krt@ubuntu:~/src/fdroiddata$ fdroid build -v -t -l --no-tarball org.mozilla.fennec_fdroid
DEBUG: Reading config.py
DEBUG: Getting hg vcs interface for https://hg.mozilla.org/releases/mozilla-release/
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > hg status -uS
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > rm -rf mobile/android/base/java/org/mozilla/gecko/GeckoApp.java.orig
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > rm -rf mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java.orig
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > rm -rf mobile/android/base/moz.build.orig
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > rm -rf used-locales
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > hg pull
DEBUG: Directory: build/org.mozilla.fennec_fdroid
DEBUG: > hg update -C HEAD
Traceback (most recent call last):
  File "/home/krt/tmp/fdroid/fdroidserver/fdroid", line 148, in <module>
    main()
  File "/home/krt/tmp/fdroid/fdroidserver/fdroid", line 124, in main
    mod.main()
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/build.py", line 1104, in main
    allapps = metadata.read_metadata(not options.onserver, pkgs)
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/metadata.py", line 829, in read_metadata
    app = parse_metadata(metadatapath, packageName in check_vcs)
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/metadata.py", line 1016, in parse_metadata
    vcs.gotorevision('HEAD')  # HEAD since we can't know where else to go
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/common.py", line 617, in gotorevision
    raise exc
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/common.py", line 606, in gotorevision
    self.gotorevisionx(rev)
  File "/home/krt/tmp/fdroid/fdroidserver/fdroidserver/common.py", line 915, in gotorevisionx
    raise VCSException("Hg checkout of '%s' failed" % rev, p.output)
fdroidserver.common.VCSException: Hg checkout of 'HEAD' failed
==== detail begin ====
abort: unknown revision 'HEAD'!
==== detail end ====