--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/langtools/tools/javac/lambda/deduplication/Deduplication.java	Tue Mar 27 13:48:16 2018 -0400
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2018, Google LLC. 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.
+ */
+
+package com.sun.tools.javac.comp;
+
+import java.util.function.BiFunction;
+import java.util.function.Consumer;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+public class Deduplication {
+    void group(Object... xs) {}
+
+    void test() {
+        group((Function<String, Integer>) x -> x.hashCode());
+        group((Function<Object, Integer>) x -> x.hashCode());
+
+        {
+            int x = 1;
+            group((Supplier<Integer>) () -> x + 1);
+        }
+        {
+            int x = 1;
+            group((Supplier<Integer>) () -> x + 1);
+        }
+        group(
+                (BiFunction<Integer, Integer, ?>) (x, y) -> x + ((y)),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> x + (y),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> x + y,
+                (BiFunction<Integer, Integer, ?>) (x, y) -> (x) + ((y)),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> (x) + (y),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> (x) + y,
+                (BiFunction<Integer, Integer, ?>) (x, y) -> ((x)) + ((y)),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> ((x)) + (y),
+                (BiFunction<Integer, Integer, ?>) (x, y) -> ((x)) + y);
+
+        group(
+                (Function<Integer, Integer>) x -> x + (1 + 2 + 3),
+                (Function<Integer, Integer>) x -> x + 6);
+
+        group((Function<Integer, Integer>) x -> x + 1, (Function<Integer, Integer>) y -> y + 1);
+
+        group((Consumer<Integer>) x -> this.f(), (Consumer<Integer>) x -> this.f());
+
+        group((Consumer<Integer>) y -> this.g());
+
+        group((Consumer<Integer>) x -> f(), (Consumer<Integer>) x -> f());
+
+        group((Consumer<Integer>) y -> g());
+
+        group((Function<Integer, Integer>) x -> this.i, (Function<Integer, Integer>) x -> this.i);
+
+        group((Function<Integer, Integer>) y -> this.j);
+
+        group((Function<Integer, Integer>) x -> i, (Function<Integer, Integer>) x -> i);
+
+        group((Function<Integer, Integer>) y -> j);
+
+        group(
+                (Function<Integer, Integer>) y -> {
+                        while (true) {
+                              break;
+                        }
+                        return 42;
+                },
+                (Function<Integer, Integer>) y -> {
+                        while (true) {
+                              break;
+                        }
+                        return 42;
+                });
+
+        class Local {
+            int i;
+
+            void f() {}
+
+            {
+                group((Function<Integer, Integer>) x -> this.i);
+                group((Consumer<Integer>) x -> this.f());
+                group((Function<Integer, Integer>) x -> Deduplication.this.i);
+                group((Consumer<Integer>) x -> Deduplication.this.f());
+            }
+        }
+    }
+
+    void f() {}
+
+    void g() {}
+
+    int i;
+    int j;
+}