diff -r 000000000000 -r 9a66ca7c79fa test/tools/javac/T6366196.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/tools/javac/T6366196.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2006 Sun Microsystems, 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug     6359661 6366196
+ * @summary Unit test for corner cases of position encoding
+ * @author  Wei Tao
+ * @run main T6366196
+ */
+
+import com.sun.tools.javac.util.*;
+
+public class T6366196 {
+    public static final int MIDLINE = Position.MAXPOS>>>Position.LINESHIFT; // 0x00200000
+
+    public static void main(String[] args) {
+        positiveTest(10, Position.MAXCOLUMN);
+        negativeTest(20, Position.MAXCOLUMN + 1);
+        positiveTest(MIDLINE, Position.MAXCOLUMN);
+        positiveTest(Position.MAXLINE, 40);
+        negativeTest(Position.MAXLINE, Position.MAXCOLUMN);
+        negativeTest(Position.MAXLINE + 1, 1);
+    }
+
+    public static void positiveTest(int line, int col) {
+        if (Position.encodePosition(line, col) == Position.NOPOS) {
+            throw new Error("test failed at line = " + line + ", column = " + col);
+        } else {
+            System.out.println("test passed at line = " + line + ", column = " + col);
+        }
+    }
+
+    public static void negativeTest(int line, int col) {
+        if (Position.encodePosition(line, col) != Position.NOPOS) {
+            throw new Error("test failed at line = " + line + ", column = " + col);
+        } else {
+            System.out.println("test passed at line = " + line + ", column = " + col);
+        }
+    }
+}