This is v3 of a patch I originally sent in mid-2019:
https://lore.kernel.org/git/20190726150818.6373-9-avarab@gmail.com/ (local)

Back then we were near a release and the PCREv2 feature I'm using in
4/4 wasn't in any released version. Now it's in widely used releases,
so we can use it and fix some long-standing TODOs in invalid UTF-8
grep matching edge cases.

Ævar Arnfjörð Bjarmason (4):
  grep/pcre2 tests: don't rely on invalid UTF-8 data test
  grep/pcre2: simplify boolean spaghetti
  grep/pcre2: further simplify boolean spaghetti
  grep/pcre2: better support invalid UTF-8 haystacks

 Makefile                        |  1 +
 grep.c                          | 11 +++++--
 grep.h                          |  4 +++
 t/helper/test-pcre2-config.c    | 12 ++++++++
 t/helper/test-tool.c            |  1 +
 t/helper/test-tool.h            |  1 +
 t/t7812-grep-icase-non-ascii.sh | 53 ++++++++++++++++++++++++++++-----
 7 files changed, 74 insertions(+), 9 deletions(-)
 create mode 100644 t/helper/test-pcre2-config.c

-- 
2.29.2.222.g5d2a92d10f8