diff --git a/src/test/regress/expected/xml_2.out b/src/test/regress/expected/xml_2.out
new file mode 100644
index 00000000000..5fda7ec2353
--- /dev/null
+++ b/src/test/regress/expected/xml_2.out
@@ -0,0 +1,719 @@
+CREATE TABLE xmltest (
+    id int,
+    data xml
+);
+INSERT INTO xmltest VALUES (1, '<value>one</value>');
+INSERT INTO xmltest VALUES (2, '<value>two</value>');
+INSERT INTO xmltest VALUES (3, '<wrong');
+ERROR:  invalid XML content
+LINE 1: INSERT INTO xmltest VALUES (3, '<wrong');
+                                       ^
+DETAIL:  Entity: line 1: parser error : Couldn't find end of Start Tag wrong line 1
+SELECT * FROM xmltest;
+ id |        data        
+----+--------------------
+  1 | <value>one</value>
+  2 | <value>two</value>
+(2 rows)
+
+SELECT xmlcomment('test');
+ xmlcomment  
+-------------
+ <!--test-->
+(1 row)
+
+SELECT xmlcomment('-test');
+  xmlcomment  
+--------------
+ <!---test-->
+(1 row)
+
+SELECT xmlcomment('test-');
+ERROR:  invalid XML comment
+SELECT xmlcomment('--test');
+ERROR:  invalid XML comment
+SELECT xmlcomment('te st');
+  xmlcomment  
+--------------
+ <!--te st-->
+(1 row)
+
+SELECT xmlconcat(xmlcomment('hello'),
+                 xmlelement(NAME qux, 'foo'),
+                 xmlcomment('world'));
+               xmlconcat                
+----------------------------------------
+ <!--hello--><qux>foo</qux><!--world-->
+(1 row)
+
+SELECT xmlconcat('hello', 'you');
+ xmlconcat 
+-----------
+ helloyou
+(1 row)
+
+SELECT xmlconcat(1, 2);
+ERROR:  argument of XMLCONCAT must be type xml, not type integer
+LINE 1: SELECT xmlconcat(1, 2);
+                         ^
+SELECT xmlconcat('bad', '<syntax');
+ERROR:  invalid XML content
+LINE 1: SELECT xmlconcat('bad', '<syntax');
+                                ^
+DETAIL:  Entity: line 1: parser error : Couldn't find end of Start Tag syntax line 1
+SELECT xmlconcat('<foo/>', NULL, '<?xml version="1.1" standalone="no"?><bar/>');
+  xmlconcat   
+--------------
+ <foo/><bar/>
+(1 row)
+
+SELECT xmlconcat('<?xml version="1.1"?><foo/>', NULL, '<?xml version="1.1" standalone="no"?><bar/>');
+             xmlconcat             
+-----------------------------------
+ <?xml version="1.1"?><foo/><bar/>
+(1 row)
+
+SELECT xmlconcat(NULL);
+ xmlconcat 
+-----------
+ 
+(1 row)
+
+SELECT xmlconcat(NULL, NULL);
+ xmlconcat 
+-----------
+ 
+(1 row)
+
+SELECT xmlelement(name element,
+                  xmlattributes (1 as one, 'deuce' as two),
+                  'content');
+                   xmlelement                   
+------------------------------------------------
+ <element one="1" two="deuce">content</element>
+(1 row)
+
+SELECT xmlelement(name element,
+                  xmlattributes ('unnamed and wrong'));
+ERROR:  unnamed XML attribute value must be a column reference
+LINE 2:                   xmlattributes ('unnamed and wrong'));
+                                         ^
+SELECT xmlelement(name element, xmlelement(name nested, 'stuff'));
+                xmlelement                 
+-------------------------------------------
+ <element><nested>stuff</nested></element>
+(1 row)
+
+SELECT xmlelement(name employee, xmlforest(name, age, salary as pay)) FROM emp;
+                              xmlelement                              
