[INFO] cloning repository https://github.com/andrecacio/threadpool
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/andrecacio/threadpool" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandrecacio%2Fthreadpool", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandrecacio%2Fthreadpool'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 49f87907c13de46ec8758dbc20d5c9ed6530ac54
[INFO] checking andrecacio/threadpool against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fandrecacio%2Fthreadpool" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/andrecacio/threadpool
[INFO] finished tweaking git repo https://github.com/andrecacio/threadpool
[INFO] tweaked toml for git repo https://github.com/andrecacio/threadpool written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/andrecacio/threadpool on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/andrecacio/threadpool 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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5eda51fdd09c2e4ca12f483686fc4d13e9ae1d93f9d087634ae0f17c9dbfbea7
[INFO] running `Command { std: "docker" "start" "-a" "5eda51fdd09c2e4ca12f483686fc4d13e9ae1d93f9d087634ae0f17c9dbfbea7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5eda51fdd09c2e4ca12f483686fc4d13e9ae1d93f9d087634ae0f17c9dbfbea7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5eda51fdd09c2e4ca12f483686fc4d13e9ae1d93f9d087634ae0f17c9dbfbea7", kill_on_drop: false }`
[INFO] [stdout] 5eda51fdd09c2e4ca12f483686fc4d13e9ae1d93f9d087634ae0f17c9dbfbea7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7620694e7b77085e2d3f2002d516f0dc013ddaa08bc9692e4d1debb822f90d73
[INFO] running `Command { std: "docker" "start" "-a" "7620694e7b77085e2d3f2002d516f0dc013ddaa08bc9692e4d1debb822f90d73", kill_on_drop: false }`
[INFO] [stderr]     Checking threadpool v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::sync::mpsc::Receiver`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::sync::mpsc::Receiver;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::sync::mpsc::Receiver`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::sync::mpsc::Receiver;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:82:8
[INFO] [stdout]    |
[INFO] [stdout] 82 |    let mut pool = ThreadPool::new(2);
[INFO] [stdout]    |        ----^^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:82:8
[INFO] [stdout]    |
[INFO] [stdout] 82 |    let mut pool = ThreadPool::new(2);
[INFO] [stdout]    |        ----^^^^
[INFO] [stdout]    |        |
[INFO] [stdout]    |        help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `workers` is never read
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct ThreadPool{
[INFO] [stdout]   |        ---------- field in this struct
[INFO] [stdout] 8 |     workers: Vec<Worker>,
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `id` and `handle` are never read
[INFO] [stdout]   --> src/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 12 | struct Worker{
[INFO] [stdout]    |        ------ fields in this struct
[INFO] [stdout] 13 |     id: usize,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 14 |     handle: Option<JoinHandle<()>>,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `workers` is never read
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | struct ThreadPool{
[INFO] [stdout]   |        ---------- field in this struct
[INFO] [stdout] 8 |     workers: Vec<Worker>,
[INFO] [stdout]   |     ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `id` and `handle` are never read
[INFO] [stdout]   --> src/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 12 | struct Worker{
[INFO] [stdout]    |        ------ fields in this struct
[INFO] [stdout] 13 |     id: usize,
[INFO] [stdout]    |     ^^
[INFO] [stdout] 14 |     handle: Option<JoinHandle<()>>,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.10s
[INFO] running `Command { std: "docker" "inspect" "7620694e7b77085e2d3f2002d516f0dc013ddaa08bc9692e4d1debb822f90d73", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7620694e7b77085e2d3f2002d516f0dc013ddaa08bc9692e4d1debb822f90d73", kill_on_drop: false }`
[INFO] [stdout] 7620694e7b77085e2d3f2002d516f0dc013ddaa08bc9692e4d1debb822f90d73