git post-receive exception when pushing multiple refs

[Ulrik Sverdrup <ulrik sverdrup gmail com>]

Hi, I saw this exception today on the git.gnome.org servers (repo is
http://git.gnome.org/cgit/kupfer )

 ulrik $ git push origin pickle:master HEAD:dev
Counting objects: 193, done.
Compressing objects: 100% (165/165), done.
Writing objects: 100% (167/167), 24.97 KiB, done.
Total 167 (delta 125), reused 4 (delta 2)
Traceback (most recent call last):
  File "/home/admin/gitadmin-bin/gnome-post-receive-email", line 902, in ?
    main()
  File "/home/admin/gitadmin-bin/gnome-post-receive-email", line 897, in main
    change.prepare()
  File "/home/admin/gitadmin-bin/gnome-post-receive-email", line 218, in prepare
    detailed_commit_args.append("^" + all_changes[branch].oldrev)
TypeError: cannot concatenate 'str' and 'NoneType' objects
error: hooks/post-receive exited with error code 1
To ssh://usverdrup git gnome org/git/kupfer
   b95af69..bc4ec9b  pickle -> master
 * [new branch]      HEAD -> dev


Ulrik

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