diff -r 000000000000 -r 959103a6100f test/tools/javac/T6668802.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/tools/javac/T6668802.java	Wed Apr 27 01:34:52 2016 +0800
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2008, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 6668802
+ * @summary javac handles diagnostics for last line badly, if line not terminated by newline
+ */
+
+import java.io.*;
+import java.util.*;
+
+public class T6668802
+{
+    public static void main(String[] args) throws Exception {
+        new T6668802().run();
+    }
+
+    void run() throws Exception {
+        String test = "public class Test {";
+        File f = writeTestFile("Test.java", test);
+        String[] out = compileBadFile(f);
+        for (String line: out)
+            System.err.println(">>>" + line + "<<<");
+        if (!out[1].equals(test)) {
+            show("expected", test);
+            show("  actual", out[1]);
+            throw new Error("test failed");
+        }
+    }
+
+    File writeTestFile(String path, String contents) throws IOException {
+        File f = new File(path);
+        FileWriter out = new FileWriter(f);
+        out.write(contents);
+        out.close();
+        return f;
+    }
+
+    String[] compileBadFile(File file) throws IOException {
+        List<String> options = new ArrayList<String>();
+        options.add(file.getPath());
+        System.err.println("compile: " + options);
+        String[] opts = options.toArray(new String[options.size()]);
+        StringWriter sw = new StringWriter();
+        PrintWriter out = new PrintWriter(sw);
+        int rc = com.sun.tools.javac.Main.compile(opts, out);
+        if (rc == 0)
+            throw new Error("compilation succeeded unexpectedly");
+        out.close();
+        return sw.toString().split("[\n\r]+");
+    }
+
+    void show(String prefix, String text) {
+        System.err.println(prefix + ": (" + text.length() + ") " + text);
+    }
+}