HashSet.IntersectWIth使用自定义的IEqualityComparer在Mono中产生错误的结果

我遇到的问题是，某段代码在。net 4.0中按预期运行，但在Mono 2.6(在Unity3D中)中没有。请看:

    void Test()
    {
        Func<string, MemberInfo> get = name => typeof(HSTest).GetField(name, BindingFlags.Public | BindingFlags.Instance);
        var m1 = new TestMember { MemberInfo = get("x") };
        var m2 = new TestMember { MemberInfo = get("y") };
        var m3 = new TestMember { MemberInfo = get("x") };
        var m4 = new TestMember { MemberInfo = get("x") };
        var m5 = new TestMember { MemberInfo = get("a") };
        var m6 = new TestMember { MemberInfo = get("b") };
        var l1 = new List<TestMember> { m1, m2, m3 };
        var l2 = new List<TestMember> { m4, m5, m6 };
        var ll = new List<List<TestMember>> { l1, l2 };
        var comparer = new TestMemberComparer();
        var res = IntersectAll(ll, comparer);
        res.Foreach(Debug.Log); // In .NET this prints "x" in Mono it doesn't print anything
    }
    // Credits to Jon Skeet
    public static List<T> IntersectAll<T>(List<List<T>> lists, IEqualityComparer<T> comparer)
    {
        HashSet<T> hashSet = null;
        foreach (var list in lists)
        {
            if (hashSet == null)
            {
                hashSet = new HashSet<T>(list, comparer);
            }
            else
            {
                hashSet.IntersectWith(list);
            }
        }
        return hashSet == null ? new List<T>() : hashSet.ToList();
    }
}
public class TestMember
{
    public MemberInfo MemberInfo { get; set; }
}
public class TestMemberComparer : IEqualityComparer<TestMember>
{
    public bool Equals(TestMember x, TestMember y)
    {
        return x.MemberInfo.Equals(y.MemberInfo);
    }
    public int GetHashCode(TestMember obj)
    {
        return obj.MemberInfo.GetHashCode();
    }
}
public class HSTest
{
    public int x;
    public int y;
    public int z;
    public int a;
    public int b;
    public int c;
}

在。net中，我得到'x'作为交集的结果，在Mono中，我没有得到任何回报。

任何想法?

编辑:

使用名称而不是实际的MemberInfo对象也没有帮助

public class TestMemberComparer : IEqualityComparer<TestMember>
{
    public bool Equals(TestMember x, TestMember y)
    {
        return x.MemberInfo.Name.Equals(y.MemberInfo.Name);
    }
    public int GetHashCode(TestMember obj)
    {
        return obj.MemberInfo.Name.GetHashCode();
    }
}

我还应该提到，使用不同的方式相交不会引起任何问题(无论是在GetHashCode和Equals中使用MemberInfo和MemberInfo.Name时):

var res = ll.Aggregate((p, n) => p.Intersect(n, comparer).ToList());

编辑:下面是比较器

内的一些日志的测试

    void Test()
    {
        // ... define everything like in previous code
        var comparer = new TestMemberComparer();
        var hs = new HashSet<TestMember>(l1, comparer);
        hs.IntersectWith(l2);
        hs.ToList().Foreach(Debug.Log);
    }
public class TestMemberComparer : IEqualityComparer<TestMember>
{
    public bool Equals(TestMember left, TestMember right)
    {
        bool result = left.MemberInfo.Name.Equals(right.MemberInfo.Name);
        Debug.Log("Comparing `" + left.MemberInfo.Name + "` with `" + right.MemberInfo.Name + "` Result: " + result);
        return result;
    }
    public int GetHashCode(TestMember obj)
    {
        int hc = obj.MemberInfo.Name.GetHashCode();
        Debug.Log("Hash code: " + hc);
        return hc;
    }
}

执行时得到的结果是:

Hash code: 120
Hash code: 120
Hash code: 121
Comparing `x` with `x` Result: True
Hash code: 120
Hash code: 120
Hash code: 120
Comparing `x` with `x` Result: True
Hash code: 121
Comparing `y` with `y` Result: True
Hash code: 97
Hash code: 97
Hash code: 98
Hash code: 98

var m1 = get("x");
var m2 = get("x");
Console.WriteLine(m1.Equals(m2));