Comment 1 for bug 1717089

This is related to the latest charm tools snap. I'm also seeing the same when trying to build charms:

[hloeung@dharkan nrpe-charm]$ charm build
build: Composing into /var/lib/snapd/void
build: Destination charm directory: /var/lib/snapd/void/trusty/void
build: Please add a `repo` key to your layer.yaml, with a url from which your layer can be cloned.
Traceback (most recent call last):
  File "/snap/charm/17/bin/charm-build", line 11, in <module>
    load_entry_point('charm-tools==2.1.2', 'console_scripts', 'charm-build')()
  File "/snap/charm/17/lib/python2.7/site-packages/charmtools/build/builder.py", line 679, in main
    build()
  File "/snap/charm/17/lib/python2.7/site-packages/charmtools/build/builder.py", line 522, in __call__
    self.generate()
  File "/snap/charm/17/lib/python2.7/site-packages/charmtools/build/builder.py", line 473, in generate
    layers = self.fetch()
  File "/snap/charm/17/lib/python2.7/site-packages/charmtools/build/builder.py", line 246, in fetch
    self.target_dir.makedirs_p()
  File "/snap/charm/17/lib/python2.7/site-packages/path.py", line 1222, in makedirs_p
    self.makedirs(mode)
  File "/snap/charm/17/lib/python2.7/site-packages/path.py", line 1215, in makedirs
    os.makedirs(self, mode)
  File "/snap/charm/17/usr/lib/python2.7/os.py", line 150, in makedirs
    makedirs(head, mode)
  File "/snap/charm/17/usr/lib/python2.7/os.py", line 157, in makedirs
    mkdir(name, mode)
OSError: [Errno 13] Permission denied: '/var/lib/snapd/void/trusty'