[boost] Re: [hash] Expected behaviour of hashing quiet NaN?

From: Markus Schöpflin (markus.schoepflin_at_[hidden])
Date: 2005-04-18 10:09:40

Victor A. Wagner Jr. wrote:

> At Monday 2005-04-18 03:52, you wrote:
> 
>> Currently "functional/hash - hash_float_test" fails on Tru64/CXX6.5 
>> (See http://tinyurl.com/8opfo)
>>
>> The reason of the failure is that QNaN and 0 give the same hash code 
>> on this platform. I was wondering what the expected hash of QNAN 
>> actually should be. Is it some platform dependent value?
> 
> Am I missing something here?  Since it is obvious that one canNOT 
> generate a unique hash for all possible inputs, why should there 
> necessarily be a difference between any 2?

You're probably right. Maybe the author of the test could perhaps clarify 
the motivation for this test, then.

Markus