How to recover from a borked cache?
For me the following hack worked:


Edit includes/cache.inc. Let function cache_get() return FALSE.
Run drush cc all.
Revert the hack in includes/cache.inc.


I am not saying this is the best solution. But it did work for me, on a dev system. I am not sure I would recommend this on a production system.

Here is the hack:

 function cache_get($cid, $bin = 'cache') {
+  return FALSE;
+  # return _cache_get_object($bin)-&gt;get($cid);
-  return _cache_get_object($bin)-&gt;get($cid);
 }