gistfile1.txt

$ git init one
Initialized empty Git repository in /tmp/one/.git/
$ (cd one && echo one > one && git add one && git commit -m one)
[master (root-commit) 5428241] one
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 one
$ git clone --bare one two.git
Cloning into bare repository two.git...
done.
$ (cd one && echo two > two && git add two && git commit -m two)
[master abb3df4] two
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 two
$ git --git-dir=two.git fetch
remote: Counting objects: 4, done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
From /tmp/one
 * branch            HEAD       -> FETCH_HEAD
$ git --git-dir=one/.git log --pretty=format:%h
abb3df4
5428241
$ git --git-dir=two.git log --pretty=format:%h
5428241

    ^ expected same result for last two