struct tree_type

[BLUE 3TOO]

Hello,
 
    I did a quick search on "gcc internal" document and cannot find any explanation about the field meaning of struct tree_type. I am trying to use typedef to introduce some new aggregrate types that my gcc can handle. And I want to mark these  types so that I can handle these types specifically.  I might have to differenciate my own types into several categories, therefore I need several marking bits. My application will be in C/C++. Is there any fields that I can recycle? Or it is better to introduce some new fields. 
 
 
     Can somebody quickly explain what the bit fields are for? thanks
 
  unsigned int precision : 10;
  unsigned no_force_blk_flag : 1;
  unsigned needs_constructing_flag : 1;
  unsigned transparent_aggr_flag : 1;
  unsigned restrict_flag : 1;
  unsigned contains_placeholder_bits : 2;
  ENUM_BITFIELD(machine_mode) mode : 8;
  unsigned string_flag : 1;
  unsigned lang_flag_0 : 1;
  unsigned lang_flag_1 : 1;
  unsigned lang_flag_2 : 1;
  unsigned lang_flag_3 : 1;
  unsigned lang_flag_4 : 1;
  unsigned lang_flag_5 : 1;
  unsigned lang_flag_6 : 1; 		 	   		  
_________________________________________________________________
Game on: Challenge friends to great games on Messenger
http://go.microsoft.com/?linkid=9734387