diff --git a/lib/SimpleSAML/Store/Memcache.php b/lib/SimpleSAML/Store/Memcache.php
index 209ae762f3672a58913838350a14656990d237f0..01739072e49a8785f6fde2e833ec6f1dfafb07d8 100644
--- a/lib/SimpleSAML/Store/Memcache.php
+++ b/lib/SimpleSAML/Store/Memcache.php
@@ -52,7 +52,8 @@ class Memcache extends Store
      * @param string $type The data type.
      * @param string $key The key.
      * @param mixed $value The value.
-     * @param int|NULL $expire  The expiration time (unix timestamp), or NULL if it never expires.
+     * @param int|null $expire The expiration time (unix timestamp), or NULL if it never expires.
+     * @return void
      */
     public function set($type, $key, $value, $expire = null)
     {
@@ -73,6 +74,7 @@ class Memcache extends Store
      *
      * @param string $type The data type.
      * @param string $key The key.
+     * @return void
      */
     public function delete($type, $key)
     {
diff --git a/lib/SimpleSAML/Store/Redis.php b/lib/SimpleSAML/Store/Redis.php
index 310caa98f42cb480cc1e8d17102a20d7f7c0cc82..53c27f4549c333c95953f61b7f2e168e37c7c20e 100644
--- a/lib/SimpleSAML/Store/Redis.php
+++ b/lib/SimpleSAML/Store/Redis.php
@@ -12,10 +12,12 @@ use \SimpleSAML\Store;
  */
 class Redis extends Store
 {
+    /** @var \Predis\Client */
     public $redis;
 
     /**
      * Initialize the Redis data store.
+     * @param \Predis\Client|null $redis
      */
     public function __construct($redis = null)
     {
@@ -87,6 +89,7 @@ class Redis extends Store
      * @param string $key The key to insert.
      * @param mixed $value The value itself.
      * @param int|null $expire The expiration time (unix timestamp), or null if it never expires.
+     * @return void
      */
     public function set($type, $key, $value, $expire = null)
     {
@@ -109,6 +112,7 @@ class Redis extends Store
      *
      * @param string $type The type of the data
      * @param string $key The key to delete.
+     * @return void
      */
     public function delete($type, $key)
     {
diff --git a/lib/SimpleSAML/Store/SQL.php b/lib/SimpleSAML/Store/SQL.php
index 72bb84248cefd72baf526943579cbafedca2e982..175d15c67f2aae9b5756fdda44df0f9c20b5a825 100644
--- a/lib/SimpleSAML/Store/SQL.php
+++ b/lib/SimpleSAML/Store/SQL.php
@@ -77,6 +77,7 @@ class SQL extends Store
 
     /**
      * Initialize the table-version table.
+     * @return void
      */
     private function initTableVersionTable()
     {
@@ -100,6 +101,7 @@ class SQL extends Store
 
     /**
      * Initialize key-value table.
+     * @return void
      */
     private function initKVTable()
     {
@@ -185,6 +187,7 @@ class SQL extends Store
      *
      * @param string $name Table name.
      * @param int $version Table version.
+     * @return void
      */
     public function setTableVersion($name, $version)
     {
@@ -208,6 +211,7 @@ class SQL extends Store
      * @param string $table The table we should update.
      * @param array $keys The key columns.
      * @param array $data Associative array with columns.
+     * @return void
      */
     public function insertOrUpdate($table, array $keys, array $data)
     {
@@ -266,6 +270,7 @@ class SQL extends Store
 
     /**
      * Clean the key-value table of expired entries.
+     * @return void
      */
     private function cleanKVStore()
     {
@@ -329,6 +334,7 @@ class SQL extends Store
      * @param string $key The key to insert.
      * @param mixed $value The value itself.
      * @param int|null $expire The expiration time (unix timestamp), or null if it never expires.
+     * @return void
      */
     public function set($type, $key, $value, $expire = null)
     {
@@ -367,6 +373,7 @@ class SQL extends Store
      *
      * @param string $type The type of the data
      * @param string $key The key to delete.
+     * @return void
      */
     public function delete($type, $key)
     {