Sure, the function is at app/lib/functions.php
Bottom line is that when the software gets updated, all the system files should be updated and also all the system caches. For example, I run the demo under Nginx, and after each update I have to touch (the command) all the files otherwise it remains stuck on the server cache.
At application layer I can only control OPCache, any other cache on top requieres this kind of special touch. You should check that, it is easy because you can check that the files are actually updated (you can even do a rsync on it) but the website won't display the changes even after doing a service reset. This is normal in production, and it is a caveat that always needs checking.