Description:
------------
It seems that the combination of PHP 5.6 - 7.1.x, Windows Server 2012 R2 and the IIS 8.5 causes different Errors when opcache is enabled. We migrated our PHP configuration and scripts 1:1 from Windows Server 2008 and there was no Problem. But With Server 2012 we randomly get the error "Cannot redeclare class" error. The scripts work fine for 4-5 times, then the redeclare class error appeares. We tried to set the Option opcache.dups_fix = true, but without success. The only workaround was to wrap all classes with 
 if(!class_exists("Database_Zend",false)) {... } but then suddenly preg_match errors appeared.

Some error examples:

[07-Dec-2017 09:57:11 Europe/Berlin] PHP Fatal error: Cannot redeclare composerRequiree744d24db906654e872801355481e07f() (previously declared in D:\inetpub\wwwroot\itdoc\extensions\BlueSpiceFound ation\vendor\composer\autoload_real.php:63) in D:\Inetpub\wwwroot\itdoc\extensions\BlueSpiceFound ation\vendor\composer\autoload_real.php on line 63

 [11-Dec-2017 09:35:23 Europe/Berlin] PHP Warning: preg_match_all(): Compilation failed: two named subpatterns have the same name at offset 1312




Test script:
---------------
class Logfile {
 private $filename;

 public function __construct($file) {
  $this->filename = "D:/logs/".$file;
 }
}

Expected result:
----------------
No redeclare error

Actual result:
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redeclare error