[INFO] cloning repository https://github.com/nosewings/aoc2021
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nosewings/aoc2021" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnosewings%2Faoc2021", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnosewings%2Faoc2021'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 63c6c8458e56d0acb16252c9c0aa48ad56ea0b62
[INFO] documenting nosewings/aoc2021 against beta-2023-04-20 for beta-1.70-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnosewings%2Faoc2021" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nosewings/aoc2021 on toolchain beta-2023-04-20
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2023-04-20" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nosewings/aoc2021
[INFO] finished tweaking git repo https://github.com/nosewings/aoc2021
[INFO] tweaked toml for git repo https://github.com/nosewings/aoc2021 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/nosewings/aoc2021 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" "+beta-2023-04-20" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/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@sha256:5ff2268d62e97bff2cde7d5815dd6ed5b47097566f13b8d0ca110b04b60e07ed" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2023-04-20" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cf1b5edb1b8bbb0003d80f5a12bb2886342826d2e1d9bd69d005dc6db59168c4
[INFO] running `Command { std: "docker" "start" "-a" "cf1b5edb1b8bbb0003d80f5a12bb2886342826d2e1d9bd69d005dc6db59168c4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cf1b5edb1b8bbb0003d80f5a12bb2886342826d2e1d9bd69d005dc6db59168c4", kill_on_drop: false }`
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[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling syn v1.0.84
[INFO] [stderr]    Compiling crossbeam-utils v0.8.6
[INFO] [stderr]    Compiling libc v0.2.112
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.6
[INFO] [stderr]    Compiling strsim v0.10.0
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling frunk_core v0.4.0
[INFO] [stderr]    Compiling ident_case v1.0.1
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]     Checking bytemuck v1.7.3
[INFO] [stderr]     Checking safe_arch v0.6.0
[INFO] [stderr]    Compiling quote v1.0.14
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling indexmap v1.8.0
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]     Checking rawpointer v0.2.1
[INFO] [stderr]     Checking matrixmultiply v0.3.2
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking approx v0.5.0
[INFO] [stderr]    Compiling nom v7.1.0
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking wide v0.7.3
[INFO] [stderr]     Checking crossbeam-channel v0.5.2
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]     Checking hashbrown v0.11.2
[INFO] [stderr]    Compiling paste v1.0.6
[INFO] [stderr]     Checking bytes v1.1.0
[INFO] [stderr]     Checking compare v0.1.0
[INFO] [stderr]     Checking bit-vec v0.6.3
[INFO] [stderr]     Checking fixedbitset v0.4.1
[INFO] [stderr]     Checking minimal-lexical v0.2.1
[INFO] [stderr]     Checking bit-matrix v0.6.1
[INFO] [stderr]     Checking simba v0.7.0
[INFO] [stderr]     Checking combine v4.6.2
[INFO] [stderr]     Checking petgraph v0.6.0
[INFO] [stderr]     Checking binary-heap-plus v0.4.1
[INFO] [stderr]     Checking itertools v0.9.0
[INFO] [stderr]     Checking ndarray v0.15.4
[INFO] [stderr]     Checking counter v0.5.2
[INFO] [stderr]     Checking arrayvec v0.7.2
[INFO] [stderr]    Compiling frunk_proc_macro_helpers v0.1.0
[INFO] [stderr]    Compiling darling_core v0.13.1
[INFO] [stderr]    Compiling frunk_proc_macros_impl v0.1.0
[INFO] [stderr]    Compiling frunk_derives v0.4.0
[INFO] [stderr]    Compiling nalgebra-macros v0.1.0
[INFO] [stderr]     Checking frunk_proc_macros v0.1.0
[INFO] [stderr]    Compiling darling_macro v0.13.1
[INFO] [stderr]     Checking frunk v0.4.0
[INFO] [stderr]    Compiling darling v0.13.1
[INFO] [stderr]    Compiling enumset_derive v0.5.5
[INFO] [stderr]     Checking nalgebra v0.30.1
[INFO] [stderr]     Checking enumset v1.0.8
[INFO] [stderr]  Documenting aoc2021 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking aoc2021 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(box_syntax)]
