NitImplementedException when compiling with /clr:pure

NotImplementedException: The requested feature is not implemented.
System.Runtime.InteropServices.Marshal.GetExceptionPointers () (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Runtime.InteropServices/Marshal.cs:388)
<Module>.___CxxCallUnwindDtor (System.MonoFNPtrFakeClass pDtor, System.Void* pThis)
<Module>..cctor ()
Rethrow as TypeInitializationException: An exception was thrown by the type initializer for <Module>
System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:513)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:519)
System.Reflection.MonoCMethod.Invoke (BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:528)
System.Reflection.ConstructorInfo.Invoke (System.Object[] parameters) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/ConstructorInfo.cs:77)
System.Activator.CreateInstance (System.Type type, Boolean nonPublic) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System/Activator.cs:372)
System.Activator.CreateInstance (System.Type type) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System/Activator.cs:254)
TestScript.Awake () (at Assets/Scripts/TestScript.cs:12)