for set member duplicates
  > regex: fix longstanding backref match bug
  > regex: avoid duplicate in espilon closure
  > regex-tests: fix typo
  > regex: make it easier to merge into glibc
  > regex: minor refactoring
  > regex: avoid undefined behavior
  > regex: improve comments
  > fnmatch, regex, fts: FALLTHROUGH consistency
  > regex: stop using alloca
  > regexec: remove alloca usage in build_trtable
  > regex: remove alloca usage on regex set_regs
  > regex-tests: tweak to avoid a clang-10 warning
  > regex: remove glibc21.m4