I'm getting this issue after onClose connection

PHP version = 7.0.8-0ubuntu0.16.04.3
PHP memory limit = 900M
Operating system = Ubuntu 16.04
Libevent version = 2.0.22-stable
Libevent php = https://github.com/expressif/pecl-event-libevent (Reference)

Using libevent consider following log

New connection! (123)
New connection! (131)
New connection! (139)
Connection 123 has disconnected
Segmentation fault (core dumped)

Here as we can see it's stopping execution onClose and throws "Segmentation fault (core dumped)" message.
If I try without libevent then it's disconnecting clients and execution not stopping after onClose.

Sometime I'm getting following warning on onClose connection
PHP Warning: Unknown list entry type (0) in /vendor/react/event-loop/src/LibEventLoop.php on line 106