8321479: java -D-D crashes

Reviewed-by: dholmes
Backport-of: dcdcd48d8fbf076e12841e557ebbe70228c8a92b

src/hotspot/share/runtime/arguments.cpp

@@ -315,7 +315,6 @@ static bool matches_property_suffix(const char* option, const char* property, si
 // any of the reserved module properties.
 // property should be passed without the leading "-D".
 bool Arguments::is_internal_module_property(const char* property) {
-  assert((strncmp(property, "-D", 2) != 0), "Unexpected leading -D");
   if  (strncmp(property, MODULE_PROPERTY_PREFIX, MODULE_PROPERTY_PREFIX_LEN) == 0) {
     const char* property_suffix = property + MODULE_PROPERTY_PREFIX_LEN;
     if (matches_property_suffix(property_suffix, ADDEXPORTS, ADDEXPORTS_LEN) ||

test/hotspot/jtreg/runtime/CommandLine/UnrecognizedProperty.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2023, 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 8321479
+ * @summary VM should not crash with property "-D-D"
+ * @requires vm.flagless
+ * @library /test/lib
+ * @run driver UnrecognizedProperty
+ */
+
+import jdk.test.lib.process.ProcessTools;
+import jdk.test.lib.process.OutputAnalyzer;
+
+public class UnrecognizedProperty {
+    public static void main(String[] args) throws Exception {
+        ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder(
+            "-D-D");
+
+        OutputAnalyzer output = new OutputAnalyzer(pb.start());
+        output.shouldContain("Usage: java");
+        output.shouldHaveExitValue(1);
+    }
+}