NullReferenceException in CSC task
C:\Tools.csproj(58,3): error MSB4018: The "Csc" task failed unexpectedly.
C:\Tools.csproj(58,3): error MSB4018: System.NullReferenceException: Object reference not set to an instance of an object.
C:\Tools.csproj(58,3): error MSB4018: at Microsoft.Build.Tasks.ManagedCompiler.CheckAllReferencesExistOnDisk()
C:\Tools.csproj(58,3): error MSB4018: at Microsoft.Build.Tasks.Csc.InitializeHostObject(Boolean& appropriateHostObjectExists, Boolean& continueBuild)
C:\Tools.csproj(58,3): error MSB4018: at Microsoft.Build.Utilities.ToolTask.Execute()
C:\Tools.csproj(58,3): error MSB4018: at Microsoft.Build.BuildEngine.TaskEngine.ExecuteTask(ExecutionMode howToExecuteTask, Hashtable projectItemsAvailableToTask, BuildPropertyGroup projectPropertiesAvailableToTask)
Done building project "Tools.csproj" -- FAILED.
BTW, this is in a custom .csproj file (and custom .targets file). I'm just trying to get VS to host my custom MSBuild project file.
