--- /dev/null 2017-02-28 23:59:25.000000000 +0300 +++ new/test/compiler/c1/VolatileGuardTest.java 2017-02-28 23:59:24.000000000 +0300 @@ -0,0 +1,52 @@ +/* + * Copyright (c) 2017, Red Hat Inc. 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 8175887 + * @summary C1 doesn't respect the JMM with volatile field loads + * + * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:TieredStopAtLevel=1 VolatileGuardTest + */ +public class VolatileGuardTest { + volatile static private int a; + static private int b; + + static void test() { + int tt = b; // makes the JVM CSE the value of b + + while (a == 0) {} // burn + if (b == 0) { + System.err.println("wrong value of b"); + System.exit(1); // fail hard to report the error + } + } + + public static void main(String [] args) throws Exception { + for (int i = 0; i < 10; i++) { + new Thread(VolatileGuardTest::test).start(); + } + b = 1; + a = 1; + } +}