PHP JIT disabled because of incompatible extensions
Recently we had a case where a customer noticed that the PHP JIT is disabled because of the following error message:
PHP message: PHP Warning: JIT is incompatible with third party extensions that override zend_execute_ex(). JIT disabled
According to the website PHP Internals Book the zend_execute_ex
hook gets overridden by extensions that provide profiling or debugging functionality. Overriding this hook however makes it impossible to use the PHP JIT.
So basically extensions like Xdebug, pvoc but also tools like Blackfire.