PHP Warning from function.php

Hi,

I’ve been receiving an error via the hosting log file that states:

PHP Warning: array_push() expects parameter 1 to be array, null given in /home/sites/codecmoments.com/public_html/wp-content/themes/gamepress/functions.php on line 13

This appears to be this section of code in the theme:

// Set the content width
if ( ! isset( $content_width ) )
$content_width = 598; /* pixels */

function myfeed_request($qv) {
if (isset($qv[‘feed’]) && !isset($qv[‘post_type’]))
$qv[‘post_type’] = get_post_types($args = array(
‘public’ => true,
‘_builtin’ => false
));
array_push($qv[‘post_type’],’post’);
return $qv;
}
add_filter(‘request’, ‘myfeed_request’);

Specifically line 13:

array_push($qv[‘post_type’],’post’);

Any ideas on why this would generate an error? The hosting is suggesting this might be contributing to a recent 500 Internal Server error, though after 18 months of use it’s the first time it’s cropped up.

Thanks for any advice/help you can give.