[INFO] cloning repository https://github.com/woodgear/rust-channel-benchmark
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/woodgear/rust-channel-benchmark" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwoodgear%2Frust-channel-benchmark", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwoodgear%2Frust-channel-benchmark'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1572d9045ed90d8709bb1431b8c5e539bfcdf004
[INFO] checking woodgear/rust-channel-benchmark against try#f6e2f78768c57172b99c3e85892f867894dc7e30 for pr-75502
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwoodgear%2Frust-channel-benchmark" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/woodgear/rust-channel-benchmark on toolchain f6e2f78768c57172b99c3e85892f867894dc7e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/woodgear/rust-channel-benchmark
[INFO] finished tweaking git repo https://github.com/woodgear/rust-channel-benchmark
[INFO] tweaked toml for git repo https://github.com/woodgear/rust-channel-benchmark written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/woodgear/rust-channel-benchmark already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] e88b01c02174994320cfeafb94c9c5d893d0e5e2c98202c1b0e191283a0e55ee
[INFO] running `Command { std: "docker" "start" "-a" "e88b01c02174994320cfeafb94c9c5d893d0e5e2c98202c1b0e191283a0e55ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e88b01c02174994320cfeafb94c9c5d893d0e5e2c98202c1b0e191283a0e55ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e88b01c02174994320cfeafb94c9c5d893d0e5e2c98202c1b0e191283a0e55ee", kill_on_drop: false }`
[INFO] [stdout] e88b01c02174994320cfeafb94c9c5d893d0e5e2c98202c1b0e191283a0e55ee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d5e3058323373fa633f9c9ec67d89f0315ff544d77031b8bac85f5b735452c59
[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" "d5e3058323373fa633f9c9ec67d89f0315ff544d77031b8bac85f5b735452c59", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling ryu v1.0.2
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking itoa v0.4.4
[INFO] [stderr]    Compiling crossbeam-utils v0.7.0
[INFO] [stderr]     Checking serde_json v1.0.44
[INFO] [stderr]     Checking crossbeam-channel v0.4.0
[INFO] [stderr]     Checking channel-benchmark v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:26:21
[INFO] [stdout]    |
[INFO] [stdout] 26 |                 for i in 0..items_count {
[INFO] [stdout]    |                     ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `sender_thread_pool`
[INFO] [stdout]   --> src/main.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let sender_thread_pool: Vec<JoinHandle<()>> = (0..sender_count)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_sender_thread_pool`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:26:21
[INFO] [stdout]    |
[INFO] [stdout] 26 |                 for i in 0..items_count {
[INFO] [stdout]    |                     ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `sender_thread_pool`
[INFO] [stdout]   --> src/main.rs:21:9
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let sender_thread_pool: Vec<JoinHandle<()>> = (0..sender_count)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_sender_thread_pool`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:21
[INFO] [stdout]    |
[INFO] [stdout] 28 |                     s.send(msg);
[INFO] [stdout]    |                     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:21
[INFO] [stdout]    |
[INFO] [stdout] 28 |                     s.send(msg);
[INFO] [stdout]    |                     ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/main.rs:131:5
[INFO] [stdout]     |
[INFO] [stdout] 131 |     std::fs::write(path, js.to_string().as_bytes());
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]    --> src/main.rs:131:5
[INFO] [stdout]     |
[INFO] [stdout] 131 |     std::fs::write(path, js.to_string().as_bytes());
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.20s
[INFO] running `Command { std: "docker" "inspect" "d5e3058323373fa633f9c9ec67d89f0315ff544d77031b8bac85f5b735452c59", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d5e3058323373fa633f9c9ec67d89f0315ff544d77031b8bac85f5b735452c59", kill_on_drop: false }`
[INFO] [stdout] d5e3058323373fa633f9c9ec67d89f0315ff544d77031b8bac85f5b735452c59