PHP_VERSION_ID is int but not defined. (PHP-FPM 5.4.4)
<p>Title explains it but here's what I tried to do:</p>

<pre><code>if (!defined(PHP_VERSION_ID) || PHP_VERSION_ID &lt; 50400) {
    trigger_error('PHP version 5.4 or above is required to run this code. Please upgrade to continue...', E_USER_ERROR);
}
</code></pre>

<p>For some reason this is what's going on:</p>

<pre><code>var_dump(PHP_VERSION_ID);          // returns int(50404)
var_dump(defined(PHP_VERSION_ID)); // returns bool(false)
</code></pre>

<p>According to php.net page on <code>defined</code> you can do this:</p>

<pre><code>&lt;?php
// PHP_VERSION_ID is available as of PHP 5.2.7, if our 
// version is lower than that, then emulate it
if (!defined('PHP_VERSION_ID')) {
    $version = explode('.', PHP_VERSION);

    define('PHP_VERSION_ID', ($version[0] * 10000 + $version[1] * 100 + $version[2]));
}

// PHP_VERSION_ID is defined as a number, where the higher the number 
// is, the newer a PHP version is used. It's defined as used in the above 
// expression:
//
// $version_id = $major_version * 10000 + $minor_version * 100 + $release_version;
//
// Now with PHP_VERSION_ID we can check for features this PHP version 
// may have, this doesn't require to use version_compare() everytime 
// you check if the current PHP version may not support a feature.
//
// For example, we may here define the PHP_VERSION_* constants thats 
// not available in versions prior to 5.2.7

if (PHP_VERSION_ID &lt; 50207) {
    define('PHP_MAJOR_VERSION',   $version[0]);
    define('PHP_MINOR_VERSION',   $version[1]);
    define('PHP_RELEASE_VERSION', $version[2]);

    // and so on, ...
}
?&gt;
</code></pre>

<p>Any ideas on why this isn't working? I'm running PHP-FPM 5.4.4 on Debian Wheezy.</p>
