[php-src] Issue #9381: MYSQL_ATTR_INIT_COMMAND causing "The FastCGI process exited unexpectedly"

Issue: https://github.com/php/php-src/issues/9381 Author: HeavenCore ### Description We have some PHP code that has ran fine for years under PHP 7 / IIS / FastCGI When updating to PHP 8.1.9 we're getting "The FastCGI process exited unexpectedly" After digging through the code we have identified the issue as follows: When using PDO::MYSQL_ATTR_INIT_COMMAND in the new PDO() constructor - FastCGI just dies ```php $options = [ PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC, PDO::ATTR_EMULATE_PREPARES => false, PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8mb4;" ]; $this->m_db = new PDO( $m_PDOConnectionString, $Username, $Password, $options ); ``` Resulted in this output: ``` C:\Program Files (x86)\PHP\v8.1.9.dev\php-cgi.exe - The FastCGI process exited unexpectedly ``` But I expected this output instead: ``` N/A - expected DB connection to open as normal ``` Only thing i can find in the windows event log is as follows: ``` Faulting application name: php-cgi.exe, version: 8.1.9.0, time stamp: 0x62e93213 Faulting module name: php8.dll, version: 8.1.9.0, time stamp: 0x62e93aac Exception code: 0xc0000005 Fault offset: 0x00008fac Faulting process id: 0x4d4 Faulting application start time: 0x01d8b3db35c39991 Faulting application path: C:\Program Files (x86)\PHP\v8.1.9.dev\php-cgi.exe Faulting module path: C:\Program Files (x86)\PHP\v8.1.9.dev\php8.dll Report Id: 3737167c-6b9f-48b2-bdfb-74baff4570ec Faulting package full name: Faulting package-relative application ID: ``` Removing MYSQL_ATTR_INIT_COMMAND solves the prooblem and everything starts working again. The systax we're using here, i.e. "SET NAMES utf8mb4;" is a valid MySQL command which we've tested in mySQL workbench etc Is this related to https://github.com/php/php-src/issues/9143 i wonder? ### PHP Version 8.1.9 ### Operating System Windows Server 2019