Member no_rotate in MYSQL_LOG was always 0, I delete it.

sql/log.cc

@@ -83,7 +83,7 @@ static int find_uniq_filename(char *name)
 MYSQL_LOG::MYSQL_LOG()
   :bytes_written(0), last_time(0), query_start(0), name(0),
    file_id(1), open_count(1), log_type(LOG_CLOSED), write_error(0),
-   no_rotate(0), need_start_event(1)
+   need_start_event(1)
 {
   /*
     We don't want to initialize LOCK_Log here as such initialization depends on
@@ -721,7 +721,6 @@ err:
 
   RETURN VALUES
     0				ok
-    LOG_INFO_PURGE_NO_ROTATE	Binary file that can't be rotated
     LOG_INFO_EOF		to_log not found
 */
 
@@ -731,9 +730,6 @@ int MYSQL_LOG::purge_logs(THD* thd, const char* to_log)
   LOG_INFO log_info;
   DBUG_ENTER("purge_logs");
 
-  if (no_rotate)
-    DBUG_RETURN(LOG_INFO_PURGE_NO_ROTATE);
-
   pthread_mutex_lock(&LOCK_index);
   if ((error=find_log_pos(&log_info, to_log, 0 /*no mutex*/)))
     goto err;
@@ -839,12 +835,6 @@ void MYSQL_LOG::new_file(bool need_lock)
   // Reuse old name if not binlog and not update log
   new_name_ptr= name;
 
-  /*
-    Only rotate open logs that are marked non-rotatable
-    (binlog with constant name are non-rotatable)
-  */
-  if (!no_rotate)
-  {
   /*
     If user hasn't specified an extension, generate a new log name
     We have to do this here and not in open as we want to store the
@@ -883,7 +873,6 @@ void MYSQL_LOG::new_file(bool need_lock)
     */
     signal_update(); 
   }
-  }
   old_name=name;
   save_log_type=log_type;
   name=0;				// Don't free name

sql/sql_class.h

@@ -39,7 +39,6 @@ enum enum_delay_key_write { DELAY_KEY_WRITE_NONE, DELAY_KEY_WRITE_ON,
 #define LOG_INFO_IO  -2
 #define LOG_INFO_INVALID -3
 #define LOG_INFO_SEEK -4
-#define LOG_INFO_PURGE_NO_ROTATE -5
 #define LOG_INFO_MEM -6
 #define LOG_INFO_FATAL -7
 #define LOG_INFO_IN_USE -8
@@ -86,7 +85,6 @@ class MYSQL_LOG {
   volatile enum_log_type log_type;
   enum cache_type io_cache_type;
   bool write_error;
-  bool no_rotate;
   bool need_start_event;
   bool no_auto_events; // for relay binlog
   /*