http://screencast.com/t/va5sIPGsq5
This happens when enum has multiple elements with the same value. Here is how Accessibility enum is defined in roslyn:
C#/// <summary>
/// Enumeration for common accessibility combinations.
/// </summary>
public enum Accessibility
{
/// <summary>
/// No accessibility specified.
/// </summary>
NotApplicable = 0,
// DO NOT CHANGE ORDER OF THESE ENUM VALUES
Private = 1,
ProtectedAndInternal = 2,
ProtectedAndFriend = ProtectedAndInternal,
Protected = 3,
Internal = 4,
Friend = Internal,
ProtectedOrInternal = 5,
ProtectedOrFriend = ProtectedOrInternal,
Public = 6
}