Log Message:
grep: update to 3.7.

** 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]

* Noteworthy changes in release 3.6 (2020-11-08) [stable]

** Changes in behavior

  The GREP_OPTIONS environment variable no longer affects grep's behavior.
  The variable was declared obsolescent in grep 2.21 (2014), and since
  then any use had caused grep to issue a diagnostic.

** Bug fixes

  grep's DFA matcher performed an invalid regex transformation
  that would convert an ERE like a+a+a+ to a+a+, which would make
  grep a+a+a+ mistakenly match "aa".
  [Bug#44351 introduced in grep 3.2]

  grep -P now reports the troublesome input filename upon PCRE execution
  failure.  Before, searching many files for something rare might fail with
  just "exceeded PCRE's backtracking limit".  Now, it also reports \ 
which file
  triggered the failure.