[INFO] cloning repository https://github.com/rust-lang-uz/comprehensive-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rust-lang-uz/comprehensive-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-lang-uz%2Fcomprehensive-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-lang-uz%2Fcomprehensive-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1995260c9b4a48d8d4da77fbc31f23f69a9ace34
[INFO] checking rust-lang-uz/comprehensive-rust against 1.95.0 for pr-155915
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-lang-uz%2Fcomprehensive-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/rust-lang-uz/comprehensive-rust
[INFO] finished tweaking git repo https://github.com/rust-lang-uz/comprehensive-rust
[INFO] tweaked toml for git repo https://github.com/rust-lang-uz/comprehensive-rust written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/rust-lang-uz/comprehensive-rust 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/rust-lang-uz/comprehensive-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" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr]   |
[INFO] [stderr]   = note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr]   = note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr]   = note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
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[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 53c2c398e5d2127ff7ccfddcba6f6dd0e9e70ba84c87c2f9d739777ea0046a05
[INFO] running `Command { std: "docker" "start" "-a" "53c2c398e5d2127ff7ccfddcba6f6dd0e9e70ba84c87c2f9d739777ea0046a05", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "53c2c398e5d2127ff7ccfddcba6f6dd0e9e70ba84c87c2f9d739777ea0046a05", kill_on_drop: false }`
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[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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "start" "-a" "af18bf8d970f734f51b2054090fa0b10cf5b91c54a609250795c552ad6427677", kill_on_drop: false }`
[INFO] [stderr] warning: virtual workspace defaulting to `resolver = "1"` despite one or more workspace members being on edition 2021 which implies `resolver = "2"`
[INFO] [stderr]   |
[INFO] [stderr]   = note: to keep the current resolver, specify `workspace.resolver = "1"` in the workspace root's manifest
[INFO] [stderr]   = note: to use the edition 2021 resolver, specify `workspace.resolver = "2"` in the workspace root's manifest
[INFO] [stderr]   = note: for more details see https://doc.rust-lang.org/cargo/reference/resolver.html#resolver-versions
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[INFO] [stderr]    Compiling derive_more v0.99.17
[INFO] [stderr]    Compiling pin-project-internal v1.0.12
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[INFO] [stderr]     Checking zerocopy-example v0.1.0 (/opt/rustwide/workdir/src/bare-metal/useful-crates/zerocopy-example)
[INFO] [stdout] warning: variant `Out` is never constructed
[INFO] [stdout]   --> src/bare-metal/useful-crates/zerocopy-example/src/main.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | enum RequestType {
[INFO] [stdout]    |      ----------- variant in this enum
[INFO] [stdout] ...
[INFO] [stdout] 23 |     Out = 1,
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `RequestType` 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: variant `Out` is never constructed
[INFO] [stdout]   --> src/bare-metal/useful-crates/zerocopy-example/src/main.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | enum RequestType {
[INFO] [stdout]    |      ----------- variant in this enum
[INFO] [stdout] ...
[INFO] [stdout] 23 |     Out = 1,
[INFO] [stdout]    |     ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `RequestType` 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] 
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[INFO] [stderr]     Checking tokio-native-tls v0.3.1
[INFO] [stderr]     Checking tokio-tungstenite v0.18.0
[INFO] [stderr]     Checking tokio-stream v0.1.12
[INFO] [stderr]     Checking h2 v0.3.17
[INFO] [stderr]     Checking tokio-websockets v0.3.2
[INFO] [stderr]     Checking chat-async v0.1.0 (/opt/rustwide/workdir/src/exercises/concurrency/chat-async)
[INFO] [stderr]     Checking string_cache v0.8.7
[INFO] [stderr]     Checking serde_urlencoded v0.7.1
[INFO] [stderr]     Checking serde_json v1.0.95
[INFO] [stderr]     Checking toml v0.5.11
[INFO] [stderr]     Checking elasticlunr-rs v3.0.2
[INFO] [stderr]     Checking handlebars v4.3.6
[INFO] [stderr]     Checking scraper v0.15.0
[INFO] [stderr]     Checking ammonia v3.3.0
[INFO] [stderr]     Checking hyper v0.14.25
[INFO] [stderr]     Checking hyper-tls v0.5.0
[INFO] [stderr]     Checking warp v0.3.4
[INFO] [stderr]     Checking reqwest v0.11.16
[INFO] [stderr]     Checking comprehensive-rust v0.1.0 (/opt/rustwide/workdir/src/exercises)
[INFO] [stdout] warning: field `callback` is never read
