hash.c:28
static void
rb_hash_modify(hash)
    VALUE hash;
{
    if (!RHASH(hash)->tbl) rb_raise(rb_eTypeError, "uninitialized Hash");
    if (OBJ_FROZEN(hash)) rb_error_frozen("hash");
    if (!OBJ_TAINTED(hash) && rb_safe_level() >= 4)
	rb_raise(rb_eSecurityError, "Insecure: can't modify hash");
}
