Can you confirm you’re testing on WP 4.0-beta, and using a default theme? If not, please test again on the default theme (TwentyFourteen).
Also make sure your install of the beta was complete.
Edit: This is likely the same issue:
Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, ‘WP_Comments_List_Table::_js_vars’ was given in C:\wamp\www\wordpress\wp-includes\plugin.php on line 488
with WAMP Apache 2.2.6 PHP 5.2.5
Merging your posts to make it a little easier on us 🙂
It’s on 4.0 beta1, with my child-theme.
But with Twenty fourteen, same error.
There is a problem with the file : wp-includes is missing on download.
I use french version “fr_FR”
Now, i have all the files of the french version and it’s the same error.
Wait, what file is missing on download?
Previously, the entire file wp-includes missing.
Now, this entire file is present, but the error, it is still there.
Okay, can you delete the wp-includes folder and wp-admin, and then manually download and install beta? I think you have a bad download and it’s not fixing itself.
I manually downloaded the archive:
https://wordpress.org/wordpress-4.0-beta1.zip
found on this page of wordpree-fr.net :
http://www.wordpress-fr.net/2014/07/11/wordpress-4-0-beta-1-est-disponible/
It’s still the same error on apache 2.2.6 PHP 5.2.5
I trying another version of PHP.
On a new install with easyPHP 14.1
PHP Version : 5.4.24 / 32Bit OS
There is no error.
But For an update on WAMP with PHP 5.2.5 from WordPress 3.9.1, there is an error.
On a new install on WAMP server 2.0 with PHP 5.2.5 there is the error :
Warning: Wrong parameter count for array_unique() in C:\wamp\www\wordpress4\wp-includes\taxonomy.php on line 2348
The reason I asked is that you said the wp-includes folder (not file, it’s a folder, it should have a ton of files inside 🙂 ) was missing, so that implies you had a bad install.
Okay, so this looks like a PHP 5.2.5 issue which would explain why I can’t see it.
Sorry for my English, it is Google that translates.
Totally alright!
Created https://core.trac.wordpress.org/ticket/28843 for tracking
I’m marking this post as resolved since we have a trac ticket. You can follow the ticket if you want.
