[INFO] fetching crate ku 0.1.0...
[INFO] building ku-0.1.0 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate ku 0.1.0 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate ku 0.1.0 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 crates.io crate ku 0.1.0
[INFO] finished tweaking crates.io crate ku 0.1.0
[INFO] tweaked toml for crates.io crate ku 0.1.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 18 packages to latest compatible versions
[INFO] [stderr]       Adding clap v2.34.0 (available: v4.5.23)
[INFO] [stderr]       Adding rand v0.4.6 (available: v0.8.5)
[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] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[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] 573cb6e2238d228faa75ece160c25f1ade4158bf36d47d126d5dd37dea041d43
[INFO] running `Command { std: "docker" "start" "-a" "573cb6e2238d228faa75ece160c25f1ade4158bf36d47d126d5dd37dea041d43", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "573cb6e2238d228faa75ece160c25f1ade4158bf36d47d126d5dd37dea041d43", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "573cb6e2238d228faa75ece160c25f1ade4158bf36d47d126d5dd37dea041d43", kill_on_drop: false }`
[INFO] [stdout] 573cb6e2238d228faa75ece160c25f1ade4158bf36d47d126d5dd37dea041d43
[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] c5045999544212fd816f4c13098a1cca9460d41fafc7a3ae4ba0da0ea35ec6ec
[INFO] running `Command { std: "docker" "start" "-a" "c5045999544212fd816f4c13098a1cca9460d41fafc7a3ae4ba0da0ea35ec6ec", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]    Compiling ansi_term v0.12.1
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling clap v2.34.0
[INFO] [stderr]    Compiling ku v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:53:14
[INFO] [stdout]    |
[INFO] [stdout] 53 |             0...49 => Unplayable,
[INFO] [stdout]    |              ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:54:15
[INFO] [stdout]    |
[INFO] [stdout] 54 |             50...150 => Beginner,
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:55:16
[INFO] [stdout]    |
[INFO] [stdout] 55 |             151...250 => Easy,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:56:16
[INFO] [stdout]    |
[INFO] [stdout] 56 |             251...400 => Intermediate,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:57:16
[INFO] [stdout]    |
[INFO] [stdout] 57 |             401...550 => Difficult,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:37:25
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<dyn Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:13:16
[INFO] [stdout]    |
[INFO] [stdout] 13 |     SolveError(SolveError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[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 |     SolveError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:14:16
[INFO] [stdout]    |
[INFO] [stdout] 14 |     ParseError(ParseError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 14 |     ParseError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:15:13
[INFO] [stdout]    |
[INFO] [stdout] 15 |     IoError(IoError),
[INFO] [stdout]    |     ------- ^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 15 |     IoError(()),
[INFO] [stdout]    |             ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.50s
[INFO] running `Command { std: "docker" "inspect" "c5045999544212fd816f4c13098a1cca9460d41fafc7a3ae4ba0da0ea35ec6ec", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c5045999544212fd816f4c13098a1cca9460d41fafc7a3ae4ba0da0ea35ec6ec", kill_on_drop: false }`
[INFO] [stdout] c5045999544212fd816f4c13098a1cca9460d41fafc7a3ae4ba0da0ea35ec6ec
[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] ebf780dfbc0eb5791782b4ca6ffb0109dbfe29e0fbfc79691dc538b5ec43884a
[INFO] running `Command { std: "docker" "start" "-a" "ebf780dfbc0eb5791782b4ca6ffb0109dbfe29e0fbfc79691dc538b5ec43884a", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:53:14
[INFO] [stdout]    |
[INFO] [stdout] 53 |             0...49 => Unplayable,
[INFO] [stdout]    |              ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:54:15
[INFO] [stdout]    |
[INFO] [stdout] 54 |             50...150 => Beginner,
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling ku v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:55:16
[INFO] [stdout]    |
[INFO] [stdout] 55 |             151...250 => Easy,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:56:16
[INFO] [stdout]    |
[INFO] [stdout] 56 |             251...400 => Intermediate,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:57:16
[INFO] [stdout]    |
[INFO] [stdout] 57 |             401...550 => Difficult,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:37:25
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<dyn Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:13:16
[INFO] [stdout]    |
[INFO] [stdout] 13 |     SolveError(SolveError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[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 |     SolveError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:14:16
[INFO] [stdout]    |
[INFO] [stdout] 14 |     ParseError(ParseError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 14 |     ParseError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:15:13
[INFO] [stdout]    |
[INFO] [stdout] 15 |     IoError(IoError),
[INFO] [stdout]    |     ------- ^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 15 |     IoError(()),
[INFO] [stdout]    |             ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:37:25
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut reader: Box<dyn Read> = if matches.is_present("INPUT") {
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:53:14
[INFO] [stdout]    |
[INFO] [stdout] 53 |             0...49 => Unplayable,
[INFO] [stdout]    |              ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:54:15
