[INFO] cloning repository https://github.com/justtails/rust-learn
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/justtails/rust-learn" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 838909316d26ebd96323569dd04867fe2e28c0af
[INFO] testing justtails/rust-learn against try#b8e88e5ddf5521a9f43ee3f62a702388c713e4bb for pr-155114
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update the ref 'refs/heads/master': unable to create directory for '/workspace/builds/worker-6-tc2/source/.git/logs/refs/heads/master': No such file or directory
[INFO] testing justtails/rust-learn against try#b8e88e5ddf5521a9f43ee3f62a702388c713e4bb for pr-155114
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update the ref 'refs/heads/master': unable to create directory for '/workspace/builds/worker-6-tc2/source/.git/logs/refs/heads/master': No such file or directory
[INFO] testing justtails/rust-learn against try#b8e88e5ddf5521a9f43ee3f62a702388c713e4bb for pr-155114
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update the ref 'refs/heads/master': unable to create directory for '/workspace/builds/worker-6-tc2/source/.git/logs/refs/heads/master': No such file or directory
[INFO] testing justtails/rust-learn against try#b8e88e5ddf5521a9f43ee3f62a702388c713e4bb for pr-155114
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update the ref 'refs/heads/master': unable to create directory for '/workspace/builds/worker-6-tc2/source/.git/logs/refs/heads/master': No such file or directory
[INFO] testing justtails/rust-learn against try#b8e88e5ddf5521a9f43ee3f62a702388c713e4bb for pr-155114
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjusttails%2Frust-learn" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] [stderr] fatal: update_ref failed for ref 'HEAD': cannot update the ref 'refs/heads/master': unable to create directory for '/workspace/builds/worker-6-tc2/source/.git/logs/refs/heads/master': No such file or directory


overridden task result to prepare-fail:unknown

Caused by:
    0: uncategorized prepare error
    1: failed to checkout https://github.com/justtails/rust-learn
    2: command failed: exit status: 128
       
       