diff --git a/Documentation/dontdiff b/Documentation/dontdiff
index feae2168634b..881e6dd03aea 100644
--- a/Documentation/dontdiff
+++ b/Documentation/dontdiff
@@ -172,6 +172,7 @@ sm_tbl*
 split-include
 tags
 tftpboot.img
+timeconst.h
 times.h*
 tkparse
 trix_boot.h