--- a/src/java.xml/share/classes/com/sun/org/apache/xerces/internal/impl/XMLDocumentScannerImpl.java	Fri Feb 10 12:28:08 2017 +0000
+++ b/src/java.xml/share/classes/com/sun/org/apache/xerces/internal/impl/XMLDocumentScannerImpl.java	Tue Feb 14 10:28:12 2017 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
  */
 
 /*
@@ -743,7 +743,7 @@
             // scan XMLDecl
             try {
                 if (fEntityScanner.skipString(XMLDECL)) {
-                    if (fEntityScanner.peekChar() == ' ') {
+                    if (XMLChar.isSpace(fEntityScanner.peekChar())) {
                         fMarkupDepth++;
                         scanXMLDeclOrTextDecl(false);
                     } else {

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/javax/xml/jaxp/unittest/parsers/BaseParsingTest.java	Tue Feb 14 10:28:12 2017 -0800
@@ -0,0 +1,158 @@
+/*
+ * Copyright (c) 2017, 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.
+ */
+package parsers;
+
+import java.io.StringReader;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLStreamReader;
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Listeners;
+import org.testng.annotations.Test;
+import org.xml.sax.InputSource;
+
+/**
+ * @test
+ * @bug 8169450
+ * @library /javax/xml/jaxp/libs /javax/xml/jaxp/unittest
+ * @run testng/othervm -DrunSecMngr=true parsers.BaseParsingTest
+ * @run testng/othervm parsers.BaseParsingTest
+ * @summary Tests that verify base parsing
+ */
+@Listeners({jaxp.library.BasePolicy.class})
+public class BaseParsingTest {
+
+    @DataProvider(name = "xmlDeclarations")
+    public static Object[][] xmlDeclarations() {
+        return new Object[][]{
+            {"<?xml version=\"1.0\"?><root><test>t</test></root>"},
+            {"<?xml version=\"1.0\" encoding=\"UTF-8\"?><root><test>t</test></root>"},
+            {"<?xml version=\"1.0\" encoding=\"UTF-8\" standalone='yes'?><root><test>t</test></root>"},
+            {"<?xml\n"
+                + " version=\"1.0\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version=\"1.0\"\n"
+                + " encoding=\"UTF-8\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version=\"1.0\"\n"
+                + " encoding=\"UTF-8\"\n"
+                + " standalone=\"yes\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version\n"
+                + "=\n"
+                + "\"1.0\"\n"
+                + " encoding\n"
+                + "=\n"
+                + "\"UTF-8\"\n"
+                + " standalone\n"
+                + "=\n"
+                + "\"yes\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml version=\"1.1\"?><root><test>t</test></root>"},
+            {"<?xml version=\"1.1\" encoding=\"UTF-8\"?><root><test>t</test></root>"},
+            {"<?xml version=\"1.1\" encoding=\"UTF-8\" standalone='yes'?><root><test>t</test></root>"},
+            {"<?xml\n"
+                + " version=\"1.1\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version=\"1.1\"\n"
+                + " encoding=\"UTF-8\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version=\"1.1\"\n"
+                + " encoding=\"UTF-8\"\n"
+                + " standalone=\"yes\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"},
+            {"<?xml\n"
+                + " version\n"
+                + "=\n"
+                + "\"1.1\"\n"
+                + " encoding\n"
+                + "=\n"
+                + "\"UTF-8\"\n"
+                + " standalone\n"
+                + "=\n"
+                + "\"yes\"?>\n"
+                + "<root>\n"
+                + " <test>t</test>\n"
+                + "</root>"}
+        };
+    }
+
+    /**
+     * @bug 8169450
+     * Verifies that the parser successfully parses the declarations provided in
+     * xmlDeclarations. Exception would otherwise be thrown as reported in 8169450.
+     *
+     * XML Declaration according to https://www.w3.org/TR/REC-xml/#NT-XMLDecl
+     * [23] XMLDecl     ::= '<?xml' VersionInfo EncodingDecl? SDDecl? S? '?>'
+     * [24] VersionInfo ::= S 'version' Eq ("'" VersionNum "'" | '"' VersionNum '"')
+     * [25] Eq          ::= S? '=' S? [26] VersionNum ::= '1.' [0-9]+
+     *
+     * @param xml the test xml
+     * @throws Exception if the parser fails to parse the xml
+     */
+    @Test(dataProvider = "xmlDeclarations")
+    public void test(String xml) throws Exception {
+        XMLInputFactory xif = XMLInputFactory.newDefaultFactory();
+        XMLStreamReader xsr = xif.createXMLStreamReader(new StringReader(xml));
+        while (xsr.hasNext()) {
+            xsr.next();
+        }
+    }
+
+    /**
+     * @bug 8169450
+     * This particular issue does not appear in DOM parsing since the spaces are
+     * normalized during version detection. This test case then serves as a guard
+     * against such an issue from occuring in the version detection.
+     *
+     * @param xml the test xml
+     * @throws Exception if the parser fails to parse the xml
+     */
+    @Test(dataProvider = "xmlDeclarations")
+    public void testWithDOM(String xml) throws Exception {
+        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
+        dbf.setValidating(true);
+        DocumentBuilder db = dbf.newDocumentBuilder();
+        db.parse(new InputSource(new StringReader(xml)));
+    }
+}