[INFO] cloning repository https://github.com/horaoen/rust-by-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/horaoen/rust-by-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhoraoen%2Frust-by-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhoraoen%2Frust-by-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 61a8c277d6960953e7c433423575c1e45a6659c2
[INFO] checking horaoen/rust-by-example against try#44e31dee3cf6f37b4f652572897bb0eb25c477ee for pr-139763
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhoraoen%2Frust-by-example" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/horaoen/rust-by-example on toolchain 44e31dee3cf6f37b4f652572897bb0eb25c477ee
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/horaoen/rust-by-example
[INFO] finished tweaking git repo https://github.com/horaoen/rust-by-example
[INFO] tweaked toml for git repo https://github.com/horaoen/rust-by-example written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/horaoen/rust-by-example 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" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 14aaecbd9cf8440001c3dea7bfa508bbf76a411e32b67694031118182c8487d4
[INFO] running `Command { std: "docker" "start" "-a" "14aaecbd9cf8440001c3dea7bfa508bbf76a411e32b67694031118182c8487d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "14aaecbd9cf8440001c3dea7bfa508bbf76a411e32b67694031118182c8487d4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14aaecbd9cf8440001c3dea7bfa508bbf76a411e32b67694031118182c8487d4", kill_on_drop: false }`
[INFO] [stdout] 14aaecbd9cf8440001c3dea7bfa508bbf76a411e32b67694031118182c8487d4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+44e31dee3cf6f37b4f652572897bb0eb25c477ee" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 037f0739bfe55714fcae6cb9e40481f2f5bd5b12063e7105bb22bd7f376d4d3e
[INFO] running `Command { std: "docker" "start" "-a" "037f0739bfe55714fcae6cb9e40481f2f5bd5b12063e7105bb22bd7f376d4d3e", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-by-example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> examples/expressions/main.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         x * 2;
[INFO] [stdout]    |         ^^^^^ the arithmetic operation produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let _ = x * 2;
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `value` is never read
[INFO] [stdout]   --> examples/conversion/main.rs:10:5
[INFO] [stdout]    |
[INFO] [stdout] 9  | struct Number {
[INFO] [stdout]    |        ------ field in this struct
[INFO] [stdout] 10 |     value: i32,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Number` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> examples/conversion/tostring.rs:11:12
[INFO] [stdout]    |
[INFO] [stdout] 10 | impl Circle {
[INFO] [stdout]    | ----------- associated function in this implementation
[INFO] [stdout] 11 |     pub fn new(radius: i32) -> Self {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.11s
[INFO] running `Command { std: "docker" "inspect" "037f0739bfe55714fcae6cb9e40481f2f5bd5b12063e7105bb22bd7f376d4d3e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "037f0739bfe55714fcae6cb9e40481f2f5bd5b12063e7105bb22bd7f376d4d3e", kill_on_drop: false }`
[INFO] [stdout] 037f0739bfe55714fcae6cb9e40481f2f5bd5b12063e7105bb22bd7f376d4d3e