[INFO] cloning repository https://github.com/fenhl/adventofcode-2015-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/fenhl/adventofcode-2015-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffenhl%2Fadventofcode-2015-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffenhl%2Fadventofcode-2015-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] eabb127d7f02d1a1e8985e3240435dc29cfc121f
[INFO] building fenhl/adventofcode-2015-rust against master#44f415c1d617ebc7b931a243b7b321ef8a6ca47c for pr-142134-abi-ast-error
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffenhl%2Fadventofcode-2015-rust" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] error: failed to write new configuration file /workspace/builds/worker-7-tc1/source/.git/config.lock
[INFO] [stderr] fatal: could not set 'core.filemode' to 'true'


failed to checkout https://github.com/fenhl/adventofcode-2015-rust

Caused by:
    command failed: exit status: 128