[INFO] cloning repository https://github.com/theeighthofseptember/learn_structs_RUST
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/theeighthofseptember/learn_structs_RUST" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftheeighthofseptember%2Flearn_structs_RUST", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftheeighthofseptember%2Flearn_structs_RUST'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3e0eb58daa1cf72b0291cc1ca3d2186edb251c6f
[INFO] checking theeighthofseptember/learn_structs_RUST against master#f8f6997469237299c1d60814c7b9828602a1f8e4 for pr-143808
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftheeighthofseptember%2Flearn_structs_RUST" "/workspace/builds/worker-3-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/theeighthofseptember/learn_structs_RUST
[INFO] finished tweaking git repo https://github.com/theeighthofseptember/learn_structs_RUST
[INFO] tweaked toml for git repo https://github.com/theeighthofseptember/learn_structs_RUST written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/theeighthofseptember/learn_structs_RUST on toolchain f8f6997469237299c1d60814c7b9828602a1f8e4
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+f8f6997469237299c1d60814c7b9828602a1f8e4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/theeighthofseptember/learn_structs_RUST 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" "+f8f6997469237299c1d60814c7b9828602a1f8e4" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+f8f6997469237299c1d60814c7b9828602a1f8e4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3bf6039bb4c2433b1e680f2d48430b0b8f44799a6c6dcc052cf8caef60159cf0
[INFO] running `Command { std: "docker" "start" "-a" "3bf6039bb4c2433b1e680f2d48430b0b8f44799a6c6dcc052cf8caef60159cf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3bf6039bb4c2433b1e680f2d48430b0b8f44799a6c6dcc052cf8caef60159cf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3bf6039bb4c2433b1e680f2d48430b0b8f44799a6c6dcc052cf8caef60159cf0", kill_on_drop: false }`
[INFO] [stdout] 3bf6039bb4c2433b1e680f2d48430b0b8f44799a6c6dcc052cf8caef60159cf0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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" "+f8f6997469237299c1d60814c7b9828602a1f8e4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7e689679cccae61b89af5f0b10a8834d4fb4afdf244796b7723938367fbfcae6
[INFO] running `Command { std: "docker" "start" "-a" "7e689679cccae61b89af5f0b10a8834d4fb4afdf244796b7723938367fbfcae6", kill_on_drop: false }`
[INFO] [stderr]     Checking learn_struct v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `book2`
[INFO] [stdout]   --> src/main.rs:86:13
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let mut book2 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3`
[INFO] [stdout]   --> src/main.rs:92:13
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut book3 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book4`
[INFO] [stdout]   --> src/main.rs:98:13
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let mut book4 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book4`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book5`
[INFO] [stdout]    --> src/main.rs:104:13
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut book5 = Book {
[INFO] [stdout]     |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book5`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let mut book2 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut book3 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:98:9
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let mut book4 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:104:9
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut book5 = Book {
[INFO] [stdout]     |         ----^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book2`
[INFO] [stdout]   --> src/main.rs:86:13
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let mut book2 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book2`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3`
[INFO] [stdout]   --> src/main.rs:92:13
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut book3 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book4`
[INFO] [stdout]   --> src/main.rs:98:13
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let mut book4 = Book {
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book4`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book5`
[INFO] [stdout]    --> src/main.rs:104:13
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut book5 = Book {
[INFO] [stdout]     |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_book5`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:86:9
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let mut book2 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:92:9
[INFO] [stdout]    |
[INFO] [stdout] 92 |     let mut book3 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:98:9
[INFO] [stdout]    |
[INFO] [stdout] 98 |     let mut book4 = Book {
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/main.rs:104:9
[INFO] [stdout]     |
[INFO] [stdout] 104 |     let mut book5 = Book {
[INFO] [stdout]     |         ----^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "7e689679cccae61b89af5f0b10a8834d4fb4afdf244796b7723938367fbfcae6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e689679cccae61b89af5f0b10a8834d4fb4afdf244796b7723938367fbfcae6", kill_on_drop: false }`
[INFO] [stdout] 7e689679cccae61b89af5f0b10a8834d4fb4afdf244796b7723938367fbfcae6