Prevent static constructor from referencing DynamicDelegateLightup pr…

…ivate API in scenarios without app linking
ivanpovazan · Aug 14, 2023 · 6f8b3e8 · 6f8b3e8
1 parent 8984d9a
commit 6f8b3e8
Showing 1 changed file with 17 additions and 2 deletions.
diff --git a/src/libraries/System.Linq.Expressions/src/System/Dynamic/Utils/DelegateHelpers.cs b/src/libraries/System.Linq.Expressions/src/System/Dynamic/Utils/DelegateHelpers.cs
@@ -19,8 +19,23 @@ internal static class DelegateHelpers
         // with the Reflection.Emit statics below.
         private static class DynamicDelegateLightup
         {
-            public static Func<Type, Func<object?[], object?>, Delegate> CreateObjectArrayDelegate { get; }
-                = CreateObjectArrayDelegateInternal();
+            public static Func<Type, Func<object?[], object?>, Delegate> CreateObjectArrayDelegate
+            {
+                get
+                {
+                    // CreateObjectArrayDelegateInternal is only supported with NativeAOT which always expects CanEmitObjectArrayDelegate to be false.
+                    // Additionally, this check guards static constructor of trying to resolve 'Internal.Runtime.Augments.DynamicDelegateAugments'
+                    // on runtimes which do not support this private API, which would otherwise cause TypeInitializationException.
+                    if (!CanEmitObjectArrayDelegate)
+                    {
+                        return CreateObjectArrayDelegateInternal();
+                    }
+                    else
+                    {
+                        throw new System.NotImplementedException();
+                    }
+                }
+            }
 
             private static Func<Type, Func<object?[], object?>, Delegate> CreateObjectArrayDelegateInternal()
                 => Type.GetType("Internal.Runtime.Augments.DynamicDelegateAugments")!