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Re: [PATCH v1] Travis: also test on 32-bit Linux

From
René Scharfe <l.s.r@web.de>
Date
Mar 10, 2017, 16:20 UTC
Message-ID
<04f4849c-e1e0-f0ac-5b1e-10a343391db4@web.de>
In-Reply-To
<20170310081759.yka476hnw4w3mghs@sigill.intra.peff.net>
Am 10.03.2017 um 09:18 schrieb Jeff King:
Show 26 quoted lines
> On Fri, Mar 10, 2017 at 01:14:16AM +0100, René Scharfe wrote:
>
>>>   2. Ones which just copy a single object, like:
>>>
>>>        memcpy(&dst, &src, sizeof(dst));
>>>
>>>      Perhaps we should be using struct assignment like:
>>>
>>>        dst = src;
>>>
>>>      here. It's safer and it should give the compiler more room to
>>>      optimize. The only downside is that if you have pointers, it is
>>>      easy to write "dst = src" when you meant "*dst = *src".
>>
>> Compilers can usually inline memcpy(3) calls, but assignments are
>> shorter and more pleasing to the eye, and we get a type check for
>> free.  How about this?
>
> Yeah, I mostly wasn't sure how people felt about "shorter and more
> pleasing". It _is_ shorter and there's less to get wrong. But the
> memcpy() screams "hey, I am making a copy" and is idiomatic to at least
> a certain generation of C programmers.
>
> I guess something like COPY(dst, src) removes the part that you can get
> wrong, while still screaming copy. It's not idiomatic either, but at
> least it stands out. I dunno.
Yes ...
> I think this misses the other two cases: (*dst, src) and (*dst, *src).

... and that's why I left them out. You can't get dst vs. *dst wrong with structs (at least not without the compiler complaining); only safe transformations are included in this round.

René
Previous: Jeff KingNext: Jeff King
Message 26 of 36 in “Travis: also test on 32-bit Linux”
  1. Travis: also test on 32-bit LinuxJohannes Schindelin, Feb 28, 2017
  2. Johannes SchindelinFeb 28, 2017
  3. Junio C HamanoMar 2, 2017
  4. Travis: also test on 32-bit LinuxLars Schneider, Mar 2, 2017
  5. Johannes SchindelinMar 2, 2017
  6. Lars SchneiderMar 2, 2017
  7. Johannes SchindelinMar 2, 2017
  8. Christian CouderMar 2, 2017
  9. Junio C HamanoMar 2, 2017
  10. Johannes SchindelinMar 3, 2017
  11. Junio C HamanoMar 3, 2017
  12. Junio C HamanoMar 4, 2017
  13. Junio C HamanoMar 4, 2017
  14. Lars SchneiderMar 4, 2017
  15. Vegard NossumMar 4, 2017
  16. Vegard NossumMar 4, 2017
  17. Vegard NossumMar 4, 2017
  18. Jeff KingMar 5, 2017
  19. line-log: use COPY_ARRAY to fix mis-sized memcpyJeff King, Mar 5, 2017
  20. Vegard NossumMar 5, 2017
  21. Jeff KingMar 5, 2017
  22. René ScharfeMar 10, 2017
  23. Jeff KingMar 10, 2017
  24. René ScharfeMar 10, 2017
  25. Jeff KingMar 10, 2017
  26. René ScharfeMar 10, 2017
  27. Jeff KingMar 10, 2017
  28. René ScharfeMar 10, 2017
  29. Junio C HamanoMar 10, 2017
  30. Jeff KingMar 10, 2017
  31. René ScharfeMar 10, 2017
  32. Junio C HamanoMar 10, 2017
  33. René ScharfeMar 11, 2017
  34. Ramsay JonesMar 2, 2017
  35. Lars SchneiderMar 5, 2017
  36. Ramsay JonesMar 5, 2017

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