[INFO] cloning repository https://github.com/joeldudley/obamas_head
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/joeldudley/obamas_head" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoeldudley%2Fobamas_head", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoeldudley%2Fobamas_head'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9ba104a08f8b0e116ccc183fe3af3239731e15a0
[INFO] checking joeldudley/obamas_head against try#ddfd70ee3c3748e597b32f416b0d15a4f6e37685 for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoeldudley%2Fobamas_head" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/joeldudley/obamas_head on toolchain ddfd70ee3c3748e597b32f416b0d15a4f6e37685
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/joeldudley/obamas_head
[INFO] finished tweaking git repo https://github.com/joeldudley/obamas_head
[INFO] tweaked toml for git repo https://github.com/joeldudley/obamas_head written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/joeldudley/obamas_head already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6c05754597b2cb165d85f8301e4036d530dd0c5b61ff600203dcf919ba01490e
[INFO] running `Command { std: "docker" "start" "-a" "6c05754597b2cb165d85f8301e4036d530dd0c5b61ff600203dcf919ba01490e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6c05754597b2cb165d85f8301e4036d530dd0c5b61ff600203dcf919ba01490e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c05754597b2cb165d85f8301e4036d530dd0c5b61ff600203dcf919ba01490e", kill_on_drop: false }`
[INFO] [stdout] 6c05754597b2cb165d85f8301e4036d530dd0c5b61ff600203dcf919ba01490e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 401b6ccace5b8b44257cdb96ac6fca72924816d5102c9e65b99489656ea07a1d
[INFO] running `Command { std: "docker" "start" "-a" "401b6ccace5b8b44257cdb96ac6fca72924816d5102c9e65b99489656ea07a1d", kill_on_drop: false }`
[INFO] [stderr]     Checking bufstream v0.1.4
[INFO] [stderr]     Checking obamas_head v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `sender`
[INFO] [stdout]   --> src/main.rs:24:10
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let (sender, receiver): (Sender<bool>, Receiver<bool>) = mpsc::channel();
[INFO] [stdout]    |          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_sender`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `receiver`
[INFO] [stdout]   --> src/main.rs:38:52
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn handle_incoming_requests(listener: TcpListener, receiver: Receiver<bool>) {
[INFO] [stdout]    |                                                    ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_receiver`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `sender`
[INFO] [stdout]   --> src/main.rs:24:10
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let (sender, receiver): (Sender<bool>, Receiver<bool>) = mpsc::channel();
[INFO] [stdout]    |          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_sender`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `receiver`
[INFO] [stdout]   --> src/main.rs:38:52
[INFO] [stdout]    |
[INFO] [stdout] 38 | fn handle_incoming_requests(listener: TcpListener, receiver: Receiver<bool>) {
[INFO] [stdout]    |                                                    ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_receiver`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:5
[INFO] [stdout]    |
[INFO] [stdout] 28 |     listener_thread_handle.join();
[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: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:28:5
[INFO] [stdout]    |
[INFO] [stdout] 28 |     listener_thread_handle.join();
[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: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "401b6ccace5b8b44257cdb96ac6fca72924816d5102c9e65b99489656ea07a1d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "401b6ccace5b8b44257cdb96ac6fca72924816d5102c9e65b99489656ea07a1d", kill_on_drop: false }`
[INFO] [stdout] 401b6ccace5b8b44257cdb96ac6fca72924816d5102c9e65b99489656ea07a1d