computing hash values, integral types versus struct/class

Posted by aaa on Stack Overflow See other posts from Stack Overflow or by aaa
Published on 2010-03-13T19:12:43Z Indexed on 2010/03/13 19:15 UTC
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hash

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primitive-types

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pod-types

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c++

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efficiency

hello

I would like to know if there is a difference in speed between computing hash value (for example std::map key) of primitive integral type, such as int64_t and pod type, for example struct { int16_t v[4]; };.

I know this is going to implementation specific, so my question ultimately pertains to gnu standard library. Thanks

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