error when wordpress is installed in separate directory then started in site root from function

[helened]

When wordpress is installed in it's own directory and is started within a function in "index.php" in site root, these errors occur:

This fatal error occurs in WP 3.8.1:
[08-Apr-2014 19:34:50 UTC] PHP Fatal error: Call to a member function main() on a non-object in .../mywordpress/wp-includes/functions.php on line 808

In WP 3.9-beta3, the error changes to this non-fatal error:
[08-Apr-2014 19:53:51 UTC] PHP Warning: in_array() expects parameter 2 to be array, null given in .../mywordpress/wp-includes/kses.php on line 1176

Code samples:
index.php (no error):

   <?php require("mywordpress/index.php");?>

index.php (error):

<?php
    function site_startup(){
	     require("mywordpress/index.php");
    }
    site_startup();
    exit;
?>

Tested with PHP 5.4 on Windows (PC XAMPP server) and Linux (Bluehost.com server).

[jesin]

Hi Helened,

Why are you trying to include this file inside the function? Doing this will make WordPress execute like this -

function site_startup() {
    //Entire WordPress code
}

That means the entire scope of WordPress will come into this function.

From the discussion on PHP's require() documentation page - ​http://www.php.net/manual/en/function.require.php#87191

require executes the code "as if" it was code written inside of the function, inheriting everything including the scope.

[SergeyBiryukov]

Related: #23685 (comment:5:ticket:23685), #26867.