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Code Analyzer for C#

There is a newer version: 10.2.0.105762

Why is this an issue?
The use of == to compare two objects is expected to do a reference comparison. That is, it is expected to return true if
and only if they are the same object instance. Overloading the operator to do anything else will inevitably lead to the introduction of bugs by
callers.
public static bool operator ==(MyType x, MyType y) // Noncompliant: confusing for the caller
{
    // custom implementation
}

On the other hand, overloading it to do exactly that is pointless; that’s what == does by default.
public static bool operator ==(MyType x, MyType y) // Noncompliant: redundant
{
    if (x == null)
    {
        return y == null;
    }

    return object.ReferenceEquals(x,y);
}

Exceptions

   Classes with overloaded operator + or operator - are ignored. 
   Classes that implement IComparable<T> or IEquatable<T> most probably behave as value-type objects and are
  ignored. 

Resources
Documentation

   Reference types 
   Equality operators