UNetWeaver error in b9

I just updated my project from b5 to b9 and now I'm getting the following error:

Code (CSharp):

1. UNetWeaver error: Exception :System.IO.IOException: Sharing violation on path Temp\Assembly-CSharp.pdb
2.   at System.IO.File.Delete (System.String path) [0x00073] in <f826c2584fc94ec19a48a6576640bdc5>:0
3.   at Unity.UNetWeaver.Weaver.Weave (System.String assName, System.Collections.Generic.IEnumerable`1[T] dependencies, Mono.Cecil.IAssemblyResolver assemblyResolver, System.String unityEngineDLLPath, System.String unityUNetDLLPath, System.String outputDir) [0x002cf] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1862
4.   at Unity.UNetWeaver.Weaver.WeaveAssemblies (System.Collections.Generic.IEnumerable`1[T] assemblies, System.Collections.Generic.IEnumerable`1[T] dependencies, Mono.Cecil.IAssemblyResolver assemblyResolver, System.String outputDir, System.String unityEngineDLLPath, System.String unityUNetDLLPath) [0x0004c] in C:\buildslave\unity\build\Extensions\Networking\Weaver\UNetWeaver.cs:1888
5. UnityEngine.Debug:LogError(Object)
6. Unity.UNetWeaver.Log:Error(String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:20)
7. Unity.UNetWeaver.Weaver:WeaveAssemblies(IEnumerable`1, IEnumerable`1, IAssemblyResolver, String, String, String) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/UNetWeaver.cs:1896)
8. Unity.UNetWeaver.Program:Process(String, String, String, String[], String[], IAssemblyResolver, Action`1, Action`1) (at C:/buildslave/unity/build/Extensions/Networking/Weaver/Program.cs:34)

I don't have any networking code in my project. I tried launching Unity as administrator, but that didn't help.

 

That is due to a known bug with the new Incremental Compiler.
For now, the only fix is to manually patch the weaver to disable it.

Take a look at the Incremental Compiler Thread, there's info on there on how to workaround the issue if you're not using the weaver.