NativeAOT: GVM that requires runtime lookup but doesn't override the base method won't compile

[hez2010]

Repro1:

RuntimeLookupDelegateGenericVirtual.Test<string>();

internal class RuntimeLookupDelegateGenericVirtual
{
 internal static void Test<T>()
 {
 var test2 = new Derived();
 Delegate m1 = test2.Foo<List<T>>();
 Delegate m2 = test2.Foo<List<List<T>>>;
 if (m1.Method != m2.Method)
 {
 throw new Exception($"Unexpected different methods returned from generic virtual method.");
 }
 }
}

internal interface Base
{
 public virtual Delegate Foo<U>()
 {
 return Foo<U>;
 }
}

internal struct Derived : Base
{
 public Delegate Foo<U1>()
 {
 return Foo<List<U1>>;
 }
}

Repro2 (changing the struct to class):

RuntimeLookupDelegateGenericVirtual.Test<string>();

internal class RuntimeLookupDelegateGenericVirtual
{
 internal static void Test<T>()
 {
 var test2 = new Derived();
 Delegate m1 = test2.Foo<List<T>>();
 Delegate m2 = test2.Foo<List<List<T>>>;
 if (m1.Method != m2.Method)
 {
 throw new Exception($"Unexpected different methods returned from generic virtual method.");
 }
 }
}

internal interface Base
{
 public virtual Delegate Foo<U>()
 {
 return Foo<U>;
 }
}

internal class Derived : Base
{
 public Delegate Foo<U1>()
 {
 return Foo<List<U1>>;
 }
}

Repro3 (changing the interface to a base class, but don't override the method in derived class):

RuntimeLookupDelegateGenericVirtual.Test<string>();

internal class RuntimeLookupDelegateGenericVirtual
{
 internal static void Test<T>()
 {
 var test2 = new Derived();
 Delegate m1 = test2.Foo<List<T>>();
 Delegate m2 = test2.Foo<List<List<T>>>;
 if (m1.Method != m2.Method)
 {
 throw new Exception($"Unexpected different methods returned from generic virtual method.");
 }
 }
}

internal class Base
{
 public virtual Delegate Foo<U>()
 {
 return Foo<U>;
 }
}

internal class Derived : Base
{
 public new Delegate Foo<U1>()
 {
 return Foo<List<U1>>;
 }
}

Ilc will never complete compiling the above snippets and will stick there forever.

It only compiles when you are overriding the base method of a class.

RuntimeLookupDelegateGenericVirtual.Test<string>();

internal class RuntimeLookupDelegateGenericVirtual
{
 internal static void Test<T>()
 {
 var test2 = new Derived();
 Delegate m1 = test2.Foo<List<T>>();
 Delegate m2 = test2.Foo<List<List<T>>>;
 if (m1.Method != m2.Method)
 {
 throw new Exception($"Unexpected different methods returned from generic virtual method.");
 }
 }
}

internal class Base
{
 public virtual Delegate Foo<U>()
 {
 return Foo<U>;
 }
}

internal class Derived : Base
{
 public override Delegate Foo<U1>()
 {
 return Foo<List<U1>>;
 }
}

cc: @MichalStrehovsky

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