+----------------------------------------------------------------------
+ <employee><name>sharon</name><age>25</age><pay>1000</pay></employee>
+ <employee><name>sam</name><age>30</age><pay>2000</pay></employee>
+ <employee><name>bill</name><age>20</age><pay>1000</pay></employee>
+ <employee><name>jeff</name><age>23</age><pay>600</pay></employee>
+ <employee><name>cim</name><age>30</age><pay>400</pay></employee>
+ <employee><name>linda</name><age>19</age><pay>100</pay></employee>
+(6 rows)
+
+SELECT xmlelement(name duplicate, xmlattributes(1 as a, 2 as b, 3 as a));
+ERROR:  XML attribute name "a" appears more than once
+LINE 1: ...ment(name duplicate, xmlattributes(1 as a, 2 as b, 3 as a));
+                                                              ^
+SELECT xmlelement(name num, 37);
+  xmlelement   
+---------------
+ <num>37</num>
+(1 row)
+
+SELECT xmlelement(name foo, text 'bar');
+   xmlelement   
+----------------
+ <foo>bar</foo>
+(1 row)
+
+SELECT xmlelement(name foo, xml 'bar');
+   xmlelement   
+----------------
+ <foo>bar</foo>
+(1 row)
+
+SELECT xmlelement(name foo, text 'b<a/>r');
+       xmlelement        
+-------------------------
+ <foo>b&lt;a/&gt;r</foo>
+(1 row)
+
+SELECT xmlelement(name foo, xml 'b<a/>r');
+    xmlelement     
+-------------------
+ <foo>b<a/>r</foo>
+(1 row)
+
+SELECT xmlelement(name foo, array[1, 2, 3]);
+                               xmlelement                                
+-------------------------------------------------------------------------
+ <foo><element>1</element><element>2</element><element>3</element></foo>
+(1 row)
+
+SET xmlbinary TO base64;
+SELECT xmlelement(name foo, bytea 'bar');
+   xmlelement    
+-----------------
+ <foo>YmFy</foo>
+(1 row)
+
+SET xmlbinary TO hex;
+SELECT xmlelement(name foo, bytea 'bar');
+    xmlelement     
+-------------------
+ <foo>626172</foo>
+(1 row)
+
+SELECT xmlelement(name foo, xmlattributes(true as bar));
+    xmlelement     
+-------------------
+ <foo bar="true"/>
+(1 row)
+
+SELECT xmlelement(name foo, xmlattributes('2009-04-09 00:24:37'::timestamp as bar));
+            xmlelement            
+----------------------------------
+ <foo bar="2009-04-09T00:24:37"/>
+(1 row)
+
+SELECT xmlelement(name foo, xmlattributes('infinity'::timestamp as bar));
+ERROR:  timestamp out of range
+DETAIL:  XML does not support infinite timestamp values.
+SELECT xmlelement(name foo, xmlattributes('<>&"''' as funny, xml 'b<a/>r' as funnier));
+                         xmlelement                         
+------------------------------------------------------------
+ <foo funny="&lt;&gt;&amp;&quot;'" funnier="b&lt;a/&gt;r"/>
+(1 row)
+
+SELECT xmlparse(content 'abc');
+ xmlparse 
+----------
+ abc
+(1 row)
+
+SELECT xmlparse(content '<abc>x</abc>');
+   xmlparse   
+--------------
+ <abc>x</abc>
+(1 row)
+
+SELECT xmlparse(document 'abc');
+ERROR:  invalid XML document
+DETAIL:  Entity: line 1: parser error : Start tag expected, '<' not found
+abc
+^
+SELECT xmlparse(document '<abc>x</abc>');
+   xmlparse   
+--------------
+ <abc>x</abc>
+(1 row)
+
+SELECT xmlpi(name foo);
+  xmlpi  
+---------
+ <?foo?>
+(1 row)
+
+SELECT xmlpi(name xml);
+ERROR:  invalid XML processing instruction
+DETAIL:  XML processing instruction target name cannot be "xml".
