diff -r 000000000000 -r 959103a6100f test/tools/javac/scope/7017664/ImplementationCacheTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/tools/javac/scope/7017664/ImplementationCacheTest.java	Wed Apr 27 01:34:52 2016 +0800
@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2011, 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
+ * @bug 7017664
+ * @summary Basher for CompoundScopes
+ */
+
+import com.sun.source.util.JavacTask;
+import com.sun.tools.javac.code.Symbol;
+import com.sun.tools.javac.code.Types;
+import com.sun.tools.javac.file.JavacFileManager;
+import com.sun.tools.javac.util.Context;
+
+import com.sun.tools.javac.code.Symbol.*;
+
+import java.io.IOException;
+import java.net.URI;
+import java.util.Arrays;
+import java.util.List;
+import javax.lang.model.element.Element;
+import javax.tools.JavaCompiler;
+import javax.tools.JavaFileObject;
+import javax.tools.SimpleJavaFileObject;
+import javax.tools.ToolProvider;
+
+import static javax.tools.JavaFileObject.Kind;
+
+public class ImplementationCacheTest {
+
+    static class SourceFile extends SimpleJavaFileObject {
+
+        final String source = "interface I { void m(); }\n" +
+                              "class A implements I { public void m() {} }\n" +
+                              "class B extends A { }\n";
+
+        public SourceFile() {
+            super(URI.create("test.java"), Kind.SOURCE);
+        }
+
+        public CharSequence getCharContent(boolean ignoreEncodingErrors) {
+            return source;
+        }
+    }
+
+    public static void main(String[] args) throws IOException {
+        List<? extends JavaFileObject> files = Arrays.asList(new SourceFile());
+        JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
+        JavacTask ct = (JavacTask)tool.getTask(null, null, null, null, null, files);
+        Context ctx = new Context();
+        JavacFileManager.preRegister(ctx);
+        checkImplementationCache(ct.analyze(), Types.instance(ctx));
+    }
+
+    static void checkImplementationCache(Iterable<? extends Element> elements, Types types) {
+        if (types == null) {
+            throw new AssertionError("problems initializing Types");
+        }
+
+        Symbol a = null;
+        Symbol b = null;
+        Symbol i = null;
+
+        for (Element e : elements) {
+            if (e.getSimpleName().contentEquals("A")) {
+                a = (Symbol)e;
+            } else if (e.getSimpleName().contentEquals("B")) {
+                b = (Symbol)e;
+            } else if (e.getSimpleName().contentEquals("I")) {
+                i = (Symbol)e;
+            }
+        }
+
+        if (a == null || b == null || i == null) {
+            throw new AssertionError("missing class");
+        }
+
+        MethodSymbol I_m = null;
+
+        for (Symbol sym : i.members().getElements()) {
+            if (sym.name.contentEquals("m")) {
+                I_m = (MethodSymbol)sym;
+            }
+        }
+
+        if (I_m == null) {
+            throw new AssertionError("missing method m() in scope of interface I");
+        }
+
+        Symbol impl = I_m.implementation((TypeSymbol)b, types, true);
+
+        if (impl == null || impl.owner != a) {
+            throw new AssertionError("wrong implementation for m() in B");
+        }
+
+        b.members().enter(I_m.clone(b));
+
+        Symbol newImpl = I_m.implementation((TypeSymbol)b, types, true);
+
+        if (newImpl == impl) {
+            throw new AssertionError("stale implementation for m() in B");
+        }
+
+        if (newImpl == null || newImpl.owner != b) {
+            throw new AssertionError("wrong implementation for m() in B");
+        }
+    }
+}