=== modified file 'storage/myisam/mi_check.c'
--- storage/myisam/mi_check.c	2013-02-27 15:33:55 +0000
+++ storage/myisam/mi_check.c	2013-06-23 13:54:44 +0000
@@ -4703,10 +4703,13 @@
   */
   if (! mi_is_any_key_active(key_map))
     return FALSE;				/* Can't use sort */
-  for (i=0 ; i < share->base.keys ; i++,key++)
+  if (!force)
   {
-    if (!force && mi_too_big_key_for_sort(key,rows))
-      return FALSE;
+    for (i=0 ; i < share->base.keys ; i++,key++)
+    {
+      if (mi_too_big_key_for_sort(key,rows))
+        return FALSE;
+    }
   }
   return TRUE;
 }