src/share/vm/services/attachListener.cpp

@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 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.

@@ -269,18 +269,22 @@
 }
 
 // set a uintx global flag using value from AttachOperation
 static jint set_uintx_flag(const char* name, AttachOperation* op, outputStream* out) {
   uintx value;
-  const char* arg1;
-  if ((arg1 = op->arg(1)) != NULL) {
+
+  const char* arg1 = op->arg(1);
+  if (arg1 == NULL) {
+    out->print_cr("flag value must be specified");
+    return JNI_ERR;
+  }
+
     int n = sscanf(arg1, UINTX_FORMAT, &value);
     if (n != 1) {
       out->print_cr("flag value must be an unsigned integer");
       return JNI_ERR;
     }
-  }
 
   if (strncmp(name, "MaxHeapFreeRatio", 17) == 0) {
     FormatBuffer<80> err_msg("%s", "");
     if (!Arguments::verify_MaxHeapFreeRatio(err_msg, value)) {
       out->print_cr("%s", err_msg.buffer());