As usual, this is almost impossible to reproduce. Interestingly in this case we have two stack traces, one of them is incomplete because it's overwritten by the status area, and the remainder is properly delivered through the logging mechanism: ``` fusermount: failed to access mountpoint /home/tristan/.cache/buildstream/build/apps-lightsoff-l4dzm2ki/scratch/_/mount: Permission denied Process Process-358:4: Traceback (most recent call last): File "/usr/lib/python3.5/multiprocessing/process.py", line 249, in _bootstrap self.run() File "/usr/lib/python3.5/multiprocessing/process.py", line 93, in run self._target(*self._args, **self._kwargs) File "/codethink/GNOME/buildstream/buildstream/_fuse/mount.py", line 187, in __run_fuse [00:01:20][44fe0704][build:apps/lightsoff.bst ] BUG gnome/apps-lightsoff/44fe0704-build.7666.log An unhandled exception occured: Traceback (most recent call last): File "/codethink/GNOME/buildstream/buildstream/_scheduler/job.py", line 265, in child_action result = self.action(element) File "/codethink/GNOME/buildstream/buildstream/_scheduler/buildqueue.py", line 34, in process element._assemble() File "/codethink/GNOME/buildstream/buildstream/element.py", line 1092, in _assemble self.stage(sandbox) File "/codethink/GNOME/buildstream/buildstream/buildelement.py", line 174, in stage dep.integrate(sandbox) File "/codethink/GNOME/buildstream/buildstream/element.py", line 484, in integrate exitcode = sandbox.run(['sh', '-e', '-c', cmd], 0, env=environment, cwd='/') File "/codethink/GNOME/buildstream/buildstream/sandbox/_sandboxbwrap.py", line 179, in run self.try_remove_device(device_path) File "/codethink/GNOME/buildstream/buildstream/sandbox/_sandboxbwrap.py", line 342, in try_remove_device os.unlink(device_path) OSError: [Errno 107] Transport endpoint is not connected: '/home/tristan/.cache/buildstream/build/apps-lightsoff-l4dzm2ki/scratch/_/mount/dev/full' ``` It looks like the first overwritten stack trace is not from the main process, but from the *fuse* subprocess.