+SELECT xmlpi(name xmlstuff);
+    xmlpi     
+--------------
+ <?xmlstuff?>
+(1 row)
+
+SELECT xmlpi(name foo, 'bar');
+    xmlpi    
+-------------
+ <?foo bar?>
+(1 row)
+
+SELECT xmlpi(name foo, 'in?>valid');
+ERROR:  invalid XML processing instruction
+DETAIL:  XML processing instruction cannot contain "?>".
+SELECT xmlpi(name foo, null);
+ xmlpi 
+-------
+ 
+(1 row)
+
+SELECT xmlpi(name xml, null);
+ERROR:  invalid XML processing instruction
+DETAIL:  XML processing instruction target name cannot be "xml".
+SELECT xmlpi(name xmlstuff, null);
+ xmlpi 
+-------
+ 
+(1 row)
+
+SELECT xmlpi(name "xml-stylesheet", 'href="mystyle.css" type="text/css"');
+                         xmlpi                         
+-------------------------------------------------------
+ <?xml-stylesheet href="mystyle.css" type="text/css"?>
+(1 row)
+
+SELECT xmlpi(name foo, '   bar');
+    xmlpi    
+-------------
+ <?foo bar?>
+(1 row)
+
+SELECT xmlroot(xml '<foo/>', version no value, standalone no value);
+ xmlroot 
+---------
+ <foo/>
+(1 row)
+
+SELECT xmlroot(xml '<foo/>', version '2.0');
+           xmlroot           
+-----------------------------
+ <?xml version="2.0"?><foo/>
+(1 row)
+
+SELECT xmlroot(xml '<foo/>', version no value, standalone yes);
+                   xmlroot                    
+----------------------------------------------
+ <?xml version="1.0" standalone="yes"?><foo/>
+(1 row)
+
+SELECT xmlroot(xml '<?xml version="1.1"?><foo/>', version no value, standalone yes);
+                   xmlroot                    
+----------------------------------------------
+ <?xml version="1.0" standalone="yes"?><foo/>
+(1 row)
+
+SELECT xmlroot(xmlroot(xml '<foo/>', version '1.0'), version '1.1', standalone no);
+                   xmlroot                   
+---------------------------------------------
+ <?xml version="1.1" standalone="no"?><foo/>
+(1 row)
+
+SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value, standalone no);
+                   xmlroot                   
+---------------------------------------------
+ <?xml version="1.0" standalone="no"?><foo/>
+(1 row)
+
+SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value, standalone no value);
+ xmlroot 
+---------
+ <foo/>
+(1 row)
+
+SELECT xmlroot('<?xml version="1.1" standalone="yes"?><foo/>', version no value);
+                   xmlroot                    
+----------------------------------------------
+ <?xml version="1.0" standalone="yes"?><foo/>
+(1 row)
+
+SELECT xmlroot (
+  xmlelement (
+    name gazonk,
+    xmlattributes (
+      'val' AS name,
+      1 + 1 AS num
+    ),
+    xmlelement (
+      NAME qux,
+      'foo'
+    )
+  ),
+  version '1.0',
+  standalone yes
+);
+                                         xmlroot                                          
+------------------------------------------------------------------------------------------
+ <?xml version="1.0" standalone="yes"?><gazonk name="val" num="2"><qux>foo</qux></gazonk>
+(1 row)
+
+SELECT xmlserialize(content data as character varying(20)) FROM xmltest;
+    xmlserialize    
+--------------------
+ <value>one</value>
+ <value>two</value>
+(2 rows)
+
+SELECT xmlserialize(content 'good' as char(10));
+ xmlserialize 
+--------------
+ good      
+(1 row)
+
+SELECT xmlserialize(document 'bad' as text);
+ERROR:  not an XML document
+SELECT xml '<foo>bar</foo>' IS DOCUMENT;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT xml '<foo>bar</foo><bar>foo</bar>' IS DOCUMENT;
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT xml '<abc/>' IS NOT DOCUMENT;
+ ?column? 
