7166990: java/compiler Inherited interfaces using generics sometimes looses the generic type

Reviewed-by: mcimadamore

langtools/src/share/classes/com/sun/tools/javac/comp/Lower.java

@@ -1606,6 +1606,11 @@ public class Lower extends TreeTranslator {
     }
 
     private JCStatement makeResourceCloseInvocation(JCExpression resource) {
+        // convert to AutoCloseable if needed
+        if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) {
+            resource = (JCExpression) convert(resource, syms.autoCloseableType);
+        }
+
         // create resource.close() method invocation
         JCExpression resourceClose = makeCall(resource,
                                               names.close,

langtools/test/tools/javac/TryWithResources/T7164542.java

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2012, 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 7164542
+ * @summary try-with-resources: problem with intersection types
+ * @compile T7164542.java
+ */
+
+public class T7164542 {
+    public static <S extends Readable & AutoCloseable,
+                       T extends Appendable & AutoCloseable>
+    void copy(S s, T t, int size) throws Exception {
+        /*
+         * compiler used to fail here with:
+         *     symbol:   method close()
+         *     location: interface Readable
+         *     Fatal Error: Unable to find method close
+         */
+        try (S src = s; T trg = t) {
+        }
+    }
+}