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visit http://www.php.net/support.php as this bug system is not the
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Thank you for your interest in PHP.

Known limitation of libxml2

The function DOMNode::getLineNo() is not able to return a line number higher 
than 65535.

Test Script:

<?php
$xml = "<?xml version=\"1.0\"?><root>".str_repeat("\n", 65537)
       ."<mix>end</mix>\n<mix>end</mix></root>"
       ;
echo dom_import_simplexml(
         end(simplexml_load_string($xml)->xpath('//text()'))
     )->getLineNo()
     ;
?>

Expected result: 65537

Actual result: 65535

Summary: Reported back in 2007, upstream does not know how to fix this w/o 
breaking stuff (binary compatibility). 
It's also worth to mention that normally files with more than 65k lines aren't 
written by hand so don't require that 
type of functionality. Naturally this is subjective.

To fix this this requires a different upstream/patch of one of the underlying 
libraries, e.g. libxml2. The debian 
ticket has a patch.

https://mail.gnome.org/archives/xml/2007-October/msg00002.html

http://lxr.php.net/xref/PHP_5_3/ext/dom/node.c#1955

http://lxr.php.net/xref/PHP_5_3/ext/libxml/php_libxml2.def#419

http://xmlsoft.org/html/libxml-tree.html#xmlGetLineNo

https://bugzilla.gnome.org/show_bug.cgi?id=676026

http://stackoverflow.com/a/11099693/367456

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=445961

This is solved in libxml2 version 2.9+.
However, you have to explicitly tell libxml to support it, which you can do in PHP by using using the options parameter in functions like DOMDocument::load (option 2^22 = 4194304 = XML_PARSE_BIG_LINES). Currently there's no PHP libxml constant for that purpose.

Re-opened according to Ruud's comment. Not sure, whether that should be categorized as feature request, though.

Thanks for the hint, Ruud. Indeed, as of libxml2 2.9.0 there is
the constant XML_PARSE_BIG_LINES available:
<https://git.gnome.org/browse/libxml2/commit/include/libxml/parser.h?id=968a03a2e54f5bcf53089f5e3c8f790dbe0bf824>.

I'll make a PR to add a respective constant to PHP, so users don't
have to rely on a hard to remember and potentially changing
numeric value.

The fix for this bug has been committed.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.

 For Windows:

http://windows.php.net/snapshots/
 
Thank you for the report, and for helping us make PHP better.