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Re: Unaligned accesses in sha1dc

From
Andreas Schwab <schwab@suse.de>
Date
Jun 1, 2017, 10:08 UTC
Message-ID
<mvmmv9st3yv.fsf@suse.de>
In-Reply-To
<xmqqwp8w3uff.fsf@gitster.mtv.corp.google.com>
On Jun 01 2017, Junio C Hamano <gitster@pobox.com> wrote:
> Depending on the model of "ARM" (or "SPARC") emulated with QEMU, and
> depending on the OS that runs on such an "ARM" or "SPARC", we may
> not see this---if the emulated OS has the "software unaligned-access
> emulation" our userland may not see a SIGBUS.

Even if the architecture implements unaligned accesses in hardware, it is still undefined behaviour, and the compiler will (eventually) take advantage of it.

Andreas.
-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."
Previous: Junio C HamanoNext: Martin Ågren
Message 9 of 28 in “Unaligned accesses in sha1dc”
  1. Andreas SchwabJun 1, 2017
  2. Junio C HamanoJun 1, 2017
  3. Andreas SchwabJun 1, 2017
  4. Junio C HamanoJun 1, 2017
  5. brian m. carlsonJun 1, 2017
  6. Andreas SchwabJun 1, 2017
  7. Lars SchneiderJun 1, 2017
  8. Junio C HamanoJun 1, 2017
  9. Andreas SchwabJun 1, 2017
  10. Martin ÅgrenJun 1, 2017
  11. Ævar Arnfjörð BjarmasonJun 1, 2017
  12. Martin ÅgrenJun 1, 2017
  13. Martin ÅgrenJun 1, 2017
  14. Junio C HamanoJun 2, 2017
  15. Ævar Arnfjörð BjarmasonJun 2, 2017
  16. Martin ÅgrenJun 2, 2017
  17. Ævar Arnfjörð BjarmasonJun 2, 2017
  18. Martin ÅgrenJun 2, 2017
  19. Ævar Arnfjörð BjarmasonJun 2, 2017
  20. demerphqJun 2, 2017
  21. demerphqJun 2, 2017
  22. Ævar Arnfjörð BjarmasonJun 2, 2017
  23. Linus TorvaldsJun 2, 2017
  24. Junio C HamanoJun 3, 2017
  25. Liam R. HowlettJun 2, 2017
  26. Ævar Arnfjörð BjarmasonJun 2, 2017
  27. Junio C HamanoJun 3, 2017
  28. Andreas SchwabJun 1, 2017

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