Description:
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When entity loading is disabled using libxml_disable_entity_loader(), XMLReader refuses to load XML data using its open() method.


Test script:
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<?php

libxml_disable_entity_loader();

$reader = new XMLReader();
$reader->open('php://stdin');


Expected result:
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The URL provided to open() is successfully opened.

Actual result:
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A warning is generated and the URL is not opened.