8033437: javac, inconsistent generic types behaviour when compiling together vs. separate

Reviewed-by: jjg
Contributed-by: vicente.romero@oracle.com, paul.govereau@oracle.com

src/share/classes/com/sun/tools/javac/code/Types.java

@@ -3972,8 +3972,13 @@ public class Types {
                     Si.lower = Ti.getSuperBound();
                     break;
                 }
-                if (Si.bound == Si.lower)
+                Type tmpBound = Si.bound.hasTag(UNDETVAR) ? ((UndetVar)Si.bound).qtype : Si.bound;
+                Type tmpLower = Si.lower.hasTag(UNDETVAR) ? ((UndetVar)Si.lower).qtype : Si.lower;
+                if (!Si.bound.hasTag(ERROR) &&
+                    !Si.lower.hasTag(ERROR) &&
+                    isSameType(tmpBound, tmpLower, false)) {
                     currentS.head = Si.bound;
+                }
             }
             currentA = currentA.tail;
             currentT = currentT.tail;

test/tools/javac/generics/wildcards/RefQueue.java

+/*
+ * Copyright (c) 2014, 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.
+ */
+
+public class RefQueue<S> { }

test/tools/javac/generics/wildcards/RefQueueBug.java

+/*
+ * Copyright (c) 2014, 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 8033437
+ * @summary inconsistent generic types behaviour when compiling together vs. separate
+ * @compile RefQueue.java
+ * @compile RefQueueBug.java
+ */
+
+public class RefQueueBug<T> {
+    final RefQueue<? super T> queue = new RefQueue<>();
+    public static void main(String[] args) {
+        RefQueueBug<Object> r = new RefQueueBug<>();
+        RefQueue<Object> q = r.queue;
+    }
+}