The error is: 09:16:47 WARNING - fetch-content script not found, downloading manually 09:16:47 INFO - mkdir: /builds/worker/fetches 09:16:47 ERROR - Can't create directory /builds/worker/fetches! 09:16:47 INFO - Downloading https://queue.taskcluster.net/v1/task/Os44oAP8SyOFWXQNxHupHA/artifacts/public/build/grcov.tar.xz to /builds/worker/fetches/grcov.tar.xz 09:16:47 INFO - retry: Calling _download_file with args: (), kwargs: {'url': 'https://queue.taskcluster.net/v1/task/Os44oAP8SyOFWXQNxHupHA/artifacts/public/build/grcov.tar.xz', 'file_name': '/builds/worker/fetches/grcov.tar.xz'}, attempt #1 09:16:48 ERROR - Exception during post-action for download-and-extract: Traceback (most recent call last): 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/base/script.py", line 2040, in run_action 09:16:48 ERROR - method(action, success=success and self.return_code == 0) 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/mozilla/testing/codecoverage.py", line 156, in setup_coverage_tools 09:16:48 ERROR - self.fetch_content() 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/mozilla/fetches.py", line 37, in fetch_content 09:16:48 ERROR - self._download_fetches() 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/mozilla/fetches.py", line 58, in _download_fetches 09:16:48 ERROR - path = self.download_file(url, parent_dir=extdir) 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/base/script.py", line 794, in download_file 09:16:48 ERROR - retry_config=retry_config 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/base/script.py", line 584, in _retry_download 09:16:48 ERROR - **retry_args 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/base/script.py", line 1160, in retry 09:16:48 ERROR - status = action(*args, **kwargs) 09:16:48 ERROR - File "/Users/cltbld/tasks/task_1541175354/mozharness/mozharness/base/script.py", line 498, in _download_file 09:16:48 ERROR - local_file = open(file_name, 'wb') 09:16:48 ERROR - IOError: [Errno 2] No such file or directory: '/builds/worker/fetches/grcov.tar.xz' 09:16:48 INFO - [mozharness: 2018-11-02 16:16:48.534200Z] Finished download-and-extract step (success) 09:16:48 FATAL - Aborting due to failure in post-action listener. 09:16:48 FATAL - Running post_fatal callback... 09:16:48 FATAL - Exiting -1 Probably we don't have permissions to create /builds/worker/fetches?

Hm, yeah this might be the first attempt at getting an OSX based task to use fetches. Maybe we run as root on Linux but not OSX or something like that. Could you change MOZ_FETCHES_DIR in the task definition to point to a location that is writeable? Otherwise it looks like you might be able to create a "Writeable Directory Cache" mount at /builds/worker/fetches: https://docs.taskcluster.net/docs/reference/workers/generic-worker/docs/payload Though I've never used that myself, so maybe the taskcluster team can help out if it doesn't do what it sounds like.

(In reply to Andrew Halberstadt [:ahal] from comment #2) > Hm, yeah this might be the first attempt at getting an OSX based task to use > fetches. Maybe we run as root on Linux but not OSX or something like that. > Could you change MOZ_FETCHES_DIR in the task definition to point to a > location that is writeable? To test this out you can just use the task-creator and change the env there.

Pushed by mcastelluccio@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/ee46d9630aa0 Use a relative directory for MOZ_FETCHES_DIR on Mac too. r=ahal