Never understood this line of thought. Not everything needs to be super secure. Not everything is going to be an attack vector. No one is going to deploy this onto a production server where this program specifically is going to be the attack vector.
Memory safety is cool and all, but a program that effectively sums a bunch of numbers together isn't going to cause issues. Worst case the program segfaults
But I suppose it's not a very likely bug to have in this kind of tool.