--- /dev/null	2015-12-31 16:52:30.889242021 +0300
+++ new/test/tools/javac/TestIndyStringConcat.java	2016-01-15 13:30:59.439339924 +0300
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @summary Test that StringConcat is working for JDK >= 9
+ * @compile -source 6 -target 6 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat false
+ * @clean TestIndyStringConcat*
+ * @compile -source 7 -target 7 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat false
+ * @clean TestIndyStringConcat*
+ * @compile -source 8 -target 8 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat false
+ * @clean TestIndyStringConcat*
+ * @compile -XDstringConcat=inline -source 9 -target 9 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat false
+ * @clean TestIndyStringConcat*
+ * @compile -XDstringConcat=indy -source 9 -target 9 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat true
+ * @clean TestIndyStringConcat*
+ * @compile -XDstringConcat=indyWithConstants -source 9 -target 9 TestIndyStringConcat.java
+ * @run main TestIndyStringConcat true
+ */
+public class TestIndyStringConcat {
+
+    private static class MyObject {
+        public String toString() {
+            throw new RuntimeException("Boyyaa");
+        }
+    }
+
+    class Inner { }
+
+    public static void main(String[] args) {
+        boolean useIndyConcat = Boolean.valueOf(args[0]);
+        try {
+            String s = "Foo" + new MyObject();
+        } catch (RuntimeException ex) {
+            boolean indifiedStringConcat = false;
+            ex.printStackTrace();
+            for (StackTraceElement e : ex.getStackTrace()) {
+                if (e.getClassName().startsWith("java.lang.String$Concat") &&
+                        e.getMethodName().equals("concat")) {
+                    indifiedStringConcat = true;
+                    break;
+                }
+            }
+            if (indifiedStringConcat != useIndyConcat) {
+                throw new AssertionError();
+            }
+        }
+    }
+}