diff --git a/src/Servers/HttpSys/src/UrlPrefixCollection.cs b/src/Servers/HttpSys/src/UrlPrefixCollection.cs
index e29d1737d8..f15e96c478 100644
--- a/src/Servers/HttpSys/src/UrlPrefixCollection.cs
+++ b/src/Servers/HttpSys/src/UrlPrefixCollection.cs
@@ -4,6 +4,8 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
 using Microsoft.AspNetCore.Http;
 
 namespace Microsoft.AspNetCore.Server.HttpSys