From http://o/e/m24cf356c88000018

The cq-v8 log at 2016-12-14 07:08:20 has the following (read from bottom to top):

07:08:20.322
[pid:17778 tid:140209394894592 errors:171] Transient error: Unable to get commit position from footers File "/usr/lib/python2.7/threading.py", line 783, in __bootstrap self.__bootstrap_inner() File "/usr/lib/python2.7/threading.py", line 810, in __bootstrap_inner self.run() File "/usr/lib/python2.7/threading.py", line 763, in run self.__target(*self.__args, **self.__kwargs) File "/b/infra_internal/commit_queue/pending_manager/base.py", line 334, in _commit self._commit_patch(pending) File "/b/infra_internal/commit_queue/pending_manager/rietveld.py", line 463, in _commit_patch self._commit_to_checkout(pending) File "/b/infra_internal/commit_queue/pending_manager/rietveld.py", line 418, in _commit_to_checkout pre_push_cb=lambda cr, pr: pending._publish_intent_to_push( File "/b/infra_internal/commit_queue/checkouts.py", line 591, in amend_and_push original_description, target_remote_ref) File "/b/infra_internal/commit_queue/checkouts.py", line 532, in _add_git_number description, parent_rev, parent_msg, target_remote_ref) File "/b/infra_internal/commit_queue/errors.py", line 210, in wrapper return func(obj, *args, **kwargs), None File "/usr/lib/python2.7/contextlib.py", line 35, in __exit__ self.gen.throw(type, value, traceback) File "/b/infra_internal/commit_queue/errors.py", line 169, in track_exceptions self.stacktrace = (''.join(traceback.format_stack()) + Traceback (most recent call last): File "/b/infra_internal/commit_queue/errors.py", line 166, in track_exceptions yield ctx File "/b/infra_internal/commit_queue/errors.py", line 210, in wrapper return func(obj, *args, **kwargs), None File "/b/infra_internal/commit_queue/checkouts.py", line 498, in _add_git_number_footers parent_rev, parent_msg, target_remote_ref) File "/b/infra_internal/commit_queue/utils/git_cl.py", line 169, in update_with_git_number_footers parent_position = git_footers.get_position(parent_footer_map) File "/b/infra_internal/commit_queue/utils/git_footers.py", line 143, in get_position raise ValueError('Unable to get commit position from footers') ValueError: Unable to get commit position from footers
07:08:20.298
[pid:17778 tid:140209394894592 checkouts:495] adding git number with parent u'7a7781c6413c30bbe96766719bc5b011bf49107d' msg('git cl commit.\n\nBUG=\n\nReview-Url: https://codereview.chromium.org/2564433005 .\nCr-Commit-Position: refs/heads/gnumb-test/cq@{#2}\nCr-Branched-From: 5c49df2da689e4374ea073a89714b4597283d138-refs/heads/master@{#41618}\n\n') destined for refs/heads/gnumb-test/cq
07:08:20.275
[pid:17778 tid:140209394894592 utils.subprocess2:207] git show -s --format=%B HEAD~1; cwd=/b/infra_internal/commit_queue/workdir/v8
07:08:20.261
[pid:17778 tid:140209394894592 utils.subprocess2:207] git rev-parse HEAD~1; cwd=/b/infra_internal/commit_queue/workdir/v8
07:08:20.259
[pid:17778 tid:140209394894592 checkouts:516] generating git numberer footers in commit for refs/heads/gnumb-test/cq

It looks like it tries to add a Cr-Commit-Position footer (the "generating git numberer footers" log line) but then can't find it again later.

tandrii: can you investigate why this fails?  If it fails to add the footer to the CL, why is no error reported?  If not, why's it failing to find it again?