A few files had just <? which only works when the short_open_tag option
is on. It is on by default (at least in current PHP versions) and we
explicitly tell PHP not to read php.ini, but the PHP docs recommended to
avoid it, and PHP can be built with --disable-short-tags.
This function doesn't do anything currently so these missing calls are a
latent issue. It could be used for e.g. memory leak checking in the
future though, and it's potentially a useful place to add code when
debugging.
