[INFO] cloning repository https://github.com/spartanhooah/rust_book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/spartanhooah/rust_book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspartanhooah%2Frust_book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspartanhooah%2Frust_book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 129164788eb706ec869a92400d3b216dba4cdcd1
[INFO] building spartanhooah/rust_book against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fspartanhooah%2Frust_book" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/spartanhooah/rust_book on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/spartanhooah/rust_book
[INFO] finished tweaking git repo https://github.com/spartanhooah/rust_book
[INFO] tweaked toml for git repo https://github.com/spartanhooah/rust_book written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/spartanhooah/rust_book 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1309525c528cbd03ae0865bd18aa238c2843f70cf33f1f31d79b79c17a3e44e0
[INFO] running `Command { std: "docker" "start" "-a" "1309525c528cbd03ae0865bd18aa238c2843f70cf33f1f31d79b79c17a3e44e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1309525c528cbd03ae0865bd18aa238c2843f70cf33f1f31d79b79c17a3e44e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1309525c528cbd03ae0865bd18aa238c2843f70cf33f1f31d79b79c17a3e44e0", kill_on_drop: false }`
[INFO] [stdout] 1309525c528cbd03ae0865bd18aa238c2843f70cf33f1f31d79b79c17a3e44e0
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 276385f4277431d917d23dfd0c548d39c2c725fcbe50cb771a3b611cd98d0e12
[INFO] running `Command { std: "docker" "start" "-a" "276385f4277431d917d23dfd0c548d39c2c725fcbe50cb771a3b611cd98d0e12", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.147
[INFO] [stderr]    Compiling getrandom v0.2.10
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling rust_book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]  --> src/bin/enums/main.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let home = IpAddr::V4(127, 0, 0, 1);
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loopback`
[INFO] [stdout]  --> src/bin/enums/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let loopback = IpAddr::V6(String::from("::1"));
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loopback`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six`
[INFO] [stdout]   --> src/bin/matches/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let six = plus_one(five);
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_six`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `none`
[INFO] [stdout]   --> src/bin/matches/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let none = plus_one(None);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_none`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0`, `1`, `2`, and `3` are never read
[INFO] [stdout]  --> src/bin/enums/main.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 |         V4(u8, u8, u8, u8),
[INFO] [stdout]   |         -- ^^  ^^  ^^  ^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         fields in this variant
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]   |
[INFO] [stdout] 3 |         V4((), (), (), ()),
[INFO] [stdout]   |            ~~  ~~  ~~  ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]  --> src/bin/enums/main.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 |         V6(String)
[INFO] [stdout]   |         -- ^^^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         field in this variant
[INFO] [stdout]   |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]   |
[INFO] [stdout] 4 |         V6(())
[INFO] [stdout]   |            ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/bin/enums/main.rs:13:15
[INFO] [stdout]    |
[INFO] [stdout] 13 |         Write(String),
[INFO] [stdout]    |         ----- ^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         field in this variant
[INFO] [stdout]    |
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 13 |         Write(()),
[INFO] [stdout]    |               ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num_spaces`
[INFO] [stdout]   --> src/bin/matches/main.rs:52:20
[INFO] [stdout]    |
[INFO] [stdout] 52 |     fn move_player(num_spaces: u8) {}
[INFO] [stdout]    |                    ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_num_spaces`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variants `Quit`, `Move`, and `ChangeColor` are never constructed
[INFO] [stdout]   --> src/bin/enums/main.rs:11:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     enum Message {
[INFO] [stdout]    |          ------- variants in this enum
[INFO] [stdout] 11 |         Quit,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 12 |         Move { x: i32, y: i32 },
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 13 |         Write(String),
[INFO] [stdout] 14 |         ChangeColor(i32, i32, i32),
[INFO] [stdout]    |         ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `UsState` is never used
[INFO] [stdout]  --> src/bin/matches/main.rs:3:10
[INFO] [stdout]   |
[INFO] [stdout] 3 |     enum UsState {
[INFO] [stdout]   |          ^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Coin` is never used
[INFO] [stdout]  --> src/bin/matches/main.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 9 |     enum Coin {
[INFO] [stdout]   |          ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `value_in_cents` is never used
[INFO] [stdout]   --> src/bin/matches/main.rs:16:8
[INFO] [stdout]    |
[INFO] [stdout] 16 |     fn value_in_cents(coin: &Coin) -> u8 {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `area` and `square` are never used
[INFO] [stdout]   --> src/bin/rectangles/main.rs:8:8
[INFO] [stdout]    |
[INFO] [stdout] 7  | impl Rectangle {
[INFO] [stdout]    | -------------- associated items in this implementation
[INFO] [stdout] 8  |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 17 |     fn square(size: u32) -> Self {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.92s
[INFO] running `Command { std: "docker" "inspect" "276385f4277431d917d23dfd0c548d39c2c725fcbe50cb771a3b611cd98d0e12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "276385f4277431d917d23dfd0c548d39c2c725fcbe50cb771a3b611cd98d0e12", kill_on_drop: false }`
[INFO] [stdout] 276385f4277431d917d23dfd0c548d39c2c725fcbe50cb771a3b611cd98d0e12
[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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2ed14c7ee5cfd52091bf78044b27efbb4ea85d1e90b1f9fca8740b0cb61a9bc0
[INFO] running `Command { std: "docker" "start" "-a" "2ed14c7ee5cfd52091bf78044b27efbb4ea85d1e90b1f9fca8740b0cb61a9bc0", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `home`
[INFO] [stdout]  --> src/bin/enums/main.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let home = IpAddr::V4(127, 0, 0, 1);
[INFO] [stdout]   |         ^^^^ help: if this is intentional, prefix it with an underscore: `_home`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `loopback`
[INFO] [stdout]  --> src/bin/enums/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let loopback = IpAddr::V6(String::from("::1"));
[INFO] [stdout]   |         ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_loopback`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `six`
[INFO] [stdout]   --> src/bin/matches/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let six = plus_one(five);
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_six`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `none`
[INFO] [stdout]   --> src/bin/matches/main.rs:39:9
[INFO] [stdout]    |
[INFO] [stdout] 39 |     let none = plus_one(None);
[INFO] [stdout]    |         ^^^^ help: if this is intentional, prefix it with an underscore: `_none`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num_spaces`
[INFO] [stdout]   --> src/bin/matches/main.rs:52:20
[INFO] [stdout]    |
[INFO] [stdout] 52 |     fn move_player(num_spaces: u8) {}
[INFO] [stdout]    |                    ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_num_spaces`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `area` and `square` are never used
[INFO] [stdout]   --> src/bin/rectangles/main.rs:8:8
[INFO] [stdout]    |
[INFO] [stdout] 7  | impl Rectangle {
[INFO] [stdout]    | -------------- associated items in this implementation
[INFO] [stdout] 8  |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 17 |     fn square(size: u32) -> Self {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.17s
[INFO] running `Command { std: "docker" "inspect" "2ed14c7ee5cfd52091bf78044b27efbb4ea85d1e90b1f9fca8740b0cb61a9bc0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ed14c7ee5cfd52091bf78044b27efbb4ea85d1e90b1f9fca8740b0cb61a9bc0", kill_on_drop: false }`
[INFO] [stdout] 2ed14c7ee5cfd52091bf78044b27efbb4ea85d1e90b1f9fca8740b0cb61a9bc0