php.ini:
ffi.enable=preload
opcache.preload=/app/preload.php

native.h:
#define FFI_SCOPE "NATIVE_MATH"
#define FFI_LIB "libc.so.6"
int abs(int value);

preload.php:
<?php
FFI::load(__DIR__ . '/native.h');

application.php:
<?php
$ffi = FFI::scope('NATIVE_MATH');
echo $ffi->abs(-8), "\n";
