1 files changed, 14 insertions, 10 deletions

diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index d950c0c1443..3e64e3969e4 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -1,5 +1,5 @@
 /* Copyright (c) 2000, 2012, Oracle and/or its affiliates.
-   Copyright (c) 2009, 2012 Monty Program Ab
+   Copyright (c) 2009, 2013, Monty Program Ab.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -914,7 +914,7 @@ get_datetime_value(THD *thd, Item ***item_arg, Item **cache_arg,
     if (save_arena)
       thd->set_query_arena(save_arena);
 
-    cache->store_packed(value);
+    cache->store_packed(value, item);
     *cache_arg= cache;
     *item_arg= cache_arg;
   }
@@ -1353,7 +1353,7 @@ int Arg_comparator::compare_e_row()
 
 void Item_func_truth::fix_length_and_dec()
 {
-  maybe_null= 0;
+  set_persist_maybe_null(0);
   null_value= 0;
   decimals= 0;
   max_length= 1;
@@ -1865,7 +1865,8 @@ longlong Item_func_eq::val_int()
 void Item_func_equal::fix_length_and_dec()
 {
   Item_bool_func2::fix_length_and_dec();
-  maybe_null=null_value=0;
+  set_persist_maybe_null(0);
+  null_value= 0;
 }
 
 longlong Item_func_equal::val_int()
@@ -2004,7 +2005,7 @@ void Item_func_interval::fix_length_and_dec()
       }
     }
   }
-  maybe_null= 0;
+  set_persist_maybe_null(0);
   max_length= 2;
   used_tables_cache|= row->used_tables();
   not_null_tables_cache= row->not_null_tables();
@@ -2685,7 +2686,7 @@ void
 Item_func_nullif::fix_length_and_dec()
 {
   Item_bool_func2::fix_length_and_dec();
-  maybe_null=1;
+  set_persist_maybe_null(1);
   if (args[0])					// Only false if EOM
   {
     max_length=args[0]->max_length;
@@ -4546,6 +4547,8 @@ void Item_cond::update_used_tables()
     item->update_used_tables();
     used_tables_cache|= item->used_tables();
     const_item_cache&= item->const_item();
+    if (!persistent_maybe_null && item->maybe_null)
+      maybe_null= 1;
   }
 }
 
@@ -4720,10 +4723,9 @@ longlong Item_is_not_null_test::val_int()
 */
 void Item_is_not_null_test::update_used_tables()
 {
+  args[0]->update_used_tables();
   if (!args[0]->maybe_null)
     used_tables_cache= 0;			/* is always true */
-  else
-    args[0]->update_used_tables();
 }
 
 
@@ -5004,7 +5006,7 @@ Item_func_regex::fix_fields(THD *thd, Item **ref)
     int comp_res= regcomp(TRUE);
     if (comp_res == -1)
     {						// Will always return NULL
-      maybe_null=1;
+      set_persist_maybe_null(1);
       fixed= 1;
       return FALSE;
     }
@@ -5014,7 +5016,7 @@ Item_func_regex::fix_fields(THD *thd, Item **ref)
     maybe_null= args[0]->maybe_null;
   }
   else
-    maybe_null=1;
+    set_persist_maybe_null(1);
   fixed= 1;
   return FALSE;
 }
@@ -5828,6 +5830,8 @@ void Item_equal::update_used_tables()
     used_tables_cache|= item->used_tables();
     /* see commentary at Item_equal::update_const() */
     const_item_cache&= item->const_item() && !item->is_outer_field();
+    if (!persistent_maybe_null && item->maybe_null)
+      maybe_null= 1;
   }
 }