System log is designed to log all errors, that happen during script execution. Unfortunately fatal errors, that are not displayed to end user are never logged.
This happens due
exit; statement after fatal error message is displayed in the
I think that we should take approach from [debugger] Debugger blocks fatal error/exception tracking by System Log [5.2.1] and only exit if we're not already in
register_shutdown_function callback. The fix for [system log] Special template for fatal errors and uncatched exceptions [5.3.0-B1] should add that
applicationShutdown flag I'm talking about here.