Kokkos RNG normal() function hangs for small seed value

[stanmoore1]

The Kokkos RNG normal() function hangs in its while loop if the RNG seed is a small integer (i.e. 0). It seems like the RNG warmup isn't working properly, or is this expected?

[crtrott]

It probably doesn't hang, but it doesn't converge. So we need to something better for warmup. Btw, is it just zero?

[stanmoore1]

Yeah, what happened is that our collaborator used the MPI rank as the seed, and for a single core, the seed becomes 0.

[stanmoore1]

So even a check on if the seed is valid (i.e. >0) could be helpful.

[mhoemmen]

@crtrott would it make sense just to "time out" of the loop if it does too many iterations (whatever we think "too many" should mean)?

[crtrott]

I'll fix it.

[stanmoore1]

Thanks!