[INFO] crate munkres 0.4.0 is already in cache
[INFO] extracting crate munkres 0.4.0 into work/ex/clippy-test-run/sources/stable/reg/munkres/0.4.0
[INFO] extracting crate munkres 0.4.0 into work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/munkres/0.4.0
[INFO] validating manifest of munkres-0.4.0 on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of munkres-0.4.0 on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing munkres-0.4.0
[INFO] finished frobbing munkres-0.4.0
[INFO] frobbed toml for munkres-0.4.0 written to work/ex/clippy-test-run/sources/stable/reg/munkres/0.4.0/Cargo.toml
[INFO] started frobbing munkres-0.4.0
[INFO] finished frobbing munkres-0.4.0
[INFO] frobbed toml for munkres-0.4.0 written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/munkres/0.4.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting munkres-0.4.0 against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-6/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/reg/munkres/0.4.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] db5d493248f7c7d3be88640cf010329d8ac98bcd4dc4a01a9a4a9260bee3e7a7
[INFO] running `"docker" "start" "-a" "db5d493248f7c7d3be88640cf010329d8ac98bcd4dc4a01a9a4a9260bee3e7a7"`
[INFO] [stderr]     Checking munkres v0.4.0 (/opt/crater/workdir)
[INFO] [stderr] warning: redundant field names in struct initialization
[INFO] [stderr]   --> src/coverage.rs:28:13
[INFO] [stderr]    |
[INFO] [stderr] 28 |             n: n,
[INFO] [stderr]    |             ^^^^ help: replace it with: `n`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::redundant_field_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_field_names
[INFO] [stderr] 
[INFO] [stderr] warning: redundant field names in struct initialization
[INFO] [stderr]   --> src/coverage.rs:28:13
[INFO] [stderr]    |
[INFO] [stderr] 28 |             n: n,
[INFO] [stderr]    |             ^^^^ help: replace it with: `n`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::redundant_field_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_field_names
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/coverage.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     return true;
[INFO] [stderr]    |     ^^^^^^^^^^^^ help: remove `return` as shown: `true`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/coverage.rs:58:9
[INFO] [stderr]    |
[INFO] [stderr] 58 |         return None;
[INFO] [stderr]    |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/mark_matrix.rs:93:9
[INFO] [stderr]    |
[INFO] [stderr] 93 |         return None;
[INFO] [stderr]    |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/mark_matrix.rs:102:9
[INFO] [stderr]     |
[INFO] [stderr] 102 |         return None;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/mark_matrix.rs:111:9
[INFO] [stderr]     |
[INFO] [stderr] 111 |         return None;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:151:5
[INFO] [stderr]     |
[INFO] [stderr] 151 |     Step1,
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::enum_variant_names)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:152:5
[INFO] [stderr]     |
[INFO] [stderr] 152 |     Step2,
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:153:5
[INFO] [stderr]     |
[INFO] [stderr] 153 |     Step3,
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:154:5
[INFO] [stderr]     |
[INFO] [stderr] 154 |     Step4(Option<usize>),
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:155:5
[INFO] [stderr]     |
[INFO] [stderr] 155 |     Step5(usize, usize),
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: Variant name starts with the enum's name
[INFO] [stderr]    --> src/lib.rs:156:5
[INFO] [stderr]     |
[INFO] [stderr] 156 |     Step6,
[INFO] [stderr]     |     ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#enum_variant_names
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:168:5
[INFO] [stderr]     |
[INFO] [stderr] 168 |     return Step::Step2;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Step::Step2`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:196:5
[INFO] [stderr]     |
[INFO] [stderr] 196 |     return Step::Step3;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Step::Step3`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:312:5
[INFO] [stderr]     |
[INFO] [stderr] 312 |     return Step::Step3;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Step::Step3`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:354:5
[INFO] [stderr]     |
[INFO] [stderr] 354 |     return Step::Step4(None);
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Step::Step4(None)`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:410:5
[INFO] [stderr]     |
[INFO] [stderr] 410 |     return Ok(matching);
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Ok(matching)`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: #![feature] may not be used on the stable release channel
[INFO] [stderr]  --> src/lib.rs:1:19
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![cfg_attr(test, feature(test))]
[INFO] [stderr]   |                   ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `munkres`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] warning: this loop could be written as a `while let` loop
[INFO] [stderr]    --> src/lib.rs:286:5
[INFO] [stderr]     |
[INFO] [stderr] 286 | /     loop {
[INFO] [stderr] 287 | |         match marks.find_first_star_in_col(prev_col) {
[INFO] [stderr] 288 | |             Some(row) => {
[INFO] [stderr] 289 | |                 path.push((row, prev_col));
[INFO] [stderr] ...   |
[INFO] [stderr] 302 | |         }
[INFO] [stderr] 303 | |     }
[INFO] [stderr]     | |_____^ help: try: `while let Some(row) = marks.find_first_star_in_col(prev_col) { .. }`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::while_let_loop)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#while_let_loop
[INFO] [stderr] 
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "db5d493248f7c7d3be88640cf010329d8ac98bcd4dc4a01a9a4a9260bee3e7a7"`
[INFO] running `"docker" "rm" "-f" "db5d493248f7c7d3be88640cf010329d8ac98bcd4dc4a01a9a4a9260bee3e7a7"`
[INFO] [stdout] db5d493248f7c7d3be88640cf010329d8ac98bcd4dc4a01a9a4a9260bee3e7a7