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Subject: Re: [boost] [uuid] basic_random_generator doesn't produce a fully randomized uuid when sizeof(unsigned long) == 4
From: Scott McMurray (me22.ca+boost_at_[hidden])
Date: 2010-03-02 10:53:10


On 2 March 2010 06:21, Sylvester-Bradley, Gareth
<Gareth.Sylvester-Bradley_at_[hidden]> wrote:
>
> Is 8 bytes of randomness enough, or is this a mistake?
>

This is definitely a mistake, since it means only about 4 billion 'til
a collision, completely destroying the utility of random UUIDs. Not
to mention that shifting by >= the width isn't well-defined, which
means there's no guarantee it even gives different UUIDs.

Good catch.


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