* cpphash.h (struct _cpp_buff, _cpp_get_buff, _cpp_release_buff,
	_cpp_extend_buff, _cpp_free_buff): New.
	(struct cpp_reader): New member free_buffs.
	* cppinit.c (cpp_destroy): Free buffers.
	* cpplex.c (new_buff, _cpp_release_buff, _cpp_get_buff,
	_cpp_extend_buff, _cpp_free_buff): New.
	* cpplib.h (struct cpp_options): Remove unused member.
	* cppmacro.c (collect_args): New.  Combines the old parse_arg
	and parse_args.  Use _cpp_buff for memory allocation.
	(funlike_invocation_p, replace_args): Update.

From-SVN: r45827