[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 1.95.0 for pr-155915
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhoraoen%2Frust-by-example" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[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-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/horaoen/rust-by-example on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 93762a6de52ec3e050f47b6bf8242634d7e2f9668624b446ff2bd31d511ada93
[INFO] running `Command { std: "docker" "start" "-a" "93762a6de52ec3e050f47b6bf8242634d7e2f9668624b446ff2bd31d511ada93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "93762a6de52ec3e050f47b6bf8242634d7e2f9668624b446ff2bd31d511ada93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "93762a6de52ec3e050f47b6bf8242634d7e2f9668624b446ff2bd31d511ada93", kill_on_drop: false }`
[INFO] [stdout] 93762a6de52ec3e050f47b6bf8242634d7e2f9668624b446ff2bd31d511ada93
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 929f5a67b155d22462120c913a53b08c93ef11964e98b431a1336998d291b7ce
[INFO] running `Command { std: "docker" "start" "-a" "929f5a67b155d22462120c913a53b08c93ef11964e98b431a1336998d291b7ce", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-by-example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> examples/func/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(never_type)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust-by-example` (example "func") due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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)]` (part of `#[warn(unused)]`) 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)]` (part of `#[warn(unused)]`) 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] running `Command { std: "docker" "inspect" "929f5a67b155d22462120c913a53b08c93ef11964e98b431a1336998d291b7ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "929f5a67b155d22462120c913a53b08c93ef11964e98b431a1336998d291b7ce", kill_on_drop: false }`
[INFO] [stdout] 929f5a67b155d22462120c913a53b08c93ef11964e98b431a1336998d291b7ce
