Warning :Remote branch XXX.. not found in upstream origin, using HEAD instead when cloning xen source

When you clone git repository for xen 4.3, you would get the following message:
"Remote branch RELEASE-4.3.0 not found in upstream origin, using HEAD instead"

This is caused because of git version, prior version to 1.7.10 don't support checking out tag.

# My git version 
$ git --version
git version 1.7.9.5

# Download Xen source
$ git clone -b RELEASE-4.3.0 git://xenbits.xen.org/xen.git
Cloning into 'xen'...
remote: Counting objects: 272877, done.
remote: Compressing objects: 100% (55538/55538), done.
remote: Total 272877 (delta 214914), reused 270399 (delta 212700)
Receiving objects: 100% (272877/272877), 53.61 MiB | 1.75 MiB/s, done.
Resolving deltas: 100% (214914/214914), done.

warning: Remote branch RELEASE-4.3.0 not found in upstream origin, using HEAD instead

Simply, you are able to check out additionally.

$ cd xen
$ git checkout RELEASE-4.3.0
Note: checking out 'RELEASE-4.3.0'.

Or, you can re-install the newer version of git.

# Remove the old git
$ sudo apt-get remove git

# Download git
$ wget https://git-core.googlecode.com/files/git-1.8.1.2.tar.gz
$ tar -xzvf ./git-1.8.1.2.tar.gz
$ cd git-1.8.1.2
$ make prefix=/usr/local all
$ sudo make prefix=/usr/local install
$ git --version
git version 1.8.1.2

# Download Xen source 
$ git clone -b RELEASE-4.3.0 git://xenbits.xen.org/xen.git
Cloning into 'xen'...
remote: Counting objects: 272877, done.
remote: Compressing objects: 100% (55538/55538), done.
remote: Total 272877 (delta 214914), reused 270399 (delta 212700)
Receiving objects: 100% (272877/272877), 53.61 MiB | 4.01 MiB/s, done.
Resolving deltas: 100% (214914/214914), done.
Note: checking out 'f8cc9c2b713b1739b1d3d324716547fa639dce86'.

References:
1. http://stackoverflow.com/questions/17216067/git-clone-b-tag-results-in-warning-remote-branch-not-found-in-upstream-origi/17216068#17216068