C# - Inconsistent math operation result on 32-bit and 64-bit

Question

Consider the following code:

double v1 = double.MaxValue;
double r = Math.Sqrt(v1 * v1);

r = double.MaxValue on 32-bit machine r = Infinity

Answer 1

The problem is that Math.Sqrt expects a double as argument. v1 * v1 cannot be stored as double and overflows resulting in undefined behavior.