# System.Runtime.CompilerServices

``` diff
 namespace System.Runtime.CompilerServices {
+    public readonly struct ConfiguredAsyncDisposable {
+        public ConfiguredValueTaskAwaitable DisposeAsync();
+    }
     public static class RuntimeHelpers {
+        public static T[] GetSubArray<T>(T[] array, Range range);
     }
+    public sealed class SwitchExpressionException : InvalidOperationException {
+        public SwitchExpressionException();
+        public SwitchExpressionException(Exception innerException);
+        public SwitchExpressionException(object unmatchedValue);
+        public SwitchExpressionException(string message);
+        public SwitchExpressionException(string message, Exception innerException);
+        public object UnmatchedValue { get; }
+        public override void GetObjectData(SerializationInfo info, StreamingContext context);
+    }
 }
```

