Bug #78565 [Com]: Shutdown functions are not called when exit is called from output handler

Edit report at https://bugs.php.net/bug.php?id=78565&edit=1 ID: 78565 Comment by: video dot ice dot power at seznam dot cz Reported by: video dot ice dot power at seznam dot cz Summary: Shutdown functions are not called when exit is called from output handler Status: Feedback Type: Bug Package: *General Issues Operating System: Debian 9 PHP Version: 7.3.9 Assigned To: cmb Block user comment: N Private report: N New Comment: https://3v4l.org/ZoBJs - "shutting down" text is not printed Previous Comments: ------------------------------------------------------------------------ [2021-04-06 17:11:26] cmb@php.net I cannot reproduce this; I get (PHP-7.3 and -7.4 on Windows, and PHP-7.4 on Debian): Fatal error: ob_flush(): Cannot use output buffering in output buffering display handlers So, apparently, the shutdown handler is executed. What am I missing? ------------------------------------------------------------------------ [2019-12-17 18:25:57] archon810 at gmail dot com We've been trying to figure out why Sentry doesn't fire in AMP and arrived at the same conclusion - lack of the register_shutdown_function call when in ob_, which is used by AMP. Please see https://github.com/getsentry/sentry-php/issues/927 and https://github.com/ampproject/amp-wp/issues/3825. If any PHP core devs would chime in, that'd be great. Thank you. ------------------------------------------------------------------------ [2019-09-19 07:41:42] video dot ice dot power at seznam dot cz Description: ------------ Shutdown functions are not called when exit is called from output handler Test script: --------------- <?php // capture any unexpected output and exit execution ob_start(function($buffer) { echo 'unexpected output: ' . $buffer . "\n"; exit; }, 1); // do some work on shutdown register_shutdown_function(function() { ob_flush(); ob_end_clean(); echo 'shutting down'; }); echo 'x'; Expected result: ---------------- unexpected output: x shutting down Actual result: -------------- (empty result) ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=78565&edit=1