Installation
The XMLReader extension is available in PECL as of PHP 5.0.0 and is included and enabled as of PHP 5.1.0 by default. It can be enabled by adding the argument --enable-xmlreader (or --with-xmlreader before 5.1.0) to the configure line.
This extension is enabled by default. It may be disabled by using the following option at compile time: --disable-xmlreader