symfony
diff --git a/‎src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
+23-1Lines changed: 23 additions & 1 deletion b/‎src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
+23-1Lines changed: 23 additions & 1 deletion
diff --git a/‎src/Symfony/Component/HttpFoundation/Session/Storage/Proxy/SessionHandlerProxy.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/HttpFoundation/Session/Storage/Proxy/SessionHandlerProxy.php
+8Lines changed: 8 additions & 0 deletions b/‎src/Symfony/Component/HttpFoundation/Session/Storage/Proxy/SessionHandlerProxy.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/HttpFoundation/Session/Storage/Proxy/SessionHandlerProxy.php
+8Lines changed: 8 additions & 0 deletions
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\HttpFoundation\Session\Storage;
 
+use Symfony\Component\Debug\Exception\ContextErrorException;
 use Symfony\Component\HttpFoundation\Session\SessionBagInterface;
 use Symfony\Component\HttpFoundation\Session\Storage\Handler\NativeSessionHandler;
 use Symfony\Component\HttpFoundation\Session\Storage\Proxy\AbstractProxy;
@@ -208,7 +209,28 @@ public function regenerate($destroy = false, $lifetime = null)
      */
     public function save()
     {
-        session_write_close();
+        // Register custom error handler to catch a possible failure warning during session write
+        set_error_handler(function ($errno, $errstr, $errfile, $errline, $errcontext) {
+            throw new ContextErrorException($errstr, $errno, E_WARNING, $errfile, $errline, $errcontext);
+        }, E_WARNING);
+
+        try {
+            session_write_close();
+            restore_error_handler();
+        } catch (ContextErrorException $e) {
+            // The default PHP error message is not very helpful, as it does not give any information on the current save handler.
+            // Therefore, we catch this error and trigger a warning with a better error message
+            $handler = $this->getSaveHandler();
+            if ($handler instanceof SessionHandlerProxy) {
+                $handler = $handler->getHandler();
+            }
+
+            restore_error_handler();
+            trigger_error(sprintf(
+                'session_write_close(): Failed to write session data with %s handler',
+                get_class($handler)
+            ), E_USER_WARNING);
+        }
 
         $this->closed = true;
         $this->started = false;
 
@@ -35,6 +35,14 @@ public function __construct(\SessionHandlerInterface $handler)
         $this->saveHandlerName = $this->wrapper ? ini_get('session.save_handler') : 'user';
     }
 
+    /**
+     * @return \SessionHandlerInterface
+     */
+    public function getHandler()
+    {
+        return $this->handler;
+    }
+
     // \SessionHandlerInterface
 
     /**