This isn't the first time something like this has been done; for a while Facebook used a PHP to C++ compiler before switching to compiling it directly to native

This isn't the first time something like this has been done; for a while Facebook used a PHP to C++ compiler before switching to compiling it directly to native code via a JIT: https://en.wikipedia.org/wiki/HipHop_for_PHP https://en.wikipedia.org/wiki/HipHop_for_PHP https://en.wikipedia.org/wiki/HHVM https://en.wikipedia.org/wiki/HHVM