diff -r 90f8fe72446c -r 3cf40112efb7 setup.py
--- a/setup.py	Tue Mar 06 18:41:08 2018 -0800
+++ b/setup.py	Tue Mar 06 18:51:11 2018 -0800
@@ -850,7 +850,6 @@
 
 xdiff_srcs = [
     'mercurial/thirdparty/xdiff/xdiffi.c',
-    'mercurial/thirdparty/xdiff/xmerge.c',
     'mercurial/thirdparty/xdiff/xprepare.c',
     'mercurial/thirdparty/xdiff/xutils.c',
 ]