+----------
+ f
+(1 row)
+
+SELECT xml 'abc' IS NOT DOCUMENT;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '<>' IS NOT DOCUMENT;
+ERROR:  invalid XML content
+LINE 1: SELECT '<>' IS NOT DOCUMENT;
+               ^
+DETAIL:  Entity: line 1: parser error : StartTag: invalid element name
+<>
+ ^
+SELECT xmlagg(data) FROM xmltest;
+                xmlagg                
+--------------------------------------
+ <value>one</value><value>two</value>
+(1 row)
+
+SELECT xmlagg(data) FROM xmltest WHERE id > 10;
+ xmlagg 
+--------
+ 
+(1 row)
+
+SELECT xmlelement(name employees, xmlagg(xmlelement(name name, name))) FROM emp;
+                                                           xmlelement                                                           
+--------------------------------------------------------------------------------------------------------------------------------
+ <employees><name>sharon</name><name>sam</name><name>bill</name><name>jeff</name><name>cim</name><name>linda</name></employees>
+(1 row)
+
+-- Check mapping SQL identifier to XML name
+SELECT xmlpi(name ":::_xml_abc135.%-&_");
+                      xmlpi                      
+-------------------------------------------------
+ <?_x003A_::_x005F_xml_abc135._x0025_-_x0026__?>
+(1 row)
+
+SELECT xmlpi(name "123");
+     xmlpi     
+---------------
+ <?_x0031_23?>
+(1 row)
+
+PREPARE foo (xml) AS SELECT xmlconcat('<foo/>', $1);
+SET XML OPTION DOCUMENT;
+EXECUTE foo ('<bar/>');
+  xmlconcat   
+--------------
+ <foo/><bar/>
+(1 row)
+
+EXECUTE foo ('bad');
+ERROR:  invalid XML document
+LINE 1: EXECUTE foo ('bad');
+                     ^
+DETAIL:  Entity: line 1: parser error : Start tag expected, '<' not found
+bad
+^
+SET XML OPTION CONTENT;
+EXECUTE foo ('<bar/>');
+  xmlconcat   
+--------------
+ <foo/><bar/>
+(1 row)
+
+EXECUTE foo ('good');
+ xmlconcat  
+------------
+ <foo/>good
+(1 row)
+
+-- Test backwards parsing
+CREATE VIEW xmlview1 AS SELECT xmlcomment('test');
+CREATE VIEW xmlview2 AS SELECT xmlconcat('hello', 'you');
+CREATE VIEW xmlview3 AS SELECT xmlelement(name element, xmlattributes (1 as ":one:", 'deuce' as two), 'content&');
+CREATE VIEW xmlview4 AS SELECT xmlelement(name employee, xmlforest(name, age, salary as pay)) FROM emp;
+CREATE VIEW xmlview5 AS SELECT xmlparse(content '<abc>x</abc>');
+CREATE VIEW xmlview6 AS SELECT xmlpi(name foo, 'bar');
+CREATE VIEW xmlview7 AS SELECT xmlroot(xml '<foo/>', version no value, standalone yes);
+CREATE VIEW xmlview8 AS SELECT xmlserialize(content 'good' as char(10));
+CREATE VIEW xmlview9 AS SELECT xmlserialize(content 'good' as text);
+SELECT table_name, view_definition FROM information_schema.views
+  WHERE table_name LIKE 'xmlview%' ORDER BY 1;
+ table_name |                                                      view_definition                                                       
+------------+----------------------------------------------------------------------------------------------------------------------------
+ xmlview1   | SELECT xmlcomment('test'::text) AS xmlcomment;
+ xmlview2   | SELECT XMLCONCAT('hello'::xml, 'you'::xml) AS "xmlconcat";
+ xmlview3   | SELECT XMLELEMENT(NAME element, XMLATTRIBUTES(1 AS ":one:", 'deuce' AS two), 'content&') AS "xmlelement";
+ xmlview4   | SELECT XMLELEMENT(NAME employee, XMLFOREST(emp.name AS name, emp.age AS age, emp.salary AS pay)) AS "xmlelement" FROM emp;
+ xmlview5   | SELECT XMLPARSE(CONTENT '<abc>x</abc>'::text STRIP WHITESPACE) AS "xmlparse";
+ xmlview6   | SELECT XMLPI(NAME foo, 'bar'::text) AS "xmlpi";
+ xmlview7   | SELECT XMLROOT('<foo/>'::xml, VERSION NO VALUE, STANDALONE YES) AS "xmlroot";
+ xmlview8   | SELECT (XMLSERIALIZE(CONTENT 'good'::xml AS character(10)))::character(10) AS "xmlserialize";
+ xmlview9   | SELECT XMLSERIALIZE(CONTENT 'good'::xml AS text) AS "xmlserialize";
+(9 rows)
+
+-- Text XPath expressions evaluation
+SELECT xpath('/value', data) FROM xmltest;
+        xpath         
+----------------------
+ {<value>one</value>}
+ {<value>two</value>}
+(2 rows)
+
+SELECT xpath(NULL, NULL) IS NULL FROM xmltest;
+ ?column? 
