Getting WSOD on all Admin pages

Question

Like the title says, I'm getting the WSOD (white screen of death) when going to any admin page. This just started happening when I arrived this Monday, Friday it was working fine.

Here's what I've tried

1. Checking php settings:

   memory_limit    5000M   128M
   max_execution_time  600000000   600000000
   output_buffering    On  4096
   output_handler  mb_output_handler   no value
   Connection: 300 - Keep-Alive: 15
   default_socket_timeout  60
   memcache.default_timeout_ms 1000    1000
   mysql.connect_timeout 60 60
   

2. Added error reporting to index.php

   error_reporting(E_ALL);
   ini_set('display_errors', TRUE);
   ini_set('display_startup_errors', TRUE);
   

3. Check drupal watchdog and apache logs

   No errors

4. Check disk space on web server and database server

   Plenty of space

5. Ran command to find any PHP errors

   find /data/ -type f -name "*.php" -exec php -l {} \; | grep -v 'No syntax errors'
   find /data/ -type f -name "*.inc" -exec php -l {} \; | grep -v 'No syntax errors'
   find /data/ -type f -name "*.module" -exec php -l {} \; | grep -v 'No syntax errors'
   

   Errors: None

6. Clear cache table

   TRUNCATE TABLE cache; (anything that started with cache)
   

7. Restarted web server

8. Disabled all themes, only enabled garland theme and set it to default

   update `system` set status = 0 where type = 'theme'
   UPDATE system SET status=1 WHERE name = 'garland';
   UPDATE variable SET value='s:7:"garland"' WHERE name = 'theme_default';
   Truncate cache tables
   

9. Disabled all modules and re-enabled them 1 at a time. I started with user module, it displayed errors on the screen regarding system module. I enabled system module and then I got WSOD again.

UPDATE: I set the admin_theme variable to garland. Then the page work. When I went to admin/build/themes and enabled marvin, I got the WSOD. Even re-disabling marvin and clearing the cache tables, I still get the WSOD.

Answer 1

The issue that was causing it for me was that I had _theme function with no code inside.

function tf_cart_theme()
{
  //
}