diff --git a/.hgeol b/.hgeol
index 05557851c98..eb19a6c88d2 100644
--- a/.hgeol
+++ b/.hgeol
@@ -40,6 +40,9 @@ Lib/venv/scripts/nt/* = BIN
 
 Lib/test/coding20731.py = BIN
 
+# Windows only zlib upstream file
+Modules/zlib/zlib.map = CRLF
+
 # Windows batch files work best with CRLF, there can be subtle problems with LF
 **.bat = CRLF