fixed:

==2761== Thread 10:
==2761== Conditional jump or move depends on uninitialised value(s)
==2761==    at 0x818F580: make_join_statistics(JOIN*, st_table_list*, Item*, st_dynamic_array*) (sql_select.cc:1850)
==2761==    by 0x818B705: JOIN::optimize() (sql_select.cc:578)


sql/sql_select.cc:
  optimize field should be initialized in case of fulltext index

sql/sql_select.cc

@@ -2407,6 +2407,7 @@ add_ft_keys(DYNAMIC_ARRAY *keyuse_array,
   keyuse.key =  cond_func->key;
   keyuse.keypart= FT_KEYPART;
   keyuse.used_tables=cond_func->key_item()->used_tables();
+  keyuse.optimize= 0;
   VOID(insert_dynamic(keyuse_array,(gptr) &keyuse));
 }