[INFO] [stdout]   --> src/exercises/day-3/simple-gui.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 43 | pub struct Button {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 44 |     label: Label,
[INFO] [stdout] 45 |     callback: Box<dyn FnMut()>,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `left`
[INFO] [stdout]   --> src/exercises/concurrency/dining-philosophers.rs:43:13
[INFO] [stdout]    |
[INFO] [stdout] 43 |         let left = self.left_fork.lock().unwrap();
[INFO] [stdout]    |             ^^^^ help: if this is intentional, prefix it with an underscore: `_left`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `right`
[INFO] [stdout]   --> src/exercises/concurrency/dining-philosophers.rs:44:13
[INFO] [stdout]    |
[INFO] [stdout] 44 |         let right = self.right_fork.lock().unwrap();
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_right`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `callback` is never read
[INFO] [stdout]   --> src/exercises/day-3/simple-gui.rs:45:5
[INFO] [stdout]    |
[INFO] [stdout] 43 | pub struct Button {
[INFO] [stdout]    |            ------ field in this struct
[INFO] [stdout] 44 |     label: Label,
[INFO] [stdout] 45 |     callback: Box<dyn FnMut()>,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `library`
[INFO] [stdout]    --> src/exercises/day-1/book-library.rs:115:9
[INFO] [stdout]     |
[INFO] [stdout] 115 |     let library = Library::new();
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_library`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `left`
[INFO] [stdout]   --> src/exercises/concurrency/dining-philosophers.rs:43:13
[INFO] [stdout]    |
[INFO] [stdout] 43 |         let left = self.left_fork.lock().unwrap();
[INFO] [stdout]    |             ^^^^ help: if this is intentional, prefix it with an underscore: `_left`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `right`
[INFO] [stdout]   --> src/exercises/concurrency/dining-philosophers.rs:44:13
[INFO] [stdout]    |
[INFO] [stdout] 44 |         let right = self.right_fork.lock().unwrap();
[INFO] [stdout]    |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_right`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `library`
[INFO] [stdout]    --> src/exercises/day-1/book-library.rs:115:9
[INFO] [stdout]     |
[INFO] [stdout] 115 |     let library = Library::new();
[INFO] [stdout]     |         ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_library`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `books` is never read
[INFO] [stdout]   --> src/exercises/day-1/book-library.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 16 | struct Library {
[INFO] [stdout]    |        ------- field in this struct
[INFO] [stdout] 17 |     books: Vec<Book>,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `title` and `year` are never read
[INFO] [stdout]   --> src/exercises/day-1/book-library.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 20 | struct Book {
[INFO] [stdout]    |        ---- fields in this struct
[INFO] [stdout] 21 |     title: String,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout] 22 |     year: u16,
[INFO] [stdout]    |     ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/exercises/day-1/book-library.rs:27:8
[INFO] [stdout]    |
[INFO] [stdout] 25 | impl Book {
[INFO] [stdout]    | --------- associated function in this implementation
[INFO] [stdout] 26 |     // This is a constructor, used below.
[INFO] [stdout] 27 |     fn new(title: &str, year: u16) -> Book {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: methods `len`, `is_empty`, `add_book`, `print_books`, and `oldest_book` are never used
[INFO] [stdout]   --> src/exercises/day-1/book-library.rs:55:8
[INFO] [stdout]    |
[INFO] [stdout] 41 | impl Library {
[INFO] [stdout]    | ------------ methods in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 55 |     fn len(&self) -> usize {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 64 |     fn is_empty(&self) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 73 |     fn add_book(&mut self, book: Book) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 82 |     fn print_books(&self) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 93 |     fn oldest_book(&self) -> Option<&Book> {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking mdbook v0.4.28
[INFO] [stderr]     Checking mdbook-exerciser v0.1.0 (/opt/rustwide/workdir/mdbook-exerciser)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 51.17s
[INFO] [stderr] warning: the following packages contain code that will be rejected by a future version of Rust: openssl v0.10.49
[INFO] [stderr] note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 2`
[INFO] running `Command { std: "docker" "inspect" "af18bf8d970f734f51b2054090fa0b10cf5b91c54a609250795c552ad6427677", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af18bf8d970f734f51b2054090fa0b10cf5b91c54a609250795c552ad6427677", kill_on_drop: false }`
[INFO] [stdout] af18bf8d970f734f51b2054090fa0b10cf5b91c54a609250795c552ad6427677
