This addresses bug #71269.
When an fpm child handles more than one request, zend_signal_startup() will
override the saved signal handlers with the internal zend handlers set from the
previous request, causing a SIGQUIT signal to result in a core dump rather than
gracefully exiting (the expected behaviour).
This is fixed by adding a call to zend_signal_init() after setting the
signal handlers in the child. The same technique is used in the apache SAPI
module in commit fd5a756ad4 which addresses
bug #61083.
0c2e184eac