--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libgo/misc/cgo/test/issue9557.go	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,36 @@
+// Copyright 2015 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.
+
+// cgo rewrote C.var to *_Cvar_var, but left
+// C.var.field as _Cvar.var.field.  It now rewrites
+// the latter as (*_Cvar_var).field.
+// See https://golang.org/issue/9557.
+
+package cgotest
+
+// struct issue9557_t {
+//   int a;
+// } test9557bar = { 42 };
+//
+// struct issue9557_t *issue9557foo = &test9557bar;
+import "C"
+import "testing"
+
+func test9557(t *testing.T) {
+	// implicitly dereference a Go variable
+	foo := C.issue9557foo
+	if v := foo.a; v != 42 {
+		t.Fatalf("foo.a expected 42, but got %d", v)
+	}
+
+	// explicitly dereference a C variable
+	if v := (*C.issue9557foo).a; v != 42 {
+		t.Fatalf("(*C.issue9557foo).a expected 42, but is %d", v)
+	}
+
+	// implicitly dereference a C variable
+	if v := C.issue9557foo.a; v != 42 {
+		t.Fatalf("C.issue9557foo.a expected 42, but is %d", v)
+	}
+}