https://uberchromegw.corp.google.com/i/chromeos/builders/master-paladin/builds/15723
https://uberchromegw.corp.google.com/i/chromeos/builders/master-paladin/builds/15722
https://uberchromegw.corp.google.com/i/chromeos/builders/master-paladin/builds/15721

18:17:03: INFO: RunCommand: /b/c/cbuild/repository/chromite/bin/cros_mark_as_stable '--srcroot=/b/c/cbuild/repository/src' '--overlays=...


cros_mark_as_stable: Unhandled exception:
Traceback (most recent call last):
  File "/b/c/cbuild/repository/chromite/bin/cros_mark_as_stable", line 168, in <module>
    DoMain()
  File "/b/c/cbuild/repository/chromite/bin/cros_mark_as_stable", line 164, in DoMain
    commandline.ScriptWrapperMain(FindTarget)
  File "/b/c/cbuild/repository/chromite/lib/commandline.py", line 860, in ScriptWrapperMain
    ret = target(argv[1:])
  File "/b/c/cbuild/repository/chromite/scripts/cros_mark_as_stable.py", line 291, in main
    staging_branch=options.staging_branch)
  File "/b/c/cbuild/repository/chromite/scripts/cros_mark_as_stable.py", line 139, in PushChange
    bad_cls = git.RunGit(cwd, bad_cl_cmd).output
  File "/b/c/cbuild/repository/chromite/lib/git.py", line 820, in RunGit
    ['git'] + cmd, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 243, in GenericRetry
    return _run()
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 176, in _Wrapper
    ret = func(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/retry_util.py", line 242, in _run
    return functor(*args, **kwargs)
  File "/b/c/cbuild/repository/chromite/lib/cros_build_lib.py", line 645, in RunCommand
    raise RunCommandError(msg, cmd_result)
chromite.lib.cros_build_lib.RunCommandError: return code: 128; command: git log '--format=short' --perl-regexp --author '^(?!chrome-bot)' refs/remotes/cros/master..stabilizing_branch
fatal: cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE
cmd=['git', 'log', '--format=short', '--perl-regexp', '--author', '^(?!chrome-bot)', u'refs/remotes/cros/master..stabilizing_branch'], cwd=/b/c/cbuild/repository/src/overlays/overlay-variant-auron-paine
18:17:05: ERROR: