1 files changed, 25 insertions, 0 deletions
diff --git a/test/fixedbugs/issue42568.go b/test/fixedbugs/issue42568.go
new file mode 100644
index 0000000..834fdc5
--- /dev/null
+++ b/test/fixedbugs/issue42568.go
@@ -0,0 +1,25 @@
+// compile
+
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Ensure that late expansion correctly handles an OpIData with type interface{}
+
+package p
+
+type S struct{}
+
+func (S) M() {}
+
+type I interface {
+	M()
+}
+
+func f(i I) {
+	o := i.(interface{})
+	if _, ok := i.(*S); ok {
+		o = nil
+	}
+	println(o)
+}