[INFO] cloning repository https://github.com/songhaoxin/simple-tcp-echo-server
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/songhaoxin/simple-tcp-echo-server" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsonghaoxin%2Fsimple-tcp-echo-server", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsonghaoxin%2Fsimple-tcp-echo-server'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f1f95008231cdf69608ac51b88d18e0d37d91a35
[INFO] checking songhaoxin/simple-tcp-echo-server against master#aa067fb984d36462548bb785da221bfaf38253f0 for pr-122470
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsonghaoxin%2Fsimple-tcp-echo-server" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/songhaoxin/simple-tcp-echo-server on toolchain aa067fb984d36462548bb785da221bfaf38253f0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+aa067fb984d36462548bb785da221bfaf38253f0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/songhaoxin/simple-tcp-echo-server
[INFO] finished tweaking git repo https://github.com/songhaoxin/simple-tcp-echo-server
[INFO] tweaked toml for git repo https://github.com/songhaoxin/simple-tcp-echo-server written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/songhaoxin/simple-tcp-echo-server 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" "+aa067fb984d36462548bb785da221bfaf38253f0" "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 songhaoxin/simple-tcp-echo-server against try#707d6562f55b55a7aab4ab3a904997116b358314 for pr-122470
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsonghaoxin%2Fsimple-tcp-echo-server" "/workspace/builds/worker-2-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/songhaoxin/simple-tcp-echo-server on toolchain 707d6562f55b55a7aab4ab3a904997116b358314
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/songhaoxin/simple-tcp-echo-server
[INFO] finished tweaking git repo https://github.com/songhaoxin/simple-tcp-echo-server
[INFO] tweaked toml for git repo https://github.com/songhaoxin/simple-tcp-echo-server written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/songhaoxin/simple-tcp-echo-server 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" "+707d6562f55b55a7aab4ab3a904997116b358314" "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-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+707d6562f55b55a7aab4ab3a904997116b358314" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7252d395b6347a9737129d78d41d2f4bf2f86cb1f092c2c57a1289b1d3209d69
[INFO] running `Command { std: "docker" "start" "-a" "7252d395b6347a9737129d78d41d2f4bf2f86cb1f092c2c57a1289b1d3209d69", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7252d395b6347a9737129d78d41d2f4bf2f86cb1f092c2c57a1289b1d3209d69", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7252d395b6347a9737129d78d41d2f4bf2f86cb1f092c2c57a1289b1d3209d69", kill_on_drop: false }`
[INFO] [stdout] 7252d395b6347a9737129d78d41d2f4bf2f86cb1f092c2c57a1289b1d3209d69
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "+707d6562f55b55a7aab4ab3a904997116b358314" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2dfa4661b3ec6392378b9ecabbc0a56d848952a7fc35bc5c6ee5e9dfc4dc3128
[INFO] running `Command { std: "docker" "start" "-a" "2dfa4661b3ec6392378b9ecabbc0a56d848952a7fc35bc5c6ee5e9dfc4dc3128", kill_on_drop: false }`
[INFO] [stderr]     Checking tcp-echo-server v0.1.0 (/opt/rustwide/workdir/tcp-echo-server)
[INFO] [stderr]     Checking tcp-echo-client v0.1.0 (/opt/rustwide/workdir/tcp-echo-client)
[INFO] [stdout] warning: the item `Write` is imported redundantly
[INFO] [stdout]  --> tcp-echo-client/src/main.rs:1:44
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::{self, prelude::*, BufReader, Write};
[INFO] [stdout]   |                     ----------             ^^^^^
[INFO] [stdout]   |                     |
[INFO] [stdout]   |                     the item `Write` is already imported here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Write` is imported redundantly
[INFO] [stdout]  --> tcp-echo-client/src/main.rs:1:44
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::io::{self, prelude::*, BufReader, Write};
[INFO] [stdout]   |                     ----------             ^^^^^
[INFO] [stdout]   |                     |
[INFO] [stdout]   |                     the item `Write` is already imported here
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> tcp-echo-client/src/main.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | /     loop {
[INFO] [stdout] 8  | |         let mut input = String::new();
[INFO] [stdout] 9  | |         io::stdin()
[INFO] [stdout] 10 | |             .read_line(&mut input)
[INFO] [stdout] ...  |
[INFO] [stdout] 23 | |         println!("");
[INFO] [stdout] 24 | |     }
[INFO] [stdout]    | |_____- any code following this expression is unreachable
[INFO] [stdout] 25 |       Ok(())
[INFO] [stdout]    |       ^^^^^^ unreachable expression
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> tcp-echo-client/src/main.rs:25:5
[INFO] [stdout]    |
[INFO] [stdout] 7  | /     loop {
[INFO] [stdout] 8  | |         let mut input = String::new();
[INFO] [stdout] 9  | |         io::stdin()
[INFO] [stdout] 10 | |             .read_line(&mut input)
[INFO] [stdout] ...  |
[INFO] [stdout] 23 | |         println!("");
[INFO] [stdout] 24 | |     }
[INFO] [stdout]    | |_____- any code following this expression is unreachable
[INFO] [stdout] 25 |       Ok(())
[INFO] [stdout]    |       ^^^^^^ unreachable expression
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.04s
[INFO] running `Command { std: "docker" "inspect" "2dfa4661b3ec6392378b9ecabbc0a56d848952a7fc35bc5c6ee5e9dfc4dc3128", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2dfa4661b3ec6392378b9ecabbc0a56d848952a7fc35bc5c6ee5e9dfc4dc3128", kill_on_drop: false }`
[INFO] [stdout] 2dfa4661b3ec6392378b9ecabbc0a56d848952a7fc35bc5c6ee5e9dfc4dc3128