1 files changed, 37 insertions, 0 deletions
diff --git a/test/typeparam/issue47740.go b/test/typeparam/issue47740.go
new file mode 100644
index 0000000000..a8c6839de3
--- /dev/null
+++ b/test/typeparam/issue47740.go
@@ -0,0 +1,37 @@
+// run -gcflags=-G=3
+
+// Copyright 2021 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.
+
+package main
+
+import "fmt"
+
+type Exp[Ty any] interface {
+	Eval() Ty
+}
+
+type Lit[Ty any] Ty
+
+func (lit Lit[Ty]) Eval() Ty       { return Ty(lit) }
+func (lit Lit[Ty]) String() string { return fmt.Sprintf("(lit %v)", Ty(lit)) }
+
+type Eq[Ty any] struct {
+	a Exp[Ty]
+	b Exp[Ty]
+}
+
+func (e Eq[Ty]) String() string {
+	return fmt.Sprintf("(eq %v %v)", e.a, e.b)
+}
+
+var (
+	e0 = Eq[int]{Lit[int](128), Lit[int](64)}
+	e1 = Eq[bool]{Lit[bool](true), Lit[bool](true)}
+)
+
+func main() {
+	fmt.Printf("%v\n", e0)
+	fmt.Printf("%v\n", e1)
+}