variable.c:1607
VALUE
rb_cvar_get(klass, id)
    VALUE klass;
    ID id;
{
    VALUE value;
    VALUE tmp;

    tmp = klass;
    while (tmp) {
	if (RCLASS(tmp)->iv_tbl) {
	    if (st_lookup(RCLASS(tmp)->iv_tbl,id,&value)) {
		if (RTEST(ruby_verbose)) {
		    cvar_override_check(id, tmp);
		}
		return value;
	    }
	}
	tmp = RCLASS(tmp)->super;
    }

    rb_name_error(id,"uninitialized class variable %s in %s",
		  rb_id2name(id), rb_class2name(klass));
    return Qnil;		/* not reached */
}
