SubmittingPatches: note that trailer order matters

It matters where you put new trailers: they should be added in
chronological order, and each person who passes on a patch should add
their s-o-b last. You are signing off on the patch as well as the whole
message up to that point.

This also makes it clear who added what:

    Acked-by: The Reviewer <r@example.org>
    Signed-off-by: The Contributor <c@example.org>
    Acked-by: The (Late) Reviewer <late@example.org>
    Signed-off-by: The Maintainer <m@example.org>
The first ack was added by the contributor and the second one was added
by the maintainer.

Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches
index 125bc0a2d635661f63c59f01bde9d36ce3a01c52..56706e55ea16b8a3410b98e0eb2dcaea063528b6 100644 (file)
--- a/Documentation/SubmittingPatches
+++ b/Documentation/SubmittingPatches
@@ -427,6 +427,10 @@ D-C-O.  Indeed you are encouraged to do so.  Do not forget to
 place an in-body "From: " line at the beginning to properly attribute
 the change to its true author (see (2) above).
 
+Place this `Signed-off-by:` trailer at the end, after trailers added by
+others and after other trailers added by you; see
+<<commit-trailers,Commit trailers>> below ("chronological order").
+
 This procedure originally came from the Linux kernel project, so our
 rule is quite similar to theirs, but what exactly it means to sign-off
 your patch differs from project to project, so it may be different
@@ -487,6 +491,12 @@ particular are not used in this project.
 Only capitalize the very first letter of the trailer, i.e. favor
 `Signed-off-by:` over `Signed-Off-By:` and `Acked-by:` over `Acked-By:`.
 
+As mentioned under <<dco,DCO>> above, trailers are added in
+chronological order; one person might sign-off on a patch and send it to
+someone else, who then in turn adds her own sign-off. Further, any
+trailers that you add beyond your sign-off should come before that
+sign-off. That makes it clear what trailers which person added.
+
 [[ai]]
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