[INFO] cloning repository https://github.com/levelboy/rustlings
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/levelboy/rustlings" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flevelboy%2Frustlings", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flevelboy%2Frustlings'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bcbc8fadb984b27776fbd4ef76187c3e7c4ba0a2
[INFO] checking levelboy/rustlings against master#4fa76a4a7742bb9c1febe33019f5a9e7e4839a65 for pr-83744
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flevelboy%2Frustlings" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/levelboy/rustlings on toolchain 4fa76a4a7742bb9c1febe33019f5a9e7e4839a65
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/levelboy/rustlings
[INFO] finished tweaking git repo https://github.com/levelboy/rustlings
[INFO] tweaked toml for git repo https://github.com/levelboy/rustlings written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/levelboy/rustlings already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4e0d74b484905067b8e4876403b798cdad6b10bab1576284de60c322e0c85fdc
[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" "4e0d74b484905067b8e4876403b798cdad6b10bab1576284de60c322e0c85fdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4e0d74b484905067b8e4876403b798cdad6b10bab1576284de60c322e0c85fdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e0d74b484905067b8e4876403b798cdad6b10bab1576284de60c322e0c85fdc", kill_on_drop: false }`
[INFO] [stdout] 4e0d74b484905067b8e4876403b798cdad6b10bab1576284de60c322e0c85fdc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "RUSTFLAGS=--cap-lints=forbid" "-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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+4fa76a4a7742bb9c1febe33019f5a9e7e4839a65" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] acad5f05e119c0d8628825d43121c4e4cfcb1e75a5839fbdd19834aa2f183206
[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" "acad5f05e119c0d8628825d43121c4e4cfcb1e75a5839fbdd19834aa2f183206", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.34
[INFO] [stderr]    Compiling serde v1.0.92
[INFO] [stderr]     Checking lazycell v1.2.1
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking glob v0.3.0
[INFO] [stderr]     Checking log v0.4.6
[INFO] [stderr]    Compiling quote v0.6.12
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking iovec v0.1.2
[INFO] [stderr]     Checking clicolors-control v1.0.0
[INFO] [stderr]     Checking inotify-sys v0.1.3
[INFO] [stderr]     Checking filetime v0.2.5
[INFO] [stderr]     Checking regex v1.1.6
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking float-cmp v0.4.0
[INFO] [stderr]     Checking inotify v0.7.0
[INFO] [stderr]     Checking parking_lot_core v0.5.0
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking parking_lot v0.8.0
[INFO] [stderr]     Checking console v0.8.0
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking predicates v1.0.1
[INFO] [stderr]     Checking mio-extras v2.0.5
[INFO] [stderr]     Checking indicatif v0.10.3
[INFO] [stderr]     Checking notify v4.0.15
[INFO] [stderr]    Compiling serde_derive v1.0.92
[INFO] [stderr]     Checking serde_json v1.0.39
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking rustlings v4.2.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 42.60s
[INFO] running `Command { std: "docker" "inspect" "acad5f05e119c0d8628825d43121c4e4cfcb1e75a5839fbdd19834aa2f183206", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "acad5f05e119c0d8628825d43121c4e4cfcb1e75a5839fbdd19834aa2f183206", kill_on_drop: false }`
[INFO] [stdout] acad5f05e119c0d8628825d43121c4e4cfcb1e75a5839fbdd19834aa2f183206