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Re: Is #pragma pack violates ODR for classes?

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On 8/30/2011 9:41 PM, Fedor Rodikov wrote:
> This #include directive enclosed by #paragma pack in each cpp and the
> value of this packing not the same. Does the X violate ODR or not?
> Could a different packing in different translation units leads to UB?

Well, '#pragma pack' is not really a part of the language specification 
(at least yet), so there's no formal answer to your question. But if you 
understand the rationale behind various ODR requirements, you have to 
conclude that using different packing for the same class in different 
translation units does indeed violate the intended restrictions of ODR. 
So, with above remarks, the behavior is de-facto undefined.

-- 
Best regards,
Andrey Tarasevich

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Thread

Is #pragma pack violates ODR for classes? Fedor Rodikov <rodikov.fedor@gmail.com> - 2011-08-30 21:41 -0700
  Re: Is #pragma pack violates ODR for classes? Ian Collins <ian-news@hotmail.com> - 2011-08-31 16:58 +1200
    Re: Is #pragma pack violates ODR for classes? Fedor Rodikov <rodikov.fedor@gmail.com> - 2011-08-31 00:05 -0700
    Re: Is #pragma pack violates ODR for classes? James Kanze <james.kanze@gmail.com> - 2011-09-01 16:00 -0700
  Re: Is #pragma pack violates ODR for classes? Goran <goran.pusic@gmail.com> - 2011-08-31 00:23 -0700
  Re: Is #pragma pack violates ODR for classes? Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-31 09:33 -0700
    Re: Is #pragma pack violates ODR for classes? Fedor Rodikov <rodikov.fedor@gmail.com> - 2011-09-01 02:52 -0700

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