vs2012/.net 4.5 RC Compiler error, when using ActionBlock, missing reference to System.Threading.Tasks

Question

Hello guys,

I'm using the TDF rc with .net 4.5, but when i declare an ActionBlock the compiler gives this error:

Error 1 The type 'System.Threading.Tasks.Task' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Threading.Tasks, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. 

However there is no such dll when i go to add a reference, and msdn tells me Task is in mscorelib.
i found this on SO:

http://stackoverflow.com/questions/10869730/problems-with-references-to-tpl-dataflow-and-tpl-in-vs-2012-rc

But surely that is not the way to go, atelast not at rtm, is this a bug in TDF or somewhere else? or am i doing something wrong?

regards/allan

Answer 1

To replicate, make a new console app, add the nuget package, then paste this and compile:

using System.Threading.Tasks.Dataflow;

namespace Sandbox
{
    class Program
    {
        static void Main(string[] args)
        {
            var a = new ActionBlock<int>(i => { });
        }
    }
}

Answer 2

As I said in the SO question, I have also posted this to Connect.

Answer 3

allan,

What build of the VS are you using? In Pre-RC bits this is to be expected.  The workaround is manually adding those assemblies to the console app.Let me know in case this is not your situation.

thanks

-alok

Answer 4

allan, svick,

  Another quick follow up.  If in fact you are using RC bits and hit this issues, please go to your project and remove the reference to System.Runtime, it should compile.  This should get you unblocked immediately.  We have identified the bug causing this and will fix it in the next release.

Hope that helps

cheers

-alok

Answer 5

Removing the reference does work, thanks.

Answer 6

yes, i'm using the RC (both vs and tdf) and removing said reference does resolve the issue for me as well, thanks guys :)

regards /allan

Answer 7

A quick update on this issue.  We have shipped an updated NuGet package for Dataflow which fixes the above issues. New installations of NuGet for this library will not suffer from this issue.

Please let us know of any other issues and let us know of any more feedback

cheers

-alok

Answer 8

This is still not fixed.

In VS2012, I try to use the library, and get the following error:

 "Reference required to assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' containing the base class 'System.Object'. Add one to your project."

It won't compile unless I add the reference. Whereupon VS crashes. Wtf?

Answer 9

Same here!