Question

This code sample is not able to be compiled. Any work arounds out there?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    using church = Func<dynamic, dynamic, dynamic>;

    class Program
    {
        static void Main(string[] args)
        {
            church True = (a, b) => a;
            church False = (a, b) => b;

            Func<church, church, church> And = (x, y) => x(y(True, False), False);
        }
    }
}

Error 6 Internal Compiler Error (0xc0000005 at address 5476A4CC): likely culprit is ‘EMITIL’. An internal error has occurred in the compiler. To work around this problem, try simplifying or changing the program near the locations listed below. Locations at the top of the list are closer to the point at which the internal error occurred. Errors such as this can be reported to Microsoft by using the /errorreport option. TestApplication

Answer 1

I reproduced the crash using VS2010 (WinXP 64).

Two workarounds:

1. don’t use the using alias

The following code compiles cleanly on VS2010:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Func<dynamic, dynamic, dynamic> True = (a, b) => a;
            Func<dynamic, dynamic, dynamic> False = (a, b) => b;

            Func<Func<dynamic, dynamic, dynamic>, 
                 Func<dynamic, dynamic, dynamic>,
                 Func<dynamic, dynamic, dynamic> > And 
                = (x, y) => x(y(True, False), False);
        }
    }
}

2. use the Mono compiler

No problem with Mono 2.10 compiler (dmcs).

[mono] /tmp @ dmcs test.cs
test.cs(18,42): warning CS0219: The variable `And' is assigned but its value is never used
Compilation succeeded - 1 warning(s)
[mono] /tmp @ ./test.exe 
[mono] /tmp @ 

This was tested on linux.

1. You can run binaries created with mono on Windows .NET.
2. Mono compiler comes with an installer MSI and runs on Windows as well.