diff --git a/src/pocketmine/PocketMine.php b/src/pocketmine/PocketMine.php
index 0e1fa6f67..5f816eb39 100644
--- a/src/pocketmine/PocketMine.php
+++ b/src/pocketmine/PocketMine.php
@@ -65,7 +65,6 @@ namespace {
 }
 
 namespace pocketmine {
-	use pocketmine\network\protocol\Info as ProtocolInfo;
 	use pocketmine\utils\Binary;
 	use pocketmine\utils\MainLogger;
 	use pocketmine\utils\ServerKiller;
diff --git a/src/pocketmine/command/Command.php b/src/pocketmine/command/Command.php
index 174a2a786..859bbc823 100644
--- a/src/pocketmine/command/Command.php
+++ b/src/pocketmine/command/Command.php
@@ -65,9 +65,6 @@ abstract class Command{
 	/** @var string */
 	protected $usageMessage;
 
-	/** @var string */
-	private $permission = null;
-
 	/** @var string */
 	private $permissionMessage = null;
 
diff --git a/src/pocketmine/command/CommandReader.php b/src/pocketmine/command/CommandReader.php
index 92979c432..fcfaa984d 100644
--- a/src/pocketmine/command/CommandReader.php
+++ b/src/pocketmine/command/CommandReader.php
@@ -35,7 +35,6 @@ class CommandReader extends Thread{
 	protected $buffer;
 	private $shutdown = false;
 	private $type = self::TYPE_STREAM;
-	private $lastLine = -1;
 
 	public function __construct(){
 		$this->buffer = new \Threaded;
@@ -89,6 +88,7 @@ class CommandReader extends Thread{
 	/**
 	 * Checks if the specified stream is a FIFO pipe.
 	 *
+	 * @param resource $stream
 	 * @return bool
 	 */
 	private function isPipe($stream) : bool{
diff --git a/src/pocketmine/level/format/io/ChunkUtils.php b/src/pocketmine/level/format/io/ChunkUtils.php
index 6fbc56934..934ab46b2 100644
--- a/src/pocketmine/level/format/io/ChunkUtils.php
+++ b/src/pocketmine/level/format/io/ChunkUtils.php
@@ -36,8 +36,6 @@ class ChunkUtils{
 		$result = str_repeat("\x00", 4096);
 		if($array !== $result){
 			$i = 0;
-			$zM = 0;
-			$yM = 0;
 			for($x = 0; $x < 16; ++$x){
 				$zM = $x + 256;
 				for($z = $x; $z < $zM; $z += 16){
diff --git a/src/pocketmine/wizard/Installer.php b/src/pocketmine/wizard/Installer.php
index 5e9676104..f6f3c8ee2 100644
--- a/src/pocketmine/wizard/Installer.php
+++ b/src/pocketmine/wizard/Installer.php
@@ -58,13 +58,13 @@ class Installer{
 		$this->lang = new InstallerLang($lang);
 
 
-		echo "[*] " . $this->lang->language_has_been_selected . "\n";
+		echo "[*] " . $this->lang->get("language_has_been_selected") . "\n";
 
 		if(!$this->showLicense()){
 			return false;
 		}
 
-		echo "[?] " . $this->lang->skip_installer . " (y/N): ";
+		echo "[?] " . $this->lang->get("skip_installer") . " (y/N): ";
 		if(strtolower($this->getInput()) === "y"){
 			return true;
 		}