[INFO] cloning repository https://github.com/jw3/example-scala-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jw3/example-scala-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjw3%2Fexample-scala-rust", kill_on_drop: false }`
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[INFO] [stdout] c74216224bc4094d05e18b6811c6ebf34e3716ed
[INFO] checking jw3/example-scala-rust against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjw3%2Fexample-scala-rust" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jw3/example-scala-rust on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jw3/example-scala-rust
[INFO] finished tweaking git repo https://github.com/jw3/example-scala-rust
[INFO] tweaked toml for git repo https://github.com/jw3/example-scala-rust written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/jw3/example-scala-rust 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "inspect" "dbe4f8176ced5abc8ae28e3a88575156669385fd1abc48a1ee9bf16c136ee0ed", kill_on_drop: false }`
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[INFO] [stdout] dbe4f8176ced5abc8ae28e3a88575156669385fd1abc48a1ee9bf16c136ee0ed
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e09fbde39af0ec0a61b13fad1c49206861c2b5bc85fe8337fcc37706fa7f742e
[INFO] running `Command { std: "docker" "start" "-a" "e09fbde39af0ec0a61b13fad1c49206861c2b5bc85fe8337fcc37706fa7f742e", kill_on_drop: false }`
[INFO] [stderr]     Checking example-scala-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Receiver`, `Sender`
[INFO] [stdout]  --> src/main/rust/lib.rs:4:23
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::sync::mpsc::{Receiver, Sender};
[INFO] [stdout]   |                       ^^^^^^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]  --> src/main/rust/lib.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::sync::{mpsc, Arc, Mutex};
[INFO] [stdout]   |                       ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Receiver`, `Sender`
[INFO] [stdout]  --> src/main/rust/lib.rs:4:23
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::sync::mpsc::{Receiver, Sender};
[INFO] [stdout]   |                       ^^^^^^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]  --> src/main/rust/lib.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::sync::{mpsc, Arc, Mutex};
[INFO] [stdout]   |                       ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl B {
[INFO] [stdout]    | ------ associated function in this implementation
[INFO] [stdout] 22 |     fn new(cb: BSink) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `BSink` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:75:6
[INFO] [stdout]    |
[INFO] [stdout] 75 | type BSink = extern "C" fn(i64);
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main/rust/lib.rs:28:17
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 tx.send(i);
[INFO] [stdout]    |                 ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 let _ = tx.send(i);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: for loop over a `Result`. This is more readably written as an `if let` statement
[INFO] [stdout]   --> src/main/rust/lib.rs:34:22
[INFO] [stdout]    |
[INFO] [stdout] 34 |             for i in rx.recv() {
[INFO] [stdout]    |                      ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(for_loops_over_fallibles)]` on by default
[INFO] [stdout] help: to check pattern in a loop use `while let`
[INFO] [stdout]    |
[INFO] [stdout] 34 |             while let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~~~~ ~~~
[INFO] [stdout] help: consider using `if let` to clear intent
[INFO] [stdout]    |
[INFO] [stdout] 34 |             if let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~ ~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl B {
[INFO] [stdout]    | ------ associated function in this implementation
[INFO] [stdout] 22 |     fn new(cb: BSink) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `BSink` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:75:6
[INFO] [stdout]    |
[INFO] [stdout] 75 | type BSink = extern "C" fn(i64);
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main/rust/lib.rs:28:17
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 tx.send(i);
[INFO] [stdout]    |                 ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 let _ = tx.send(i);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: for loop over a `Result`. This is more readably written as an `if let` statement
[INFO] [stdout]   --> src/main/rust/lib.rs:34:22
[INFO] [stdout]    |
[INFO] [stdout] 34 |             for i in rx.recv() {
[INFO] [stdout]    |                      ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(for_loops_over_fallibles)]` on by default
[INFO] [stdout] help: to check pattern in a loop use `while let`
[INFO] [stdout]    |
[INFO] [stdout] 34 |             while let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~~~~ ~~~
[INFO] [stdout] help: consider using `if let` to clear intent
[INFO] [stdout]    |
[INFO] [stdout] 34 |             if let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~ ~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.14s
[INFO] running `Command { std: "docker" "inspect" "e09fbde39af0ec0a61b13fad1c49206861c2b5bc85fe8337fcc37706fa7f742e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e09fbde39af0ec0a61b13fad1c49206861c2b5bc85fe8337fcc37706fa7f742e", kill_on_drop: false }`
[INFO] [stdout] e09fbde39af0ec0a61b13fad1c49206861c2b5bc85fe8337fcc37706fa7f742e
