1 files changed, 3 insertions, 2 deletions
diff --git a/src/System.Private.CoreLib/shared/System/Threading/SynchronizationLockException.cs b/src/System.Private.CoreLib/shared/System/Threading/SynchronizationLockException.cs
index 3b5d31f3c0..fbd685afc9 100644
--- a/src/System.Private.CoreLib/shared/System/Threading/SynchronizationLockException.cs
+++ b/src/System.Private.CoreLib/shared/System/Threading/SynchronizationLockException.cs
@@ -12,6 +12,7 @@
 **
 =============================================================================*/
 
+#nullable enable
 using System.Runtime.Serialization;
 
 namespace System.Threading
@@ -26,13 +27,13 @@ namespace System.Threading
             HResult = HResults.COR_E_SYNCHRONIZATIONLOCK;
         }
 
-        public SynchronizationLockException(string message)
+        public SynchronizationLockException(string? message)
             : base(message)
         {
             HResult = HResults.COR_E_SYNCHRONIZATIONLOCK;
         }
 
-        public SynchronizationLockException(string message, Exception innerException)
+        public SynchronizationLockException(string? message, Exception? innerException)
             : base(message, innerException)
         {
             HResult = HResults.COR_E_SYNCHRONIZATIONLOCK;