7167069: 6 VM flags crash the VM when queried via jinfo

Summary: Added missing double format to Flag::print_as_flag()
Reviewed-by: dholmes, stefank, coleenp

src/share/vm/runtime/globals.cpp

@@ -148,6 +148,8 @@ void Flag::print_as_flag(outputStream* st) {
     st->print("-XX:%s=" UINTX_FORMAT, name, get_uintx());
   } else if (is_uint64_t()) {
     st->print("-XX:%s=" UINT64_FORMAT, name, get_uint64_t());
+  } else if (is_double()) {
+    st->print("-XX:%s=%f", name, get_double());
   } else if (is_ccstr()) {
     st->print("-XX:%s=", name);
     const char* cp = get_ccstr();

test/runtime/7167069/PrintAsFlag.java

+/*
+ * 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.
+ *
+ */
+
+/*
+ * Note that in the run command below the only important flag is PrintCommandLineFlags.
+ * The others are just flags of all types; bool, intx, uintx, uint64_t, double and ccstr.
+ *
+ * @test PrintAsFlag
+ * @summary verify that Flag::print_as_flag() works correctly. This is used by "jinfo -flag" and -XX:+PrintCommandLineFlags.
+ * @run main/othervm -XX:+PrintCommandLineFlags -XX:-ShowMessageBoxOnError -XX:BiasedLockingStartupDelay=4000 -XX:ParallelGCThreads=4 -XX:MaxRAM=1G -XX:CMSSmallCoalSurplusPercent=1.05 -XX:ErrorFile="file" PrintAsFlag
+ */
+
+public class PrintAsFlag {
+  public static void main(String... args) {
+    System.out.printf("Done");
+  }
+}