[INFO] cloning repository https://github.com/susan-tu/rust-book-exercises
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/susan-tu/rust-book-exercises" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 519cdd9aec859ec823552009fa8460a3c7610701
[INFO] checking susan-tu/rust-book-exercises against master#fc5af1813307d25a84d633f21e2e53c9376eb547 for pr-144386
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/susan-tu/rust-book-exercises
[INFO] finished tweaking git repo https://github.com/susan-tu/rust-book-exercises
[INFO] tweaked toml for git repo https://github.com/susan-tu/rust-book-exercises written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/susan-tu/rust-book-exercises on toolchain fc5af1813307d25a84d633f21e2e53c9376eb547
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+fc5af1813307d25a84d633f21e2e53c9376eb547" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/susan-tu/rust-book-exercises 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" "+fc5af1813307d25a84d633f21e2e53c9376eb547" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+fc5af1813307d25a84d633f21e2e53c9376eb547" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6cae74579b987c4aaa78e0973c2dd2e1e1251f2da99df48dfc15171f4d498fce
[INFO] running `Command { std: "docker" "start" "-a" "6cae74579b987c4aaa78e0973c2dd2e1e1251f2da99df48dfc15171f4d498fce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6cae74579b987c4aaa78e0973c2dd2e1e1251f2da99df48dfc15171f4d498fce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6cae74579b987c4aaa78e0973c2dd2e1e1251f2da99df48dfc15171f4d498fce", kill_on_drop: false }`
[INFO] [stdout] 6cae74579b987c4aaa78e0973c2dd2e1e1251f2da99df48dfc15171f4d498fce
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+fc5af1813307d25a84d633f21e2e53c9376eb547" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2d2b8a2871aa32324939ec7e916c4545e5adb83a08a261d9408b6d3bdfb83836
[INFO] running `Command { std: "docker" "start" "-a" "2d2b8a2871aa32324939ec7e916c4545e5adb83a08a261d9408b6d3bdfb83836", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]     Checking approx v0.5.0
[INFO] [stderr]     Checking exercises v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]   --> lib.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |         relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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] 99 |         let _ = relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]    --> lib.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |         relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 108 |         let _ = relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: found module declaration for lib.rs
[INFO] [stdout]   --> main.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | mod lib;
[INFO] [stdout]    | ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: lib.rs is the root of this crate's library target
[INFO] [stdout]    = help: to refer to it from other targets, use the library's name as the path
[INFO] [stdout]    = note: `#[warn(special_module_name)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: found module declaration for lib.rs
[INFO] [stdout]   --> main.rs:14:1
[INFO] [stdout]    |
[INFO] [stdout] 14 | mod lib;
[INFO] [stdout]    | ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: lib.rs is the root of this crate's library target
[INFO] [stdout]    = help: to refer to it from other targets, use the library's name as the path
[INFO] [stdout]    = note: `#[warn(special_module_name)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]   --> lib.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |         relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[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] 99 |         let _ = relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]    --> lib.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |         relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 108 |         let _ = relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.15s
[INFO] running `Command { std: "docker" "inspect" "2d2b8a2871aa32324939ec7e916c4545e5adb83a08a261d9408b6d3bdfb83836", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2d2b8a2871aa32324939ec7e916c4545e5adb83a08a261d9408b6d3bdfb83836", kill_on_drop: false }`
[INFO] [stdout] 2d2b8a2871aa32324939ec7e916c4545e5adb83a08a261d9408b6d3bdfb83836