[INFO] [stdout]    |
[INFO] [stdout] 54 |             50...150 => Beginner,
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:55:16
[INFO] [stdout]    |
[INFO] [stdout] 55 |             151...250 => Easy,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:56:16
[INFO] [stdout]    |
[INFO] [stdout] 56 |             251...400 => Intermediate,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/sol.rs:57:16
[INFO] [stdout]    |
[INFO] [stdout] 57 |             401...550 => Difficult,
[INFO] [stdout]    |                ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:593:22
[INFO] [stdout]     |
[INFO] [stdout] 593 |                     0...2 => 0,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:594:22
[INFO] [stdout]     |
[INFO] [stdout] 594 |                     3...5 => 3,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:595:22
[INFO] [stdout]     |
[INFO] [stdout] 595 |                     6...8 => 6,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:599:22
[INFO] [stdout]     |
[INFO] [stdout] 599 |                     0...2 => 0,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:600:22
[INFO] [stdout]     |
[INFO] [stdout] 600 |                     3...5 => 3,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:601:22
[INFO] [stdout]     |
[INFO] [stdout] 601 |                     6...8 => 6,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:611:22
[INFO] [stdout]     |
[INFO] [stdout] 611 |                     0...3 => 0,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:612:22
[INFO] [stdout]     |
[INFO] [stdout] 612 |                     4...7 => 4,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:613:22
[INFO] [stdout]     |
[INFO] [stdout] 613 |                     8...11 => 8,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:614:23
[INFO] [stdout]     |
[INFO] [stdout] 614 |                     12...15 => 12,
[INFO] [stdout]     |                       ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:618:22
[INFO] [stdout]     |
[INFO] [stdout] 618 |                     0...3 => 0,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:619:22
[INFO] [stdout]     |
[INFO] [stdout] 619 |                     4...7 => 4,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:620:22
[INFO] [stdout]     |
[INFO] [stdout] 620 |                     8...11 => 8,
[INFO] [stdout]     |                      ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]    --> src/sudoku.rs:621:23
[INFO] [stdout]     |
[INFO] [stdout] 621 |                     12...15 => 12,
[INFO] [stdout]     |                       ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:13:16
[INFO] [stdout]    |
[INFO] [stdout] 13 |     SolveError(SolveError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[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 |     SolveError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:14:16
[INFO] [stdout]    |
[INFO] [stdout] 14 |     ParseError(ParseError),
[INFO] [stdout]    |     ---------- ^^^^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 14 |     ParseError(()),
[INFO] [stdout]    |                ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:15:13
[INFO] [stdout]    |
[INFO] [stdout] 15 |     IoError(IoError),
[INFO] [stdout]    |     ------- ^^^^^^^
[INFO] [stdout]    |     |
[INFO] [stdout]    |     field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Error` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[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] 15 |     IoError(()),
[INFO] [stdout]    |             ~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to `<[T; N] as IntoIterator>::into_iter` in Rust 2021
[INFO] [stdout]    --> src/sudoku.rs:521:71
[INFO] [stdout]     |
[INFO] [stdout] 521 |         for vec in [vec![], vec![Some(Element(1)), Some(Element(2))]].into_iter() {
[INFO] [stdout]     |                                                                       ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 521 |         for vec in [vec![], vec![Some(Element(1)), Some(Element(2))]].iter() {
[INFO] [stdout]     |                                                                       ~~~~
[INFO] [stdout] help: or remove `.into_iter()` to iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 521 -         for vec in [vec![], vec![Some(Element(1)), Some(Element(2))]].into_iter() {
[INFO] [stdout] 521 +         for vec in [vec![], vec![Some(Element(1)), Some(Element(2))]] {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to `<[T; N] as IntoIterator>::into_iter` in Rust 2021
[INFO] [stdout]    --> src/sudoku.rs:531:77
[INFO] [stdout]     |
[INFO] [stdout] 531 |         for vec in [vec![], vec![Some(Element(2)), Some(Element(6)), None]].into_iter() {
[INFO] [stdout]     |                                                                             ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/IntoIterator-for-arrays.html>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 531 |         for vec in [vec![], vec![Some(Element(2)), Some(Element(6)), None]].iter() {
[INFO] [stdout]     |                                                                             ~~~~
[INFO] [stdout] help: or remove `.into_iter()` to iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 531 -         for vec in [vec![], vec![Some(Element(2)), Some(Element(6)), None]].into_iter() {
[INFO] [stdout] 531 +         for vec in [vec![], vec![Some(Element(2)), Some(Element(6)), None]] {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.59s
[INFO] running `Command { std: "docker" "inspect" "ebf780dfbc0eb5791782b4ca6ffb0109dbfe29e0fbfc79691dc538b5ec43884a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ebf780dfbc0eb5791782b4ca6ffb0109dbfe29e0fbfc79691dc538b5ec43884a", kill_on_drop: false }`
[INFO] [stdout] ebf780dfbc0eb5791782b4ca6ffb0109dbfe29e0fbfc79691dc538b5ec43884a