BTW, I’m using wordpress 3.0.1. I’m totally stuck. I’ve found some discussions online regarding this error message but they’re way to technical for me to even begin to understand. If there’s a solution can somebody please walk me through it?
Hi!
I have also updated WordPress to latest 3.0.1. by using auto update. And got the same problem.
Did You fixed it?
What I did – just commented /wp-includes/query.php line 419: set
`return $wp_query->is_page( $page );`
to
`//return $wp_query->is_page( $page );`
at least, page works for now.
To fix the error message, at-least for now, delete the buddypress plugin, then re-install it. Sometimes updates can screw up plugins. (especially a major plugin like buddypress)
In the future, deactivate such plugins to avoid this.
I am also facing the same problem.
geting this error -> Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 30720 bytes) in /home/*/public_html*/*/wp-content/themes/*/includes/theme-post-types.php on line 28
I can’t even able to open my site. 
and how to delete this F**kin Plugin. please tell me. i cant even login to my admin. i hv 3.0.2.
@avinanrey just log onto your server via FTP, and rename the BuddyPress plugin directory, or delete it. This works for any malfunctioning plugin. It will be immediately disabled.
I have come across the same error with WP 3.1 beta 1. Apparently WordPress normally ignores this error.
Fatal error: Call to a member function is_page() on a non-object in /public_html/wp-includes/query.php on line 419
But the issue lies with the plugin.
https://wordpress.org/news/2010/11/wordpress-3-1-beta-1/
So BuddyPress needs to fixed.
We’re aware of the is_page() issue with WP 3.1
@avinanrey keep your language polite.
Is there a fix for this?
I can’t install without getting this error.
