[INFO] cloning repository https://github.com/scolton99/cs496-textbook-examples
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/scolton99/cs496-textbook-examples" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscolton99%2Fcs496-textbook-examples", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscolton99%2Fcs496-textbook-examples'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] e6f3c357ca2a193521b4c12cacb00734ea786f18
[INFO] checking scolton99/cs496-textbook-examples against master#65cd843ae06ad00123c131a431ed5304e4cd577a for pr-122077
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscolton99%2Fcs496-textbook-examples" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scolton99/cs496-textbook-examples on toolchain 65cd843ae06ad00123c131a431ed5304e4cd577a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+65cd843ae06ad00123c131a431ed5304e4cd577a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] finished tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] tweaked toml for git repo https://github.com/scolton99/cs496-textbook-examples written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/scolton99/cs496-textbook-examples already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+65cd843ae06ad00123c131a431ed5304e4cd577a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[ERROR] this task or one of its parent failed!
[ERROR] no output for 300 seconds
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.
[INFO] checking scolton99/cs496-textbook-examples against try#e34498b580c936a8f8a419616d9571f03b6c038e for pr-122077
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscolton99%2Fcs496-textbook-examples" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scolton99/cs496-textbook-examples on toolchain e34498b580c936a8f8a419616d9571f03b6c038e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] finished tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] tweaked toml for git repo https://github.com/scolton99/cs496-textbook-examples written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/scolton99/cs496-textbook-examples already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "fetch" "--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
[ERROR] error running command: no output for 300 seconds
[INFO] checking scolton99/cs496-textbook-examples against try#e34498b580c936a8f8a419616d9571f03b6c038e for pr-122077
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fscolton99%2Fcs496-textbook-examples" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/scolton99/cs496-textbook-examples on toolchain e34498b580c936a8f8a419616d9571f03b6c038e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] finished tweaking git repo https://github.com/scolton99/cs496-textbook-examples
[INFO] tweaked toml for git repo https://github.com/scolton99/cs496-textbook-examples written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/scolton99/cs496-textbook-examples already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "fetch" "--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-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a83c86211192e879f8fc499c3d7bdb7a5da0ba8aae4b97f265d14875efaf7769
[INFO] running `Command { std: "docker" "start" "-a" "a83c86211192e879f8fc499c3d7bdb7a5da0ba8aae4b97f265d14875efaf7769", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a83c86211192e879f8fc499c3d7bdb7a5da0ba8aae4b97f265d14875efaf7769", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a83c86211192e879f8fc499c3d7bdb7a5da0ba8aae4b97f265d14875efaf7769", kill_on_drop: false }`
[INFO] [stdout] a83c86211192e879f8fc499c3d7bdb7a5da0ba8aae4b97f265d14875efaf7769
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+e34498b580c936a8f8a419616d9571f03b6c038e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 94bb8b1c65846d552c86eebf02e727531bbc1bb05446b3a8824606238c05f2a4
[INFO] running `Command { std: "docker" "start" "-a" "94bb8b1c65846d552c86eebf02e727531bbc1bb05446b3a8824606238c05f2a4", kill_on_drop: false }`
[INFO] [stderr]     Checking book-496 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/tcp.rs:2:15
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{Read, Write, BufReader, BufRead};
[INFO] [stdout]   |               ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/tcp.rs:2:15
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::io::{Read, Write, BufReader, BufRead};
[INFO] [stdout]   |               ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::net`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::net;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::net`
[INFO] [stdout]  --> src/main.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use std::net;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> src/main.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let x = Ipv4Addr::new(0, 0, 0, 0);
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> src/main.rs:9:9
[INFO] [stdout]   |
[INFO] [stdout] 9 |     let x = Ipv4Addr::new(0, 0, 0, 0);
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.13s
[INFO] running `Command { std: "docker" "inspect" "94bb8b1c65846d552c86eebf02e727531bbc1bb05446b3a8824606238c05f2a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "94bb8b1c65846d552c86eebf02e727531bbc1bb05446b3a8824606238c05f2a4", kill_on_drop: false }`
[INFO] [stdout] 94bb8b1c65846d552c86eebf02e727531bbc1bb05446b3a8824606238c05f2a4