[INFO] updating cached repository https://github.com/rust-lang-nursery/chalk
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] [stderr] From https://github.com/rust-lang-nursery/chalk
[INFO] [stderr]  + c307dcb20...fc898d3d7 gh-pages   -> gh-pages  (forced update)
[INFO] [stderr]    ecf05d995..656be2d35  master     -> master
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 656be2d35d18a2adc5b3984608d2fbe9cef6e947
[ERROR] this task or one of its parent failed!
[ERROR] command `"/workspace/cargo-home/bin/cargo" "+74e80468347471779be6060d8d7d6d04e98e467f" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.