Typedefs:

declNode makes some typedefs:

•  typedef enum {                                                                
      UNKNOWN, TOP, BLOCK, FORMAL, SU, ENUM, PROC                                 
   } Decl_location;
  

  This enumerated type names the possible locations of the declaration. This information is needed for, among other things, deciding how to format the declaration for output to a .c file. For example, a declaration in a function prototype is followed by a comma, but a declaration in the global scope is followed by a semicolon.

•  typedef enum {                                                                
      NONE, AUTO, EXTERN, REGISTER, STATIC, TYPEDEF                               
   } Storage_class;
  

  This enumerated type names the C storage classes. Note that a typedef is just a variable declaration with storage class TYPEDEF.