Drupal warning "RabbitMQ Consumer extension PCNTL not present in PHP" when using PHP-FPM

Problem/Motivation

When running PHP using PHP-FPM, Drupal display the following warning on the Status Report page (/admin/reports/status)

"Extension PCNTL not present in PHP. Option rabbitmq_timeout is not available in the RabbitMQ consumer."

However the PCNTL module is only available for the PHP command line interpreter.

https://stackoverflow.com/questions/35026153/call-to-undefined-function-...

Hence the warning will be displayed whether the PCNTL module is enabled for PHP or not.

Steps to reproduce

Install and run a Drupal installation under PHP-FPM with RabbitMQ module installed.

Proposed resolution

A solution could be to execute the check with PHP CLI through exec() or system()

https://stackoverflow.com/questions/15717168/checking-pcntl-extension-in...