fetch_orig_from_pristine_tar failed, fetched from upstream, crashed with FileExistsError

[Andreas Hasenack]

(cosmic-apache2-2.4.33-3)andreas@nsnx:~/git/packages/apache2$ git ubuntu build-source -v --lxd-image ubuntu-bionic --for-merge 2>&1 | tee ../build
05/09/2018 16:38:47 - DEBUG:Executing: git config gitubuntu.lpuser
05/09/2018 16:38:47 - DEBUG:Executing: grep -q "* -ident" /home/andreas/git/packages/apache2/.git/info/attributes
05/09/2018 16:38:47 - DEBUG:Executing: grep -q "* -text" /home/andreas/git/packages/apache2/.git/info/attributes
05/09/2018 16:38:47 - DEBUG:Executing: grep -q "* -eol" /home/andreas/git/packages/apache2/.git/info/attributes
05/09/2018 16:38:47 - DEBUG:Executing: git config gitubuntu.lpuser
05/09/2018 16:38:47 - DEBUG:Executing: sh -c "dpkg-parsechangelog -l- -n1 -SVersion"
05/09/2018 16:38:47 - DEBUG:Executing: git status --porcelain
05/09/2018 16:38:47 - DEBUG:Executing: sh -c "dpkg-parsechangelog -l- -n1 -SVersion"
05/09/2018 16:38:47 - DEBUG:Executing: sh -c "dpkg-parsechangelog -l- -n1 -o1 -SVersion"
05/09/2018 16:38:48 - DEBUG:Executing: sh -c "dpkg-parsechangelog -l- -SSource"
05/09/2018 16:38:48 - DEBUG:fetch_orig_from_parent_dir(source=None) failed
05/09/2018 16:38:48 - DEBUG:fetch_orig_from_cache(source=debian) failed
05/09/2018 16:38:48 - DEBUG:Executing: pristine-tar list
05/09/2018 16:38:48 - DEBUG:Executing: pristine-tar list
05/09/2018 16:38:48 - DEBUG:Executing: pristine-tar list
05/09/2018 16:38:48 - DEBUG:Executing: gbp buildpackage --git-builder=/bin/true --git-pristine-tar --git-ignore-branch '--git-upstream-tag=pkg/upstream/debian/%(version)s.bz2'
05/09/2018 16:38:52 - ERROR:Command exited 1: gbp buildpackage --git-builder=/bin/true --git-pristine-tar --git-ignore-branch '--git-upstream-tag=pkg/upstream/debian/%(version)s.bz2'
05/09/2018 16:38:52 - ERROR:stdout: gbp:info: Creating /home/andreas/git/packages/apache2_2.4.33.orig.tar.bz2

05/09/2018 16:38:52 - ERROR:stderr: gbp:error: Pristine-tar couldn't verify "apache2_2.4.33.orig.tar.bz2": pristine-tar: /home/andreas/git/packages/apache2_2.4.33.orig.tar.bz2 does not match stored hash (expected de02511859b00d17845b9abdd1f975d5ccb5d0b280c567da5bf2ad4b70846f05, got 456884756cc95c86ce63da584e46e4c281960998db58b33f30f80b515926cba1)

05/09/2018 16:38:52 - DEBUG:fetch_orig_from_pristine_tar(source=debian) failed
05/09/2018 16:38:58 - DEBUG:Checking if upstream version of publish 2.4.33-3 matches 2.4.33
05/09/2018 16:38:58 - DEBUG:Upstream version of publish 2.4.33-3 matches
05/09/2018 16:39:09 - DEBUG:Verifying orig tarball /home/andreas/git/packages/apache2/.git/git-ubuntu-cache/apache2_2.4.33.orig.tar.bz2
05/09/2018 16:39:09 - DEBUG:Executing: sh -c "dpkg-parsechangelog -l- -SDistribution"
05/09/2018 16:39:09 - DEBUG:Caching dsc file
Traceback (most recent call last):
  File "/snap/git-ubuntu/427/bin/git-ubuntu", line 11, in <module>
    load_entry_point('gitubuntu==0.7.4', 'console_scripts', 'git-ubuntu')()
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/__main__.py", line 243, in main
    sys.exit(args.func(args))
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/buildsource.py", line 103, in cli_main
    default_rem_args=default_rem_args,
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 708, in cli_main
    retry_backoffs=args.retry_backoffs,
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 494, in main
    retry_backoffs,
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 1204, in fetch_orig_and_build
    tarballs = entry.mechanism(changelog, entry.source)
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 387, in fetch_orig_from_launchpad
    _symlink_paths_into_parent_dir(cached_paths)
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 208, in _symlink_paths_into_parent_dir
    new_path = _symlink_into_parent_dir(path)
  File "/snap/git-ubuntu/427/lib/python3.6/site-packages/gitubuntu/build.py", line 151, in _symlink_into_parent_dir
    raise FileExistsError('File exists %s' % destination_path)
FileExistsError: File exists ../apache2_2.4.33.orig.tar.bz2

Maybe related, but the orig tarball contains two empty directories:
httpd-2.4.33/docs/manual/style/lang
httpd-2.4.33/docs/manual/style/xsl/util