.NET 4.5 verificationexception in FluentValidation

gistfile1.cs

Due to implementation details in the current C# compiler, the code

public class AbstractValidator<T>
{
    Func<CascadeMode> cascadeMode = () => ValidatorOptions.CascadeMode;
}

will generate IL for the AbstractValidator<T> constructor that contains a branch that appears before the call to the base class constructor (the System.Object constructor in this case). In the workaround code

public class AbstractValidator<T>
{
    static Func<CascadeMode> s_cascadeMode = () => ValidatorOptions.CascadeMode;
    Func<CascadeMode> cascadeMode = s_cascadeMode;
}

the C# compiler no longer emits the problematic branch into the constructor IL (again due to implementation details in the C# compiler).