When trying to install APCu via brew I get the error
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/opt/php56-apcu/apcu.so' - dlopen(/usr/local/opt/php56-apcu/apcu.so, 9): Symbol not found: _zend_signal_globals Referenced from: /usr/local/opt/php56-apcu/apcu.so Expected in: flat namespace in /usr/local/opt/php56-apcu/apcu.so in Unknown on line 0
This occurs no matter how I install APCu
brew install php56-apcu
brew install --build-from-source php56-apcu
brew install php56-apcu --enable-apc-bc
APC fails to appear in phpinfo too.
Opcache is install fine, as is php-intl
the executable in /usr/bin/php would necessarily be the apple distribution php on El-Capitan (cant be certain about previous versions, OSX is such a moving target).
Try to add /usr/local/bin as top dog in your path (in file .bash_profile) and retry in a newly instantiated terminal window.