[INFO] fetching crate chapter13_art 0.2.1...
[INFO] checking chapter13_art-0.2.1 against master#cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c for pr-143170
[INFO] extracting crate chapter13_art 0.2.1 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate chapter13_art 0.2.1
[INFO] finished tweaking crates.io crate chapter13_art 0.2.1
[INFO] tweaked toml for crates.io crate chapter13_art 0.2.1 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate chapter13_art 0.2.1 on toolchain cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate chapter13_art 0.2.1 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" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 50f356a0d240f3423bf25637e34bc69c56df3eaa6ed9caee8f934a5b1398521e
[INFO] running `Command { std: "docker" "start" "-a" "50f356a0d240f3423bf25637e34bc69c56df3eaa6ed9caee8f934a5b1398521e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "50f356a0d240f3423bf25637e34bc69c56df3eaa6ed9caee8f934a5b1398521e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "50f356a0d240f3423bf25637e34bc69c56df3eaa6ed9caee8f934a5b1398521e", kill_on_drop: false }`
[INFO] [stdout] 50f356a0d240f3423bf25637e34bc69c56df3eaa6ed9caee8f934a5b1398521e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8160b0c6684d1760e202546511a541acf12984bf2f75b38c0ddc87a5de07e5e1
[INFO] running `Command { std: "docker" "start" "-a" "8160b0c6684d1760e202546511a541acf12984bf2f75b38c0ddc87a5de07e5e1", kill_on_drop: false }`
[INFO] [stderr]     Checking chapter13_art v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]   --> src/lib.rs:32:16
[INFO] [stdout]    |
[INFO] [stdout] 32 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]    |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]   --> src/lib.rs:32:34
[INFO] [stdout]    |
[INFO] [stdout] 32 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]    |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c1`
[INFO] [stdout]   --> src/lib.rs:32:16
[INFO] [stdout]    |
[INFO] [stdout] 32 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]    |                ^^ help: if this is intentional, prefix it with an underscore: `_c1`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c2`
[INFO] [stdout]   --> src/lib.rs:32:34
[INFO] [stdout]    |
[INFO] [stdout] 32 |     pub fn mix(c1: PrimaryColor, c2: PrimaryColor) -> SecondaryColor {
[INFO] [stdout]    |                                  ^^ help: if this is intentional, prefix it with an underscore: `_c2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "8160b0c6684d1760e202546511a541acf12984bf2f75b38c0ddc87a5de07e5e1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8160b0c6684d1760e202546511a541acf12984bf2f75b38c0ddc87a5de07e5e1", kill_on_drop: false }`
[INFO] [stdout] 8160b0c6684d1760e202546511a541acf12984bf2f75b38c0ddc87a5de07e5e1