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Re: [RFC PATCH v2] grep: allow for run time disabling of JIT in PCRE

From
Junio C Hamano <gitster@pobox.com>
Date
Jul 31, 2019, 16:18 UTC
Message-ID
<xmqqlfweqis3.fsf@gitster-ct.c.googlers.com>
In-Reply-To
<nycvar.QRO.7.76.6.1907311434080.21907@tvgsbejvaqbjf.bet>
Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
Show 9 quoted lines
> For the record, I read
> https://public-inbox.org/git/xmqqh8flkgs2.fsf@gitster-ct.c.googlers.com/
> as encouraging a slightly more powerful argument in favor. Junio seemed
> to hope that PCRE2's own `pcre2grep` would behave that way, and that
> would give us plenty reason to just imitate it.
>
> I don't know whether `pcre2grep` behaves that way, even if it does not,
> I think the benefits of the auto fallback to the end user are
> considerable.
Thanks for digging that up ;-)  I do agree with what was said there.

JIT is merely an optimization, and we should be able to work without it and should not even bother the users with warning messages when we have to choose non-JIT codepath. Those who care about debugging can use a "--debug" option or something to figure out if their build on a particular pattern is or is not using JIT.

I think I read somebody (Carlo?) made that argument in the thread earlier, and I agree with that sentiment.

Previous: Johannes SchindelinNext: Johannes Schindelin
Message 16 of 23 in “grep: allow for run time disabling of JIT in PCRE”
  1. grep: allow for run time disabling of JIT in PCRECarlo Marcelo Arenas Belón, Jul 28, 2019
  2. Carlo ArenasJul 29, 2019
  3. Junio C HamanoJul 29, 2019
  4. Carlo ArenasJul 29, 2019
  5. Ævar Arnfjörð BjarmasonJul 29, 2019
  6. Carlo ArenasJul 29, 2019
  7. Ævar Arnfjörð BjarmasonJul 29, 2019
  8. Carlo ArenasJul 30, 2019
  9. grep: allow for run time disabling of JIT in PCRECarlo Marcelo Arenas Belón, Jul 29, 2019
  10. Carlo ArenasJul 29, 2019
  11. René ScharfeJul 29, 2019
  12. Junio C HamanoJul 29, 2019
  13. Carlo ArenasJul 30, 2019
  14. René ScharfeJul 30, 2019
  15. Johannes SchindelinJul 31, 2019
  16. Junio C HamanoJul 31, 2019
  17. Johannes SchindelinJul 31, 2019
  18. Ævar Arnfjörð BjarmasonJul 31, 2019
  19. Carlo ArenasAug 4, 2019
  20. grep: treat PCRE2 jit compilation memory error as non fatalCarlo Marcelo Arenas Belón, Aug 4, 2019
  21. Carlo ArenasAug 4, 2019
  22. Junio C HamanoAug 5, 2019
  23. Johannes SchindelinJul 31, 2019

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