Before sending it to Cleanup, is the wmerrors PHP extension still useful? In T56163: Port wmerrors / php-fatal-error.html to HHVM it was decided that we didn't need this for HHVM, will we need it again for PHP 7? Or can it be safely archived?
- Recoverable and unrecoverable fatal errors have events emitted on PHP 7.2 similar to how HHVM provided these (except PHP7 uses a Throwable as uncaught exception, instead of an Error event; MediaWiki already tracks both).
- No stack traces, at all, for PHP 7 fatal errors. HHVM provided these through a custom mechanism. For PHP 5, we had a custom extension. We might need that again, or find a different clever workaround if possible.
- Changes to rsyslog/Kafka mean that large errors are now completely lost instead of truncated. More info at T187147#5165518. (fixed with https://phabricator.wikimedia.org/T187147#5182892)
- Catchable fatals are reported as exceptions (in exception.log) and use our custom fatal error page handler.