Update runtime files
diff --git a/runtime/doc/diff.txt b/runtime/doc/diff.txt
index e5321c5..1c93de4 100644
--- a/runtime/doc/diff.txt
+++ b/runtime/doc/diff.txt
@@ -1,4 +1,4 @@
-*diff.txt*      For Vim version 9.0.  Last change: 2022 Jan 22
+*diff.txt*      For Vim version 9.0.  Last change: 2022 Oct 01
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar