6956758: NPE in com.sun.tools.javac.code.Symbol - isSubClass

Use of TransTypes.cast() instead of TransTypes.coerce() causes NPE in Lower

Reviewed-by: jjg

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

@@ -719,7 +719,7 @@ public class TransTypes extends TreeTranslator {
                 tree.sym = ((MethodSymbol)tree.sym).
                     implemented((TypeSymbol)tree.sym.owner, types);
             }
-            tree.selected = cast(
+            tree.selected = coerce(
                 translate(tree.selected, erasure(tree.selected.type)),
                 erasure(tree.sym.owner.type));
         } else

langtools/test/tools/javac/generics/6956758/T6956758neg.java

@@ -0,0 +1,20 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 6956758
+ *
+ * @summary  NPE in com.sun.tools.javac.code.Symbol - isSubClass
+ * @author Maurizio Cimadamore
+ * @compile/fail/ref=T6956758neg.out -XDrawDiagnostics T6956758neg.java
+ *
+ */
+
+class T6956758neg {
+
+    interface I {}
+
+    static class C {
+        <T extends Object & I> T cloneObject(T object) throws Exception {
+            return (T)object.clone();
+        }
+    }
+}

langtools/test/tools/javac/generics/6956758/T6956758neg.out

@@ -0,0 +1,4 @@
+T6956758neg.java:17:29: compiler.err.report.access: clone(), protected, java.lang.Object
+- compiler.note.unchecked.filename: T6956758neg.java
+- compiler.note.unchecked.recompile
+1 error

langtools/test/tools/javac/generics/6956758/T6956758pos.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2010, 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 6956758
+ *
+ * @summary  NPE in com.sun.tools.javac.code.Symbol - isSubClass
+ * @author Maurizio Cimadamore
+ * @compile T6956758pos.java
+ *
+ */
+
+class T6956758pos {
+
+    interface I {}
+
+    static class C {
+        <T extends C & I> T cloneObject(T object) throws Exception {
+            return (T)object.clone();
+        }
+    }
+}