diff --git a/src/Cache/Engine/WincacheEngine.php b/src/Cache/Engine/WincacheEngine.php
index <HASH>..<HASH> 100644
--- a/src/Cache/Engine/WincacheEngine.php
+++ b/src/Cache/Engine/WincacheEngine.php
@@ -79,6 +79,7 @@ class WincacheEngine extends CacheEngine
      */
     public function get($key, $default = null)
     {
+        $success = null;
         $value = wincache_ucache_get($this->_key($key), $success);
         if ($success === false) {
             return $default;
Fix error reported by psalm.