Get 32-bit hash value from boost::hash

Question

I am using boost::hash to get hash value for a string. But it is giving different hash values for same string on Windows 32-bit and Debian 64-bit systems.

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Answer 1

Use some of the well-known universal hash functions such as SHA instead, because those are supposed to guarantee that the same string will have the same hash everywhere. Note that in case you are doing something security-related, SHA might be too fast. It's a strange thing to say, but sometimes fast does not mean good as it opens a possibility for a brute force attack - in this case, there are other, slower hash function, some of which basically re-apply SHA many times in a row. Another thing, if you are hashing passwords, remember to salt them (I won't go into details, but the information is readily accessible online).