[INFO] cloning repository https://github.com/Akelio-zhang/rustlings-solutions
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Akelio-zhang/rustlings-solutions" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAkelio-zhang%2Frustlings-solutions", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAkelio-zhang%2Frustlings-solutions'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ead6ed4addc450befb60ff694aa41985a3691776
[INFO] checking Akelio-zhang/rustlings-solutions against beta for pr-78714
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAkelio-zhang%2Frustlings-solutions" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Akelio-zhang/rustlings-solutions on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Akelio-zhang/rustlings-solutions
[INFO] finished tweaking git repo https://github.com/Akelio-zhang/rustlings-solutions
[INFO] tweaked toml for git repo https://github.com/Akelio-zhang/rustlings-solutions written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/Akelio-zhang/rustlings-solutions already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f0a6a845286527f44526977f53b2e1ee1e5b1187023cf4080b076e891e2f1331
[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" "f0a6a845286527f44526977f53b2e1ee1e5b1187023cf4080b076e891e2f1331", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f0a6a845286527f44526977f53b2e1ee1e5b1187023cf4080b076e891e2f1331", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f0a6a845286527f44526977f53b2e1ee1e5b1187023cf4080b076e891e2f1331", kill_on_drop: false }`
[INFO] [stdout] f0a6a845286527f44526977f53b2e1ee1e5b1187023cf4080b076e891e2f1331
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 23ab043b07d83f921c130db3a822a50a7d16dfc919c6439edb51088ee6d79caf
[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" "23ab043b07d83f921c130db3a822a50a7d16dfc919c6439edb51088ee6d79caf", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.34
[INFO] [stderr]    Compiling serde v1.0.92
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking normalize-line-endings v0.2.2
[INFO] [stderr]     Checking clicolors-control v1.0.0
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking iovec v0.1.2
[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 clap v2.33.0
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking float-cmp v0.4.0
[INFO] [stderr]     Checking parking_lot_core v0.5.0
[INFO] [stderr]     Checking inotify v0.7.0
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking parking_lot v0.8.0
[INFO] [stderr]     Checking mio-extras v2.0.5
[INFO] [stderr]     Checking notify v4.0.15
[INFO] [stderr]     Checking console v0.8.0
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking predicates v1.0.1
[INFO] [stderr]     Checking indicatif v0.10.3
[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 v4.0.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 31.77s
[INFO] running `Command { std: "docker" "inspect" "23ab043b07d83f921c130db3a822a50a7d16dfc919c6439edb51088ee6d79caf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "23ab043b07d83f921c130db3a822a50a7d16dfc919c6439edb51088ee6d79caf", kill_on_drop: false }`
[INFO] [stdout] 23ab043b07d83f921c130db3a822a50a7d16dfc919c6439edb51088ee6d79caf