Add `using System.Diagnostics.Private;` to Task-related sources

3 files changed, 5 insertions, 1 deletions

diff --git a/src/System.Private.CoreLib/src/System/Threading/Tasks/ConcurrentExclusiveSchedulerPair.cs b/src/System.Private.CoreLib/src/System/Threading/Tasks/ConcurrentExclusiveSchedulerPair.cs
index f7fbbac7b..7c155523e 100644
--- a/src/System.Private.CoreLib/src/System/Threading/Tasks/ConcurrentExclusiveSchedulerPair.cs
+++ b/src/System.Private.CoreLib/src/System/Threading/Tasks/ConcurrentExclusiveSchedulerPair.cs
@@ -17,6 +17,7 @@
 
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Diagnostics.Private;
 using System.Diagnostics.CodeAnalysis;
 
 namespace System.Threading.Tasks
@@ -712,7 +713,9 @@ namespace System.Threading.Tasks
         private static void ContractAssertMonitorStatus(Lock syncObj, bool held)
         {
             Debug.Assert(syncObj != null, "The Lock object to check must be provided.");
+#if !MONO
             Debug.Assert(syncObj.IsAcquired == held, "The locking scheme was not correctly followed.");
+#endif
         }
 
         /// <summary>Gets the options to use for tasks.</summary>
diff --git a/src/System.Private.CoreLib/src/System/Threading/Tasks/TaskExceptionHolder.cs b/src/System.Private.CoreLib/src/System/Threading/Tasks/TaskExceptionHolder.cs
index f06b0750c..e915f3595 100644
--- a/src/System.Private.CoreLib/src/System/Threading/Tasks/TaskExceptionHolder.cs
+++ b/src/System.Private.CoreLib/src/System/Threading/Tasks/TaskExceptionHolder.cs
@@ -18,6 +18,7 @@
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Diagnostics;
+using System.Diagnostics.Private;
 using System.Runtime.ExceptionServices;
 
 namespace System.Threading.Tasks
diff --git a/src/System.Private.Interop/src/InteropExtensions/Lock.cs b/src/System.Private.Interop/src/InteropExtensions/Lock.cs
index d86c28f12..e252ea985 100644
--- a/src/System.Private.Interop/src/InteropExtensions/Lock.cs
+++ b/src/System.Private.Interop/src/InteropExtensions/Lock.cs
@@ -10,7 +10,7 @@ namespace System.Threading
     /// Simple wrapper around Monitor.Enter and Exit exposing interface as expected by 
     /// System.Private.InteropServices.__ComObject
     /// </summary>
-    public class Lock
+    public partial class Lock
     {
         private object _lock = new object();
         public void Acquire()