zMult of large sparse matrices producing negative values for indices?

[amalagaura]

I am doing dot products of large sparse matrixes. I pass in C to zmult as a new sparse matrix. Works fine at 30k x 30k. At approx 100k x 100k (well under max int), it runs for 80min. After it finishes I run forEachNonZero and it gives negative row and column indices.

My guess is that it is having issues at values greater than square root of max int. There is some int overflow. An int which should be a long?