Can anyone explain to me why the following code throws System.Reflection.AmbiguousMatchException?

Question

using System;
using System.Reflection;

namespace A
{
  interface IObjectWithId<TId>
  {
    TId Id { get; }
  }
  interface IEntityBase : IObjectWithId<object>
  {
    new object Id { get; }
  }
  abstract class BusinessObject<TId> : IObjectWithId<TId>
  {
    public abstract TId Id { get; }
  }
  class EntityBase : BusinessObject<object>, IEntityBase
  {
    public override object Id { get { return null; } }
  }

  public static class Program
  {
    public static void Main()
    {
      Console.WriteLine(typeof(EntityBase).GetProperty("Id", BindingFlags.Instance | BindingFlags.Public));
    }
  }
}

I am getting this:

System.Reflection.AmbiguousMatchException was unhandled
  Message="Ambiguous match found."
  Source="mscorlib"
  StackTrace:
       at System.RuntimeType.GetPropertyImpl(String name, BindingFlags bindingAttr, Binder binder, Type returnType, Type[] types, ParameterModifier[] modifiers)
       at System.Type.GetProperty(String name, BindingFlags bindingAttr)
       at A.Program.Main() in C:\Home\work\A\Program.cs:line 26
  InnerException: 

Visual Studio about: Microsoft Visual Studio 2008 Version 9.0.30729.1 SP Microsoft .NET Framework Version 3.5 SP1

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EDIT:

Strangely enough, looks like other folks fail to reproduce it. Though it does crash on my machine every time. I found out that this code:

Console.WriteLine(typeof(EntityBase).GetProperty("Id", BindingFlags.Instance | BindingFlags.Public, null, typeof(object), Type.EmptyTypes, null));

Does work OK, although it should be the same.

Answer 1

Was this ever resolved? I currently have a very similar issue...

abstract class A
{
    public virtual Int64 Id { get; set; }
}

class B : A
{
    public override Int64 Id { get{...} set {...} }
}

Calling typeof(B).GetProperty("Id") works fine on my machine (returns the PropertyInfo of the overriden Id property in class B, however, a colleague of mine runs the same code on his machine and he get the AmbiguousMatchException thrown.

Any ideas?