[INFO] cloning repository https://github.com/felixmaker/ugdown
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/felixmaker/ugdown" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffelixmaker%2Fugdown", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffelixmaker%2Fugdown'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 00a5100250d87b5f5dc71c104476f3055c3fb584
[INFO] checking felixmaker/ugdown against master#75530e9f72a1990ed2305e16fd51d02f47048f12 for pr-135899
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffelixmaker%2Fugdown" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] error: failed to write new configuration file /workspace/builds/worker-3-tc1/source/.git/config.lock
[INFO] [stderr] fatal: could not set 'core.repositoryformatversion' to '0'


failed to checkout https://github.com/felixmaker/ugdown

Caused by:
    command failed: exit status: 128