Description:
------------
simple mariadb PDO connect and give result after success...

when Database is available all worked fine.... shut down DB instance manual and host is not available call simple php script with this function...

if Database is down catch block will not work and php is working and after that following Message appear.

Fatal error: Allowed memory size of 629145600 bytes exhausted (tried to allocate 20480 bytes)

my php function shows like this.



the Code worked before,source code have never changed.
tested with arbitrary php_memory limit,but the issue is still available...

testet with php 5.6,7.0,7.1 (default)...

it works fine with 7.1,but have no idea...

timeout array in PDO constructor have also removed...


Test script:
---------------
> function getDBConnection()
> {
>     global $pdo;
>     try {
>         if ($pdo == null)
>             $pdo = new PDO(
>            
>                 'mysql:host=databaseHost;dbname=someDatabase;charset=utf8mb4',
>                 'removed',
>                 'removed_too'
>             );
>     } catch (Exception $ex) {
>         
>         generateErrorPlistWithFailReason(ErrorCodes::DATABASE_IS_DOWN, 
>         exit();
>     }
>     return $pdo;
> }



Expected result:
----------------
resource result and or result from catch block (if databse is down/notavailable)...

Actual result:
--------------
after timeout 

Fatal error: Allowed memory size of 629145600 bytes exhausted (tried to allocate 20480 bytes)