[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 }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjw3%2Fexample-scala-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c74216224bc4094d05e18b6811c6ebf34e3716ed
[INFO] checking jw3/example-scala-rust against 0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0 for pr-158915-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjw3%2Fexample-scala-rust" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[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-3-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/jw3/example-scala-rust on toolchain 0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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" "+0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:8683fc1fc2eb5c9ac98e0d076ab094b2ffac7f99da555d2b6a2e27f346de2ec7" "sleep" "infinity", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "inspect" "4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92" "/opt/rustwide/cargo-home/bin/cargo" "+0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92" "/opt/rustwide/cargo-home/bin/cargo" "+0335fc7ee9e33d92e03d99f3e2fb0fe6119f3cc0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]     Checking example-scala-rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Receiver` and `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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc` and `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` and `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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Arc` and `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)]` (part of `#[warn(unused)]`) 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: 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)]` (part of `#[warn(unused)]`) 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)]` (part of `#[warn(unused)]`) 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 -             for i in rx.recv() {
[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 -             for i in rx.recv() {
[INFO] [stdout] 34 +             if let Ok(i) = rx.recv() {
[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)]` (part of `#[warn(unused)]`) 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 -             for i in rx.recv() {
[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 -             for i in rx.recv() {
[INFO] [stdout] 34 +             if let Ok(i) = rx.recv() {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.06s
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[INFO] running `Command { std: "docker" "rm" "-f" "4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92", kill_on_drop: false }`
[INFO] [stdout] 4f2c16bc46fca98003cecf4b059a6677141631d47ececa26d8b0d0bc2ae3cb92
