Error when using the python plugin and libc6-dev as stage package

[Leo Arias]

I'm trying to snap rainbowstream [1]. It uses the python plugin and requires libc6-dev as a stage package, but that fails to snap with this error:

[Errno 1] Operation not permitted: '/tmp/test/parts/my-part/install/usr/lib/x86_64-linux-gnu/libutil.so'

To reproduce:

$ snapcraft init
edit the snapcraft.yaml: change the plugin to python, and add stage-packages: [libc6-dev]
$ snapcraft

[1] https://github.com/elopio/rainbowstream/tree/snapcraft

[Sergio Schvezov (sergiusens)]

Please run with --debug

[Leo Arias (elopio)]

Building rainbowstream
Collecting pip
  Using cached pip-8.1.2-py2.py3-none-any.whl
Collecting setuptools
  Using cached setuptools-28.0.0-py2.py3-none-any.whl
Collecting wheel
  Using cached wheel-0.29.0-py2.py3-none-any.whl
Installing collected packages: pip, setuptools, wheel
Successfully installed pip-8.1.2 setuptools-28.0.0 wheel-0.29.0
pip install --user --no-compile --disable-pip-version-check .
Processing /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/build
  Requirement already satisfied (use --upgrade to upgrade): rainbowstream==1.3.3 from file:///home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/build in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages
Requirement already satisfied (use --upgrade to upgrade): python-dateutil in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): arrow in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): requests==2.5.3 in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): pyfiglet in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): twitter in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): Pillow in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): PySocks in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from rainbowstream==1.3.3)
Requirement already satisfied (use --upgrade to upgrade): six>=1.5 in /home/elopio/workspace/DTVD/rainbowstream/parts/rainbowstream/install/lib/python3.5/site-packages (from python-dateutil->rainbowstream==1.3.3)
Traceback (most recent call last):
  File "/usr/bin/snapcraft", line 31, in <module>
    snapcraft.main.main()
  File "/usr/lib/python3/dist-packages/snapcraft/main.py", line 219, in main
    return run(args, project_options)
  File "/usr/lib/python3/dist-packages/snapcraft/main.py", line 275, in run
    lifecycle.snap(project_options, args['<directory>'], args['--output'])
  File "/usr/lib/python3/dist-packages/snapcraft/internal/lifecycle.py", line 275, in snap
    snap = execute('prime', project_options)
  File "/usr/lib/python3/dist-packages/snapcraft/internal/lifecycle.py", line 101, in execute
    _Executor(config, project_options).run(step, part_names)
  File "/usr/lib/python3/dist-packages/snapcraft/internal/lifecycle.py", line 149, in run
    self._run_step(step, part, part_names)
  File "/usr/lib/python3/dist-packages/snapcraft/internal/l...