}

	// instantiated type should point to itself
	if p := res.Underlying().(*Pointer).Elem(); p != res {
		t.Fatalf("unexpected result type: %s points to %s", res, p)
	}
}

func TestInstantiateConcurrent(t *testing.T) {
	const src = `package p

type I[P any] interface {
	m(P)
	n() P
}

type J = I[int]

type Nested[P any] *interface{b(P)}

type K = Nested[string]

	}

	// instantiated type should point to itself
	if p := res.Underlying().(*Pointer).Elem(); p != res {
		t.Fatalf("unexpected result type: %s points to %s", res, p)
	}
}

func TestInstantiateConcurrent(t *testing.T) {
	const src = `package p

type I[P any] interface {
	m(P)
	n() P
}

type J = I[int]

type Nested[P any] *interface{b(P)}

type K = Nested[string]