Description:
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When the ZE1 compatibility has been enabled (in php.ini: zend.ze1_compatibility_mode=On), the usage of domXpath::query() results in an Invalid XPath Context error.

There are no problems when the ZE1 compatibility is disabled.



Reproduce code:
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$dom = new domDocument;
$dom->loadXML("<root> hello </root>");
$xpath = new domXPath($dom);
$results = $xpath->query('//root');

echo "<b>Node value:</b> ", $results->item(0)->nodeValue;

Expected result:
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Node value: hello

Actual result:
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Warning: Invalid XPath Context in [...] on line [...]