From mboxrd@z Thu Jan  1 00:00:00 1970
From: skillzero@gmail.com
Subject: Redundant merges?
Date: Wed, 30 Sep 2009 14:15:50 -0700
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Is there a way to avoid redundant merges when merging maint to master
if both maint and master have already merged in the same topic
branches? For example, assuming the git.git repository:

1. A bug was found and a topic branch (with a merge-base at or before
maint) is created with the fix.
2. The fix looks good so it's merged into master.
3. maint is already past the freeze date so the fix isn't merged into
maint (bug is not super critical).
4. maint is delayed for some reason and is accepting fixes.
5. Topic branch from step 1 is merged into maint.
6. maint is merged into master.

What I see is two merge commits that merge the same topic. I think I
understand why it's doing this (the merge commit is just another
commit so it merges it). But could it look at what the merge did and
realize that it already has the commit that the merge commit merged
and do nothing in this case?