+----------
+ t
+ t
+(2 rows)
+
+SELECT xpath('', '<!-- error -->');
+ERROR:  empty XPath expression
+CONTEXT:  SQL function "xpath" statement 1
+SELECT xpath('//text()', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>');
+     xpath      
+----------------
+ {"number one"}
+(1 row)
+
+SELECT xpath('//loc:piece/@id', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+ xpath 
+-------
+ {1,2}
+(1 row)
+
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+                                                                     xpath                                                                      
+------------------------------------------------------------------------------------------------------------------------------------------------
+ {"<local:piece xmlns:local=\"http://127.0.0.1\" id=\"1\">number one</local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
+(1 row)
+
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1" xmlns="http://127.0.0.2"><local:piece id="1"><internal>number one</internal><internal2/></local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+                                        xpath                                         
+--------------------------------------------------------------------------------------
+ {"<local:piece xmlns:local=\"http://127.0.0.1\" xmlns=\"http://127.0.0.2\" id=\"1\">+
+   <internal>number one</internal>                                                   +
+   <internal2/>                                                                      +
+ </local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
+(1 row)
+
+SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>');
+          xpath          
+-------------------------
+ {<b>two</b>,<b>etc</b>}
+(1 row)
+
+-- Test xmlexists and xpath_exists
+SELECT xmlexists('//town[text() = ''Toronto'']' PASSING BY REF '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>');
+ xmlexists 
+-----------
+ f
+(1 row)
+
+SELECT xmlexists('//town[text() = ''Cwmbran'']' PASSING BY REF '<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>');
+ xmlexists 
+-----------
+ t
+(1 row)
+
+SELECT xpath_exists('//town[text() = ''Toronto'']','<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>'::xml);
+ xpath_exists 
+--------------
+ f
+(1 row)
+
+SELECT xpath_exists('//town[text() = ''Cwmbran'']','<towns><town>Bidford-on-Avon</town><town>Cwmbran</town><town>Bristol</town></towns>'::xml);
+ xpath_exists 
+--------------
+ t
+(1 row)
+
+INSERT INTO xmltest VALUES (4, '<menu><beers><name>Budvar</name><cost>free</cost><name>Carling</name><cost>lots</cost></beers></menu>'::xml);
+INSERT INTO xmltest VALUES (5, '<menu><beers><name>Molson</name><cost>free</cost><name>Carling</name><cost>lots</cost></beers></menu>'::xml);
+INSERT INTO xmltest VALUES (6, '<myns:menu xmlns:myns="http://myns.com"><myns:beers><myns:name>Budvar</myns:name><myns:cost>free</myns:cost><myns:name>Carling</myns:name><myns:cost>lots</myns:cost></myns:beers></myns:menu>'::xml);
+INSERT INTO xmltest VALUES (7, '<myns:menu xmlns:myns="http://myns.com"><myns:beers><myns:name>Molson</myns:name><myns:cost>free</myns:cost><myns:name>Carling</myns:name><myns:cost>lots</myns:cost></myns:beers></myns:menu>'::xml);
+SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beer' PASSING data);
+ count 
+-------
+     0
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beer' PASSING BY REF data BY REF);
+ count 
+-------
+     0
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beers' PASSING BY REF data);
+ count 
+-------
+     2
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xmlexists('/menu/beers/name[text() = ''Molson'']' PASSING BY REF data);
+ count 
+-------
+     1
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beer',data);
+ count 
+-------
+     0
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beers',data);
