Index: usr.bin/diff/diff.1
===================================================================
--- usr.bin/diff/diff.1
+++ usr.bin/diff/diff.1
@@ -92,6 +92,7 @@
 .Op Fl -ignore-case
 .Op Fl -no-ignore-case
 .Op Fl -normal
+.Op Fl -strip-trailing-cr
 .Op Fl -tabsize
 .Op Fl I Ar pattern
 .Bk -words