diff --git a/libmysqld/lib_sql.cc b/libmysqld/lib_sql.cc
index fdc1acea09b..9fba0327525 100644
--- a/libmysqld/lib_sql.cc
+++ b/libmysqld/lib_sql.cc
@@ -591,7 +591,7 @@ err:
 
 C_MODE_END
 
-bool Protocol::send_fields(List<Item> *list, int flags)
+bool Protocol::send_fields(List<Item> *list, uint flags)
 {
   List_iterator_fast<Item> it(*list);
   Item                     *item;
diff --git a/sql/handler.cc b/sql/handler.cc
index 97708fa77fe..bb5e980f7bf 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -157,12 +157,11 @@ enum db_type ha_checktype(enum db_type database_type)
     break;
   }
   
-  return 
-    DB_TYPE_UNKNOWN != (enum db_type) thd->variables.table_type ?
-    (enum db_type) thd->variables.table_type :
-    DB_TYPE_UNKNOWN != (enum db_type) global_system_variables.table_type ?
-    (enum db_type) global_system_variables.table_type :
-    DB_TYPE_MYISAM;
+  return ((enum db_type) thd->variables.table_type != DB_TYPE_UNKNOWN ?
+          (enum db_type) thd->variables.table_type :
+          (enum db_type) global_system_variables.table_type !=
+          DB_TYPE_UNKNOWN ?
+          (enum db_type) global_system_variables.table_type : DB_TYPE_MYISAM);
 } /* ha_checktype */
 
 
@@ -784,10 +783,14 @@ bool ha_flush_logs()
 
 int ha_delete_table(enum db_type table_type, const char *path)
 {
+  handler *file;
   char tmp_path[FN_REFLEN];
-  handler *file=(table_type== DB_TYPE_UNKNOWN ? 0 : get_new_handler((TABLE*) 0, table_type));
-  if (!file)
+
+  /* DB_TYPE_UNKNOWN is used in ALTER TABLE when renaming only .frm files */
+  if (table_type == DB_TYPE_UNKNOWN ||
+      ! (file=get_new_handler((TABLE*) 0, table_type)))
     return ENOENT;
+
   if (lower_case_table_names == 2 && !(file->table_flags() & HA_FILE_BASED))
   {
     /* Ensure that table handler get path in lower case */
diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index e5d060f99fb..26c483a61a8 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -3085,7 +3085,6 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   }
 
   /* We don't want update TIMESTAMP fields during ALTER TABLE. */
-  new_table->timestamp_field_type= TIMESTAMP_NO_AUTO_SET;
   thd->count_cuted_fields= CHECK_FIELD_WARN;	// calc cuted fields
   thd->cuted_fields=0L;
   thd->proc_info="copy to tmp table";
@@ -3093,7 +3092,7 @@ int mysql_alter_table(THD *thd,char *new_db, char *new_name,
   copied=deleted=0;
   if (new_table && !new_table->is_view)
   {
-    new_table->timestamp_default_now= 0;
+    new_table->timestamp_field_type= TIMESTAMP_NO_AUTO_SET;
     new_table->next_number_field=new_table->found_next_number_field;
     error=copy_data_between_tables(table,new_table,create_list,
 				   handle_duplicates,