PHP 8.4.0RC4: Zend Observer does not work for PDO query() method when the new PDO connect() is used

Description

Problem Description
We have a custom PHP extension that registers as an observer for PDO extension's methods like __construct(), query(), etc., and our extension's handler functions get invoked when any of these PDO methods are being executed. This code is pretty generic from our side and is the same for all PDO methods we observe. But starting from PHP 8.4.0, our observer functions/function handlers are not being invoked when PDO query() method is being executed (when connect() is used) - the execution directly goes to PDO query() method instead of our registered function handlers. There is some crucial, unexplained behavioral difference I want to highlight here considering PHP introduced connect() method to create PDO objects. We adapted our code to also register observer & function handler for the new connect() method and our function handler is being invoked correctly for connect() method but not for query() method that is executed after the connect().

So:
If PDO::__construct() is used by PHP app, our extension's function handlers for __construct() AND query() are both correctly invoked by the Zend engine.
If PDO::connect() is used by PHP app, only connect() function handler in our extension is invoked but not the function handler for query().

This is inconsistent behaviour from the Zend engine.

Just to clarify how we use Zend observer API:
During MINIT:

1. We use zend_observer_fcall_register() to register begin and end function handlers.
2. We use the CG() macro to get class entry object for "PDO" class and overwrite the zend_function->internal_function_handler with our own function for __construct(), connect(), query()

We verified some aspects during runtime using a debugger :

1. Looking into the CG hashtable after we register our functions - we can confirm that zend_function->internal_function_handler for both connect() and query() hold the pointers to our extension's overwritten function handler, not the original PDO methods. 2. Inside ZEND_DO_FCALL_SPEC_OBSERVER_HANDLER() in zend_vm_execute.h from where these two functions/PDO methods are eventually invoked, we can see that the fbc->internal_function.handler for during query() execution holds some unresolved address - that is neither pointing to zim_PDO_query() or our extension's overwritten function handler.

Strange thing is, for the PDO connect() execution, fbc->internal_function.handler does point to our extension's function handler. As I said, registering observer and overwriting function handlers for these functions in the CG hashtable is generic and has been working on PHP 8.3.

PHP Version

PHP 8.4.0RC4

Operating System

No response

Reproduisez la différence entre PDO::__construct() et PDO::connect() suivi de query() en utilisant l’enregistrement de l’observer Zend et les remplacements du handler décrits dans l’issue. Commencez à ZEND_DO_FCALL_SPEC_OBSERVER_HANDLER() dans zend_vm_execute.h et inspectez les entrées PDO dans la CG hashtable ; le travail est terminé lorsque query() appelle systématiquement le handler de l’observer enregistré après connect().