Assert failure in SetLoaderAllocator() when calling a DynamicMethod with collectible AssemblyLoadContext

[steveharter]

Using a checked runtime, the sample below fails with Assert in "_ASSERTE(pAllocator == GetLoaderAllocator())" in MethodTable::SetLoaderAllocator.

using System.Reflection;
using System.Reflection.Emit;
using System.Runtime.Loader;

namespace ConsoleApp1
{
    public class Program
    {
        static void Main()
        {
            string tempFilePath = Path.GetTempFileName() + ".dll";

            // Create a simple type; this doesn't need to be run in the same process for the Assert to fail.
            {
                PersistedAssemblyBuilder ab = new PersistedAssemblyBuilder(new AssemblyName("MyAssembly"), typeof(object).Assembly);
                TypeBuilder typeBuilder = ab.DefineDynamicModule("MyModule").DefineType("MyType", TypeAttributes.Public | TypeAttributes.Class);
                MethodBuilder myMethod = typeBuilder.DefineMethod("MyMethod", MethodAttributes.Public | MethodAttributes.Static, CallingConventions.Standard);
                ILGenerator ilGenerator = myMethod.GetILGenerator();
                ilGenerator.Emit(OpCodes.Ret);
                typeBuilder.CreateType();
                ab.Save(tempFilePath);
            }

            {
                TestAssemblyLoadContext tlc = new TestAssemblyLoadContext();

                Type typeFromDisk = tlc.LoadFromAssemblyPath(tempFilePath).GetType("MyType")!;
                // This also fails with the Assert (instead of above):
                //Type typeFromDisk = Assembly.LoadFrom(tempFilePath).GetType("MyType")!;

                MethodInfo methodFromDisk = typeFromDisk.GetMethod("MyMethod")!;

                DynamicMethod callIt = new DynamicMethod(
                    "CallIt",
                    MethodAttributes.Public | MethodAttributes.Static,
                    CallingConventions.Standard,
                    returnType: typeof(void),
                    parameterTypes: null,
                    m: typeFromDisk.Module, // Using typeof(object).Module works
                    skipVisibility: true);

                ILGenerator il = callIt.GetILGenerator();
                il.Emit(OpCodes.Call, methodFromDisk);
                il.Emit(OpCodes.Ret);

                Action invoker = (Action)callIt.CreateDelegate(typeof(Action));
 
                // This fails Assert in checked runtime "_ASSERTE(pAllocator == GetLoaderAllocator())" in MethodTable::SetLoaderAllocator:
                invoker();

                Console.WriteLine("Success");
                Console.ReadLine();
            }
        }
    }

    class TestAssemblyLoadContext : AssemblyLoadContext
    {
        public TestAssemblyLoadContext() : base(isCollectible: true) // Using "isCollectible : false" works
        {
        }
    }
}

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