[php] PHP Warning: PHP Startup: ????????: Unable to initialize module

brew reinstall php56-mcrypt --build-from-source

Do this—pass the --build-from-source flag—for each module which needs to be compiled with the same version.

It may also require PHP options depending on your plugins. If so, brew reinstall php56 --with-thread-safety

To see all of the options for php[version] run brew options php56 (replacing 56 with your version)