Issue after updating to mono 4.0.1 on Ubuntu

Question

I just upgraded to the just released Mono version 4.0.1 on my ubuntu machines. The previous installed version of mono was 3.2.7 (if I remember correctly).

Now the issue:

My first issue is regarding SignalR and self-hosting. I have a .NET 4.5.1 console application in which I self host NancyFx, Web Api and SignalR using OWIN. When running on mono 3.2.7 there was no issues to my knowledge but when I try to start the application on mono 4.0.1 I get the following stack trace:

Unhandled Exception:
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.InvalidProgramException: Invalid IL code in (wrapper delegate-invoke) <Module>:invoke_callvirt_CancellationTokenRegistration_CancellationToken&_Action`1<object>_object (System.Threading.CancellationToken&,System.Action`1<object>,object): IL_0057: castclass 0x00000007

  at Microsoft.AspNet.SignalR.Infrastructure.CancellationTokenExtensions.SafeRegister (CancellationToken cancellationToken, System.Action`1 callback, System.Object state) [0x00000] in <filename unknown>:0 
  at Microsoft.AspNet.SignalR.Hosting.HostDependencyResolverExtensions.InitializeResolverDispose (IDependencyResolver resolver, CancellationToken hostShutdownToken) [0x00000] in <filename unknown>:0 
  at Microsoft.AspNet.SignalR.Hosting.HostDependencyResolverExtensions.InitializeHost (IDependencyResolver resolver, System.String instanceName, CancellationToken hostShutdownToken) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions.UseSignalRMiddleware[HubDispatcherMiddleware] (IAppBuilder builder, System.Object[] args) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions.RunSignalR (IAppBuilder builder, Microsoft.AspNet.SignalR.HubConfiguration configuration) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions+<>c__DisplayClass1.<MapSignalR>b__0 (IAppBuilder subApp) [0x00000] in <filename unknown>:0 
  at Owin.MapExtensions.Map (IAppBuilder app, PathString pathMatch, System.Action`1 configuration) [0x00000] in <filename unknown>:0 
  at Owin.MapExtensions.Map (IAppBuilder app, System.String pathMatch, System.Action`1 configuration) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions.MapSignalR (IAppBuilder builder, System.String path, Microsoft.AspNet.SignalR.HubConfiguration configuration) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions.MapSignalR (IAppBuilder builder, Microsoft.AspNet.SignalR.HubConfiguration configuration) [0x00000] in <filename unknown>:0 
  at Owin.OwinExtensions.MapSignalR (IAppBuilder builder) [0x00000] in <filename unknown>:0 

I have no clue to what this error could mean and I'm greatful for all assistance. I'm using Microsoft ASP.NET SignalR Self Host package version 2.2.0.

And as a side note, I've compiled all my assemblies on the new mono version.

Kind regards, Simon

Answer 1

This turned out to be a Mono issue which was recently fixed: https://bugzilla.xamarin.com/show_bug.cgi?id=29665