8164399: inference of thrown variable does not work correctly

Logic for inferring thrown variables should exclude non proper bounds as per JLS 18.1

Reviewed-by: vromero, dlsmith

langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Infer.java

@@ -61,6 +61,7 @@ import java.util.Properties;
 import java.util.Set;
 import java.util.function.BiFunction;
 import java.util.function.BiPredicate;
+import java.util.stream.Collectors;
 
 import com.sun.tools.javac.main.Option;
 
@@ -1475,16 +1476,11 @@ public class Infer {
                     //not a throws undet var
                     return false;
                 }
-                Infer infer = inferenceContext.infer;
-                for (Type db : t.getBounds(InferenceBound.UPPER)) {
-                    if (t.isInterface()) continue;
-                    if (infer.types.asSuper(infer.syms.runtimeExceptionType, db.tsym) == null) {
-                        //upper bound is not a supertype of RuntimeException - give up
-                        return false;
-                    }
-                }
-
-                return true;
+                Types types = inferenceContext.types;
+                Symtab syms = inferenceContext.infer.syms;
+                return t.getBounds(InferenceBound.UPPER).stream()
+                        .filter(b -> !inferenceContext.free(b))
+                        .allMatch(u -> types.isSubtype(syms.runtimeExceptionType, u));
             }
 
             @Override

langtools/test/tools/javac/generics/inference/8164399/T8164399.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2016, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 8164399
+ * @summary inference of thrown variable does not work correctly
+ * @compile T8164399.java
+ */
+
+abstract class T8164399 {
+
+    interface ThrowableRunnable<E extends Throwable> {
+       void compute() throws E;
+    }
+
+    public abstract < E extends Exception> void computeException(ThrowableRunnable<E> process) throws E;
+
+
+    public static <T, E extends Throwable> T compute(ThrowableRunnable<E> action) throws E {
+        return null;
+    }
+
+    {
+        computeException(() -> compute(() -> {}));
+    }
+}

langtools/test/tools/javac/generics/inference/8164399/T8164399b.java

@@ -0,0 +1,21 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 8164399
+ * @summary inference of thrown variable does not work correctly
+ * @compile/fail/ref=T8164399b.out -XDrawDiagnostics T8164399b.java
+ */
+class T8164399b<X extends Throwable> {
+    <T extends Throwable> void m(Class<? super T> arg) throws T {}
+    <T extends X> void g() throws T {}
+
+    void test() {
+        m(RuntimeException.class); // ok
+        m(Exception.class); // error
+        m(Throwable.class); // ok
+        m(java.io.Serializable.class); // error
+        m(Object.class); // error
+        m(Runnable.class); // error
+        T8164399b<? super Exception> x = null;
+        x.g(); // expected: ok; actual: error
+    }
+}

langtools/test/tools/javac/generics/inference/8164399/T8164399b.out

@@ -0,0 +1,2 @@
+T8164399b.java:17:10: compiler.err.unreported.exception.need.to.catch.or.throw: java.lang.Throwable&java.lang.Runnable
+1 error