The issue is not reproducible with 32bit Editor.
Steps to reproduce:
1. Download and open attached project. It contains a usual MonoBehaviour class with:
public int a;
void Start()
{
Foobar(10/a);
}
public void Foobar(int amount) {}
Attached to a game object

2. Enter play mode. Editor crashes. This is reproducible with a function defined in the same class. Issue using Mathf.Abs() was not reproduced, editor would throw division by zero exception.