[INFO] cloning repository https://github.com/jeffawang/bigmath
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jeffawang/bigmath" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjeffawang%2Fbigmath", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjeffawang%2Fbigmath'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dc5a2012c010ed431033e78f59af993792c0d23f
[INFO] checking jeffawang/bigmath against master#249cb84316401daf040832cdbb8a45e0f5ab6af8 for pr-138438
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjeffawang%2Fbigmath" "/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.bare' to 'false'


failed to checkout https://github.com/jeffawang/bigmath

Caused by:
    command failed: exit status: 128