Index: core/install/install_toolkit.php
===================================================================
--- core/install/install_toolkit.php
+++ core/install/install_toolkit.php
@@ -583,6 +583,10 @@
 
 			fclose($fp);
 
+			if ( function_exists('opcache_invalidate') ) {
+				opcache_invalidate($this->INIFile);
+			}
+
 			$this->systemConfigChanged = false;
 		}
 
@@ -1180,4 +1184,4 @@
 
 			return $compression_engines;
 		}
-	}
\ No newline at end of file
+	}