+ count 
+-------
+     2
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/menu/beers/name[text() = ''Molson'']',data);
+ count 
+-------
+     1
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beer',data,ARRAY[ARRAY['myns','http://myns.com']]);
+ count 
+-------
+     0
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beers',data,ARRAY[ARRAY['myns','http://myns.com']]);
+ count 
+-------
+     2
+(1 row)
+
+SELECT COUNT(id) FROM xmltest WHERE xpath_exists('/myns:menu/myns:beers/myns:name[text() = ''Molson'']',data,ARRAY[ARRAY['myns','http://myns.com']]);
+ count 
+-------
+     1
+(1 row)
+
+CREATE TABLE query ( expr TEXT );
+INSERT INTO query VALUES ('/menu/beers/cost[text() = ''lots'']');
+SELECT COUNT(id) FROM xmltest, query WHERE xmlexists(expr PASSING BY REF data);
+ count 
+-------
+     2
+(1 row)
+
+-- Test xml_is_well_formed and variants
+SELECT xml_is_well_formed_document('<foo>bar</foo>');
+ xml_is_well_formed_document 
+-----------------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed_document('abc');
+ xml_is_well_formed_document 
+-----------------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed_content('<foo>bar</foo>');
+ xml_is_well_formed_content 
+----------------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed_content('abc');
+ xml_is_well_formed_content 
+----------------------------
+ t
+(1 row)
+
+SET xmloption TO DOCUMENT;
+SELECT xml_is_well_formed('abc');
+ xml_is_well_formed 
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<>');
+ xml_is_well_formed 
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<abc/>');
+ xml_is_well_formed 
+--------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed('<foo>bar</foo>');
+ xml_is_well_formed 
+--------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed('<foo>bar</foo');
+ xml_is_well_formed 
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<foo><bar>baz</foo>');
+ xml_is_well_formed 
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>');
+ xml_is_well_formed 
+--------------------
+ t
+(1 row)
+
+SELECT xml_is_well_formed('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</my:foo>');
+ xml_is_well_formed 
+--------------------
+ f
+(1 row)
+
+SELECT xml_is_well_formed('<pg:foo xmlns:pg="http://postgresql.org/stuff">bar</pg:foo>');
+ xml_is_well_formed 
+--------------------
+ t
+(1 row)
+
+SET xmloption TO CONTENT;
+SELECT xml_is_well_formed('abc');
+ xml_is_well_formed 
+--------------------
+ t
+(1 row)
+
+-- External entity references should not leak filesystem information.
+SELECT XMLPARSE(DOCUMENT '<!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/passwd">]><foo>&c;</foo>');
+                            xmlparse                             
+-----------------------------------------------------------------
+ <!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/passwd">]><foo>&c;</foo>
+(1 row)
+
+SELECT XMLPARSE(DOCUMENT '<!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/no.such.file">]><foo>&c;</foo>');
+                               xmlparse                                
+-----------------------------------------------------------------------
+ <!DOCTYPE foo [<!ENTITY c SYSTEM "/etc/no.such.file">]><foo>&c;</foo>
+(1 row)
+
+-- This might or might not load the requested DTD, but it mustn't throw error.
+SELECT XMLPARSE(DOCUMENT '<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"><chapter>&nbsp;</chapter>');
+                                                                       xmlparse                                                                       
+------------------------------------------------------------------------------------------------------------------------------------------------------
+ <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd"><chapter>&nbsp;</chapter>
+(1 row)
+