[Feature] get where "exit" was called/shutdown started

[kkmuffme]

Description

There currently is no simple way to figure out what/where exit was called.

Since PHP 8.4 PHP is a proper function, however it seems it's xdebug won't break on it, even if set (besides the fact, there's tons of bugs with IDEs/xdebug when breaking on built-in functions, e.g. defined()

Stepping through the code until exit; is reached isn't feasible in all cases (it happens in a long running process, this might take a day...)

It would be great if there were a magic constant similar to __COMPILER_HALT_OFFSET__ that is available in shutdown function callbacks, which includes the last executed file + line in the main thread before shutdown started. But that's just a simple first suggestion, I'm open to everything that makes identifying/debugging this easier.

[iluuu1994]

Why not propose this as an xdebug feature instead? I don't think there's a technical reason why xdebug cannot intercept exit calls.

[kkmuffme]

I don't think there's a technical reason why xdebug cannot intercept exit calls.

Afaik bc in < PHP 8.4 exit wasn't an actual function. Not sure if it's possible in PHP 8.4, as I couldn't test that yet.

However this is a common-ish scenario for cases where xdebug isn't easily available.

[iluuu1994]

Afaik bc in < PHP 8.4 exit wasn't an actual function.

Yes, but it had an ZEND_EXIT opcode that could have been hooked into. With 8.4 being a dedicated function, xdebug may require a different trigger. It's possible this already works, but I don't know xdebug that well. /cc @derickr

[kkmuffme]

See error report in xdebug https://bugs.xdebug.org/view.php?id=2274

EDIT: which by the way is only helpful if we're not in shutdown already. Checking what calls exit in a shutdown is impossible, since there's nothing that would run after it, therefore can't print/log the output of the function monitor either. The only option would be a breakpoint.
The suggested feature would have the same issue too, I guess this needs some thought on what would actually make sense to cover that case too