From f6be54a4b856d276420dbbf14552557bd7f45df8 Mon Sep 17 00:00:00 2001
From: Roman Podymov <podymfrombryansk@yandex.ru>
Date: Sat, 11 May 2019 02:35:34 +0200
Subject: [PATCH] handle possible unknown queues

---
 Sources/Async/Async.swift | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Sources/Async/Async.swift b/Sources/Async/Async.swift
index 4c1b5b9..818ec64 100644
--- a/Sources/Async/Async.swift
+++ b/Sources/Async/Async.swift
@@ -762,6 +762,7 @@ public extension DispatchQoS.QoSClass {
             case .utility: return "Utility"
             case .background: return "Background"
             case .unspecified: return "Unspecified"
+            @unknown default: return "Unknown"
             }
         }
     }