From 8c47ada2de6b62a82053c484a5502688e200c14d Mon Sep 17 00:00:00 2001
From: c-bata <c-bata@users.noreply.github.com>
Date: Sun, 29 Oct 2023 13:56:15 +0900
Subject: [PATCH] gh-66425: Remove the unreachable code to set `REMOTE_HOST`
 header (gh-111441)

---
 Lib/wsgiref/simple_server.py                                  | 4 ----
 .../Library/2023-10-29-03-46-27.gh-issue-66425.FWTdDo.rst     | 3 +++
 2 files changed, 3 insertions(+), 4 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2023-10-29-03-46-27.gh-issue-66425.FWTdDo.rst

diff --git a/Lib/wsgiref/simple_server.py b/Lib/wsgiref/simple_server.py
index 93d01a863ad..a0f2397fcf0 100644
--- a/Lib/wsgiref/simple_server.py
+++ b/Lib/wsgiref/simple_server.py
@@ -84,10 +84,6 @@ class WSGIRequestHandler(BaseHTTPRequestHandler):
 
         env['PATH_INFO'] = urllib.parse.unquote(path, 'iso-8859-1')
         env['QUERY_STRING'] = query
-
-        host = self.address_string()
-        if host != self.client_address[0]:
-            env['REMOTE_HOST'] = host
         env['REMOTE_ADDR'] = self.client_address[0]
 
         if self.headers.get('content-type') is None:
diff --git a/Misc/NEWS.d/next/Library/2023-10-29-03-46-27.gh-issue-66425.FWTdDo.rst b/Misc/NEWS.d/next/Library/2023-10-29-03-46-27.gh-issue-66425.FWTdDo.rst
new file mode 100644
index 00000000000..e7ede35891f
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-10-29-03-46-27.gh-issue-66425.FWTdDo.rst
@@ -0,0 +1,3 @@
+Remove the code to set the REMOTE_HOST header from wsgiref module,
+as it is unreachable. This header is used for performance reasons,
+which is not necessary in the wsgiref module.