Bug #81442 [Opn->Nab]: Deprecation warning(?) does not trigger error handler

Edit report at https://bugs.php.net/bug.php?id=81442&edit=1 ID: 81442 Updated by: nikic@php.net Reported by: rkaiser at gmail dot com Summary: Deprecation warning(?) does not trigger error handler -Status: Open +Status: Not a bug Type: Bug Package: Unknown/Other Function Operating System: CentOS 7.7 PHP Version: 8.0.10 Block user comment: N Private report: N New Comment: An error handler cannot catch a *compile-time* deprecation warning in the same file. It will work just fine for warnings in other files though. Previous Comments: ------------------------------------------------------------------------ [2021-09-15 18:50:32] rkaiser at gmail dot com Description: ------------ If you have a function with parameter with a default value preceding a required parameter (https://www.php.net/manual/en/migration80.deprecated.php), you get a deprecation warning (or notice? not clear which it is). However this warning doesn't get caught by set_error_handler() for some reason. I first noticed this while using opcache (see https://bugs.php.net/bug.php?id=73665) but then noticed it repros even without opcache enabled. Test script: --------------- set_error_handler(function ($errno, $errstr, $errfile, $errline) { // This never hits die('caught in error handler'); }); function test($a = 1, $b ) { echo 'this executes'; } // Displays "Deprecated: Required parameter $b follows optional parameter $a" test(null, null); Expected result: ---------------- I would expect the error handler to catch this warning. Actual result: -------------- Function executes and displays the warning. If set_error_handler() is not supposed to catch this, is there another mechanism in PHP 8 to catch this warning at runtime? It's often not practical to fix the references in 3rd party code that hasn't been updated for PHP 8 yet. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=81442&edit=1