* process.c (socket_options): Make it const.
(set_socket_option, init_process): Use a const pointer.
* lread.c (intern_c_string): New function.
(defvar_kboard, defvar_lisp, defvar_lisp_nopro, defvar_bool)
(defvar_int): Uset it. Make the name const char*.
* lisp.h (defvar_kboard, defvar_lisp, defvar_lisp_nopro, defvar_bool)
(defvar_int): Update prototypes.
(DEFUN, EXFUN): Support for prototypes is now required.
(intern_c_string): New prototype.
(struct Lisp_Subr): Make symbol_name constant.
* font.c (struct table_entry): Remove unused member. Make NAMES
constant.
(weight_table, slant_table, width_table): Make constant.
* emacs.c (struct standard_args): Make name and longname constant.