[INFO] cloning repository https://github.com/xiao137/rcli
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/xiao137/rcli" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxiao137%2Frcli", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxiao137%2Frcli'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ae1cebc8b955a00c7d975aefcd9d7ec4dbafc240
[INFO] checking xiao137/rcli against master#75530e9f72a1990ed2305e16fd51d02f47048f12 for pr-135899
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fxiao137%2Frcli" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update ref 'refs/heads/master': couldn't write '/workspace/builds/worker-6-tc1/source/.git/refs/heads/master.lock'


failed to checkout https://github.com/xiao137/rcli

Caused by:
    command failed: exit status: 128