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Re: [PATCH 1/5] usage.c: add a non-fatal bug() function to go with BUG()

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
May 26, 2022, 18:29 UTC
Message-ID
<220526.868rqo5enf.gmgdl@evledraar.gmail.com>
In-Reply-To
<xmqqleuo1beq.fsf@gitster.g>
On Thu, May 26 2022, Junio C Hamano wrote:
Show 23 quoted lines
> Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:
>
>> I don't think we should do it like that and keep it a BUG() not to call
>> BUG_if_bug() when we hit exit(), because e.g. in the case of
>> parse-options.c once we have the a bad "struct options" we don't want to
>> continue, as we might segfault, or have other bad behavior etc. So we'd
>> like to BUG() out as soon as possible.
>
> Oh, there is no question about that.  When we detect that the
> program is in an inconsistent and unexpected state, we would want to
> bug out instead of continuing at some point, and that is why we would
> want to have BUG_if_bug(), or exit_if_called_bug(), as I called in
> the message you are reponding to.
>
> What I am getting at is that the code often or usually calls
> BUG_if_bug() is not a reason to require it to be called, especially
> if there are conditional calls to bug() near the end of the program.
> Imagine a program, after finishing to respond to the end-user
> request, before the end of the program, performing some self sanity
> checks with a series of "if (condition) bug()", and there is no more
> thing that needs to be done other than exiting after such check.  I
> would have added such a call to sanity_check_refcnt() at the end of
> "git blame", for example, if the facility existed.

But you wouldn't want to just stick BUG_if_bug() at the end of those sanity checks?

I suppose I can drop the paranoia of requiring it, but since all existing callers want to act that way, and I couldn't imagine a case where you didn't want that I made it act that way.

Previous: Junio C HamanoNext: Junio C Hamano
Message 7 of 49 in “usage API: add and use a bug() + BUG_if_bug()”
  1. 0/5 usage API: add and use a bug() + BUG_if_bug()Ævar Arnfjörð Bjarmason, May 21, 2022
  2. 1/5 usage.c: add a non-fatal bug() function to go with BUG()Ævar Arnfjörð Bjarmason, May 21, 2022
  3. Junio C HamanoMay 25, 2022
  4. Junio C HamanoMay 26, 2022
  5. Ævar Arnfjörð BjarmasonMay 26, 2022
  6. Junio C HamanoMay 26, 2022
  7. Ævar Arnfjörð BjarmasonMay 26, 2022
  8. Junio C HamanoMay 26, 2022
  9. Ævar Arnfjörð BjarmasonMay 31, 2022
  10. Josh SteadmonMay 27, 2022
  11. Junio C HamanoMay 27, 2022
  12. 2/5 parse-options.c: use new bug() API for optbug()Ævar Arnfjörð Bjarmason, May 21, 2022
  13. Josh SteadmonMay 27, 2022
  14. 3/5 parse-options.c: use optbug() instead of BUG() "opts" checkÆvar Arnfjörð Bjarmason, May 21, 2022
  15. Junio C HamanoMay 25, 2022
  16. 4/5 receive-pack: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, May 21, 2022
  17. Junio C HamanoMay 25, 2022
  18. Josh SteadmonMay 27, 2022
  19. Andrei RybakMay 27, 2022
  20. 5/5 cache-tree.c: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, May 21, 2022
  21. Glen ChooMay 27, 2022
  22. Josh SteadmonMay 27, 2022
  23. 0/6 usage API: add and use a bug() + BUG_if_bug()Ævar Arnfjörð Bjarmason, May 31, 2022
  24. 1/6 common-main.o: move non-trace2 exit() behavior out of trace2.cÆvar Arnfjörð Bjarmason, May 31, 2022
  25. Junio C HamanoJun 1, 2022
  26. 2/6 usage.c: add a non-fatal bug() function to go with BUG()Ævar Arnfjörð Bjarmason, May 31, 2022
  27. Glen ChooMay 31, 2022
  28. Junio C HamanoJun 1, 2022
  29. 3/6 parse-options.c: use new bug() API for optbug()Ævar Arnfjörð Bjarmason, May 31, 2022
  30. 4/6 parse-options.c: use optbug() instead of BUG() "opts" checkÆvar Arnfjörð Bjarmason, May 31, 2022
  31. Josh SteadmonMay 31, 2022
  32. Junio C HamanoJun 1, 2022
  33. 5/6 receive-pack: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, May 31, 2022
  34. 6/6 cache-tree.c: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, May 31, 2022
  35. Junio C HamanoJun 1, 2022
  36. Josh SteadmonMay 31, 2022
  37. 0/6 usage API: add and use a bug() + BUG_if_bug()Ævar Arnfjörð Bjarmason, Jun 2, 2022
  38. 1/6 common-main.o: move non-trace2 exit() behavior out of trace2.cÆvar Arnfjörð Bjarmason, Jun 2, 2022
  39. Junio C HamanoJun 3, 2022
  40. Josh SteadmonJun 7, 2022
  41. Ævar Arnfjörð BjarmasonJun 7, 2022
  42. Josh SteadmonJun 7, 2022
  43. 3/6 parse-options.c: use new bug() API for optbug()Ævar Arnfjörð Bjarmason, Jun 2, 2022
  44. 2/6 usage.c: add a non-fatal bug() function to go with BUG()Ævar Arnfjörð Bjarmason, Jun 2, 2022
  45. 5/6 receive-pack: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, Jun 2, 2022
  46. 4/6 parse-options.c: use optbug() instead of BUG() "opts" checkÆvar Arnfjörð Bjarmason, Jun 2, 2022
  47. 6/6 cache-tree.c: use bug() and BUG_if_bug()Ævar Arnfjörð Bjarmason, Jun 2, 2022
  48. Junio C HamanoJun 2, 2022
  49. Glen ChooJun 2, 2022

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