[INFO] updating cached repository https://github.com/j127/rustlings-solutions
[INFO] running `Command { std: "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", kill_on_drop: false }`
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2ae0e2b32f7614ef9c51cf375e02c11c00fde7ff
[INFO] documenting j127/rustlings-solutions against master#394e1b40d264aa6928811919c1124fa248e7d802 for pr-73566
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj127%2Frustlings-solutions" "/workspace/builds/worker-11/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-11/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/j127/rustlings-solutions on toolchain 394e1b40d264aa6928811919c1124fa248e7d802
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/j127/rustlings-solutions
[INFO] finished tweaking git repo https://github.com/j127/rustlings-solutions
[INFO] tweaked toml for git repo https://github.com/j127/rustlings-solutions written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate git repo https://github.com/j127/rustlings-solutions already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1ff5e45b6aa7f2bc8fc3cf919b0c849d09258a81916a853e3b4b2065832ed3a7
[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" "1ff5e45b6aa7f2bc8fc3cf919b0c849d09258a81916a853e3b4b2065832ed3a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1ff5e45b6aa7f2bc8fc3cf919b0c849d09258a81916a853e3b4b2065832ed3a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ff5e45b6aa7f2bc8fc3cf919b0c849d09258a81916a853e3b4b2065832ed3a7", kill_on_drop: false }`
[INFO] [stdout] 1ff5e45b6aa7f2bc8fc3cf919b0c849d09258a81916a853e3b4b2065832ed3a7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env@sha256:819119df93c0f5eca3f29186f14981ef29945a311854d7222af07488600a2584" "/opt/rustwide/cargo-home/bin/cargo" "+394e1b40d264aa6928811919c1124fa248e7d802" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 520eb186f9b0862bff1d8fa42ef412ad836b088afc0f35c7655f74f3631df86a
[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" "520eb186f9b0862bff1d8fa42ef412ad836b088afc0f35c7655f74f3631df86a", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.34
[INFO] [stderr]     Checking smallvec v0.6.9
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]    Compiling num-traits v0.2.8
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking clicolors-control v1.0.0
[INFO] [stderr]     Checking inotify-sys v0.1.3
[INFO] [stderr]     Checking atty v0.2.11
[INFO] [stderr]     Checking filetime v0.2.5
[INFO] [stderr]     Checking rand_pcg v0.1.2
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]    Compiling parking_lot_core v0.5.0
[INFO] [stderr]    Compiling parking_lot v0.8.0
[INFO] [stderr]     Checking rand_chacha v0.1.1
[INFO] [stderr]     Checking inotify v0.7.0
[INFO] [stderr]     Checking console v0.8.0
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking mio-extras v2.0.5
[INFO] [stderr]     Checking notify v4.0.15
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking indicatif v0.10.3
[INFO] [stderr]    Compiling serde_derive v1.0.92
[INFO] [stderr]     Checking serde v1.0.92
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]  Documenting rustlings v2.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 48.51s
[INFO] running `Command { std: "docker" "inspect" "520eb186f9b0862bff1d8fa42ef412ad836b088afc0f35c7655f74f3631df86a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "520eb186f9b0862bff1d8fa42ef412ad836b088afc0f35c7655f74f3631df86a", kill_on_drop: false }`
[INFO] [stdout] 520eb186f9b0862bff1d8fa42ef412ad836b088afc0f35c7655f74f3631df86a