diff --git a/runtime/vm.go b/runtime/vm.go
index 69e10664..07f6e530 100644
--- a/runtime/vm.go
+++ b/runtime/vm.go
@@ -859,9 +859,12 @@ func (v *VM) run() {
 			val := v.stack[v.sp-numSelectors-1]
 			v.sp -= numSelectors + 1
 
-			sp := v.curFrame.basePointer + localIndex
+			dst := v.stack[v.curFrame.basePointer+localIndex]
+			if obj, ok := dst.(*objects.ObjectPtr); ok {
+				dst = *obj.Value
+			}
 
-			if e := indexAssign(v.stack[sp], val, selectors); e != nil {
+			if e := indexAssign(dst, val, selectors); e != nil {
 				v.err = e
 				return
 			}
diff --git a/runtime/vm_function_test.go b/runtime/vm_function_test.go
index 820f8da9..9a481cd1 100644
--- a/runtime/vm_function_test.go
+++ b/runtime/vm_function_test.go
@@ -52,6 +52,16 @@ func TestFunction(t *testing.T) {
 	out = f2(10);
 	`, nil, 60)
 
+	expect(t, `
+		f1 := func(f) {
+			a := [undefined]
+			a[0] = func() { return f(a) }
+			return a[0]()
+		}
+
+		out = f1(func(a) { return 2 })
+	`, nil, 2)
+
 	// closures
 	expect(t, `
 		newAdder := func(x) {