[INFO] checking jw3/example-scala-rust against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjw3%2Fexample-scala-rust" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jw3/example-scala-rust on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jw3/example-scala-rust
[INFO] finished tweaking git repo https://github.com/jw3/example-scala-rust
[INFO] tweaked toml for git repo https://github.com/jw3/example-scala-rust written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/jw3/example-scala-rust 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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 14acf43797c13dfab4e763696850e2941578aa97f15640a37275ef8b7fafdcab
[INFO] running `Command { std: "docker" "start" "-a" "14acf43797c13dfab4e763696850e2941578aa97f15640a37275ef8b7fafdcab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "14acf43797c13dfab4e763696850e2941578aa97f15640a37275ef8b7fafdcab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14acf43797c13dfab4e763696850e2941578aa97f15640a37275ef8b7fafdcab", kill_on_drop: false }`
[INFO] [stdout] 14acf43797c13dfab4e763696850e2941578aa97f15640a37275ef8b7fafdcab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 00f3fdc92093fb3d9005c1b92d1a197dcf35646b754d7f530a2314227fc6b00a
[INFO] running `Command { std: "docker" "start" "-a" "00f3fdc92093fb3d9005c1b92d1a197dcf35646b754d7f530a2314227fc6b00a", kill_on_drop: false }`
[INFO] [stderr]     Checking example-scala-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Receiver`, `Sender`
[INFO] [stdout]  --> src/main/rust/lib.rs:4:23
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::sync::mpsc::{Receiver, Sender};
[INFO] [stdout]   |                       ^^^^^^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]  --> src/main/rust/lib.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::sync::{mpsc, Arc, Mutex};
[INFO] [stdout]   |                       ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Receiver`, `Sender`
[INFO] [stdout]  --> src/main/rust/lib.rs:4:23
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::sync::mpsc::{Receiver, Sender};
[INFO] [stdout]   |                       ^^^^^^^^  ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc`, `Mutex`
[INFO] [stdout]  --> src/main/rust/lib.rs:5:23
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::sync::{mpsc, Arc, Mutex};
[INFO] [stdout]   |                       ^^^  ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl B {
[INFO] [stdout]    | ------ associated function in this implementation
[INFO] [stdout] 22 |     fn new(cb: BSink) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `BSink` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:75:6
[INFO] [stdout]    |
[INFO] [stdout] 75 | type BSink = extern "C" fn(i64);
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main/rust/lib.rs:28:17
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 tx.send(i);
[INFO] [stdout]    |                 ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 let _ = tx.send(i);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: for loop over a `Result`. This is more readably written as an `if let` statement
[INFO] [stdout]   --> src/main/rust/lib.rs:34:22
[INFO] [stdout]    |
[INFO] [stdout] 34 |             for i in rx.recv() {
[INFO] [stdout]    |                      ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(for_loops_over_fallibles)]` on by default
[INFO] [stdout] help: to check pattern in a loop use `while let`
[INFO] [stdout]    |
[INFO] [stdout] 34 |             while let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~~~~ ~~~
[INFO] [stdout] help: consider using `if let` to clear intent
[INFO] [stdout]    |
[INFO] [stdout] 34 |             if let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~ ~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:22:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl B {
[INFO] [stdout]    | ------ associated function in this implementation
[INFO] [stdout] 22 |     fn new(cb: BSink) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type alias `BSink` is never used
[INFO] [stdout]   --> src/main/rust/lib.rs:75:6
[INFO] [stdout]    |
[INFO] [stdout] 75 | type BSink = extern "C" fn(i64);
[INFO] [stdout]    |      ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main/rust/lib.rs:28:17
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 tx.send(i);
[INFO] [stdout]    |                 ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 28 |                 let _ = tx.send(i);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: for loop over a `Result`. This is more readably written as an `if let` statement
[INFO] [stdout]   --> src/main/rust/lib.rs:34:22
[INFO] [stdout]    |
[INFO] [stdout] 34 |             for i in rx.recv() {
[INFO] [stdout]    |                      ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(for_loops_over_fallibles)]` on by default
[INFO] [stdout] help: to check pattern in a loop use `while let`
[INFO] [stdout]    |
[INFO] [stdout] 34 |             while let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~~~~ ~~~
[INFO] [stdout] help: consider using `if let` to clear intent
[INFO] [stdout]    |
[INFO] [stdout] 34 |             if let Ok(i) = rx.recv() {
[INFO] [stdout]    |             ~~~~~~~~~~ ~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.16s
[INFO] running `Command { std: "docker" "inspect" "00f3fdc92093fb3d9005c1b92d1a197dcf35646b754d7f530a2314227fc6b00a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "00f3fdc92093fb3d9005c1b92d1a197dcf35646b754d7f530a2314227fc6b00a", kill_on_drop: false }`
[INFO] [stdout] 00f3fdc92093fb3d9005c1b92d1a197dcf35646b754d7f530a2314227fc6b00a