@lindahua It is difficult to make a general criterion that works for all types and realisations. The problem is that 32 bit machine are rare so it is difficult to know when the tests fail on a 32 bit machine. How much longer will 32 bit machines be around?

Actually I think the magic seed here could be considered a feature. It revealed that the generated random numbers were different on 32 and 64 bit machines which they shouldn't unless documented.