After upgrading HHVM to version 3.10 from 3.9.1 and rebuilding luasandbox (`sudo hphpize && cmake . && sudo make install && sudo service hhvm restart`) luasandox is enabled: `phpinfo ()` shows:
```
hhvm.dynamic_extensions = Array ( [0] => luasandbox.so )
...
hhvm.enable_zend_compat = 1
```
However, luasandbox doesn't work, the class `Luasandbox` does not exist and `/var/log/hhvm/error.log` says `Fatal error: Class undefined: LuaSandbox in (path to MediaWiki)/extensions/Scribunto/engines/LuaSandbox/Engine.php on line 17`.
Upgrading luasandbox didn't help.
If I run `hhvm luasandbox.php` this is what I get:
```
Fatal error: f_get_extension_funcs is not supported: extensions are built differently in (path to MediaWiki)/extensions/luasandbox/luasandbox.php on line 8
```
Upgrade: I downgraded HHVM to 3.9.1 and then to 3.9 but the issue remained. I suspect now, that the error is in LuaSandbox.