BCgen is derived from the Zend OPcache source code.
It provides a single function to compile a PHP script into binary bytecode file. BCgen is similiar to bcompiler, but not a direct replacement.
Only PHP-7.2 is supported for now. There are currently no plans to support earlier PHP versions as well. Supporting different PHP versions with their different internal data structures is really a hassle.
So if you distribute your BCGen compiled PHP files to protect your code, make sure that the user uses the correct PHP version that matches the BCgen version. In times of docker et al it should not be a problem to achieve this.
Compile
$PHP_DIR/bin/phpize ./configure \ --with-php-config=$PHP_DIR/bin/php-config make
Install
make install # this will copy bcgen.so into PHP extension directory
Edit php.ini
zend_extension=/...full path.../bcgen.so
NOTE: In case you are going to use BCgen together with Xdebug or Zend Debugger, be sure that the debugger is loaded after BCgen. "php -v" must show the debugger after BCgen.
bcgen.enable (default "1") BCgen On/Off switch. When set to Off, bytecode files cannot be read
bcgen.save_comments (default "1") If disabled, all PHPDoc comments are dropped from the code to reduce the size of the optimized code. Disabling "Doc Comments" may break some existing applications and frameworks (e.g. Doctrine, ZF2, PHPUnit)
bcgen.optimization_level (default "0xffffffff") A bitmask, where each bit enables or disables the appropriate BCgen passes
bcgen.dups_fix (default "0") Enable this hack as a workaround for "Cannot redeclare class" errors.
bcgen.file_consistency_checks (default "0") Check the file checksum on each request. The default value of "0" means that the check is disabled. Because calculating the checksum impairs performance, this directive should be enabled only as part of a debugging process.
bcgen.error_log BCgen error_log file name. Empty string assumes "stderr".
bcgen.log_verbosity_level (default "1") All BCgen errors go to the Web server log. By default, only fatal errors (level 0) or errors (level 1) are logged. You can also enable warnings (level 2), info messages (level 3) or debug messages (level 4).