diff --git a/test/fixedbugs/bug506.dir/a.go b/test/fixedbugs/bug506.dir/a.go
new file mode 100644
index 00000000000..8e8a2005810
--- /dev/null
+++ b/test/fixedbugs/bug506.dir/a.go
@@ -0,0 +1,16 @@
+// Copyright 2018 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 a
+
+type internal struct {
+	f1 string
+	f2 float64
+}
+
+type S struct {
+	F struct {
+		I internal
+	}
+}
diff --git a/test/fixedbugs/bug506.dir/main.go b/test/fixedbugs/bug506.dir/main.go
new file mode 100644
index 00000000000..1b60e40d8d0
--- /dev/null
+++ b/test/fixedbugs/bug506.dir/main.go
@@ -0,0 +1,20 @@
+// Copyright 2018 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"
+
+	"./a"
+)
+
+var v = a.S{}
+
+func main() {
+	want := "{{ 0}}"
+	if got := fmt.Sprint(v.F); got != want {
+		panic(got)
+	}
+}
diff --git a/test/fixedbugs/bug506.go b/test/fixedbugs/bug506.go
new file mode 100644
index 00000000000..7c8ccc6ec7e
--- /dev/null
+++ b/test/fixedbugs/bug506.go
@@ -0,0 +1,10 @@
+// rundir
+
+// Copyright 2018 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.
+
+// Gccgo caused an undefined symbol reference building hash functions
+// for an imported struct with unexported fields.
+
+package ignored