[INFO] cloning repository https://github.com/truongtu2111/return_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/truongtu2111/return_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftruongtu2111%2Freturn_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftruongtu2111%2Freturn_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c740a43c753605ef8ba66d02233dd26b6d78c2ed
[INFO] documenting truongtu2111/return_rust against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftruongtu2111%2Freturn_rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/truongtu2111/return_rust on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/truongtu2111/return_rust
[INFO] finished tweaking git repo https://github.com/truongtu2111/return_rust
[INFO] tweaked toml for git repo https://github.com/truongtu2111/return_rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/truongtu2111/return_rust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1f3db7ebac02196f37d127e1984bf51805196e37e9d8d90d4a3222753dae3dfd
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "1f3db7ebac02196f37d127e1984bf51805196e37e9d8d90d4a3222753dae3dfd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1f3db7ebac02196f37d127e1984bf51805196e37e9d8d90d4a3222753dae3dfd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1f3db7ebac02196f37d127e1984bf51805196e37e9d8d90d4a3222753dae3dfd", kill_on_drop: false }`
[INFO] [stdout] 1f3db7ebac02196f37d127e1984bf51805196e37e9d8d90d4a3222753dae3dfd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 77d033b099c7d86a2542b3563cd8c31048f9608893102c356ef7e46c55005d5e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "77d033b099c7d86a2542b3563cd8c31048f9608893102c356ef7e46c55005d5e", kill_on_drop: false }`
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]  Documenting return_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 4.12s
[INFO] running `Command { std: "docker" "inspect" "77d033b099c7d86a2542b3563cd8c31048f9608893102c356ef7e46c55005d5e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "77d033b099c7d86a2542b3563cd8c31048f9608893102c356ef7e46c55005d5e", kill_on_drop: false }`
[INFO] [stdout] 77d033b099c7d86a2542b3563cd8c31048f9608893102c356ef7e46c55005d5e