These [DisallowNull] attributes should be removed:

• IEqualityComparer<T>.GetHashCode(T)
• EqualityComparer<T>.GetHashCode(T)

The following scenarios are impacted:

• For netcoreapp3.0 and newer targets, the reference assemblies should be rewritten to remove the existing attribute from the reference assembly
• For earlier targets, the attributes should simply not be added during the rewrite process