[INFO] [stdout]   |            ^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: replaced with `#[rustc_box]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(box_syntax)]
[INFO] [stdout]   |            ^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: replaced with `#[rustc_box]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0557`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `aoc2021`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2021 --crate-type lib --crate-name aoc2021 src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=e87c14763e1e3699 -L dependency=/opt/rustwide/target/debug/deps --extern arrayvec=/opt/rustwide/target/debug/deps/libarrayvec-06aa62afea35b94e.rmeta --extern binary_heap_plus=/opt/rustwide/target/debug/deps/libbinary_heap_plus-704ed9ac34f4eccd.rmeta --extern bit_matrix=/opt/rustwide/target/debug/deps/libbit_matrix-b1fd40f1f1bafcdc.rmeta --extern combine=/opt/rustwide/target/debug/deps/libcombine-9e3cdeaf4c1df01b.rmeta --extern counter=/opt/rustwide/target/debug/deps/libcounter-82cb94a0d92352c7.rmeta --extern enumset=/opt/rustwide/target/debug/deps/libenumset-9c00597075200fc1.rmeta --extern frunk=/opt/rustwide/target/debug/deps/libfrunk-3daf9975d1e5ab44.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-878b88b4202074c2.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-701e134f05ff346a.rmeta --extern nalgebra=/opt/rustwide/target/debug/deps/libnalgebra-6bffee223af477ee.rmeta --extern ndarray=/opt/rustwide/target/debug/deps/libndarray-8e92c963e033f1d3.rmeta --extern nom=/opt/rustwide/target/debug/deps/libnom-c2e02be9b608e197.rmeta --extern num_traits=/opt/rustwide/target/debug/deps/libnum_traits-988e2dfe91e328ad.rmeta --extern petgraph=/opt/rustwide/target/debug/deps/libpetgraph-398f8afcb5371a22.rmeta --extern rayon=/opt/rustwide/target/debug/deps/librayon-c623d32cb36d528b.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:42:47
[INFO] [stdout]    |
[INFO] [stdout] 42 |                         *zipper.focus_mut() = box Leaf(0);
[INFO] [stdout]    |                                               ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 42 |                         *zipper.focus_mut() = Box::new(Leaf(0));
[INFO] [stdout]    |                                               ~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:56:54
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = box Branch(box Leaf(l), box Leaf(r));
[INFO] [stdout]    |                                                      ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = box Branch(Box::new(Leaf(l)), box Leaf(r));
[INFO] [stdout]    |                                                      ~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:56:67
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = box Branch(box Leaf(l), box Leaf(r));
[INFO] [stdout]    |                                                                   ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = box Branch(box Leaf(l), Box::new(Leaf(r)));
[INFO] [stdout]    |                                                                   ~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:56:43
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = box Branch(box Leaf(l), box Leaf(r));
[INFO] [stdout]    |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 56 |                     *zipper.focus_mut() = Box::new(Branch(box Leaf(l), box Leaf(r)));
[INFO] [stdout]    |                                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:81:16
[INFO] [stdout]    |
[INFO] [stdout] 81 |         Number(box Branch(self.0, rhs.0)).reduce()
[INFO] [stdout]    |                ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 81 |         Number(Box::new(Branch(self.0, rhs.0))).reduce()
[INFO] [stdout]    |                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:90:18
[INFO] [stdout]    |
[INFO] [stdout] 90 |         .map(|n| box Leaf(n))
[INFO] [stdout]    |                  ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 90 |         .map(|n| Box::new(Leaf(n)))
[INFO] [stdout]    |                  ~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/mod.rs:97:31
[INFO] [stdout]    |
[INFO] [stdout] 97 |                 .map(|(l, r)| box Branch(l, r)),
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 97 |                 .map(|(l, r)| Box::new(Branch(l, r))),
[INFO] [stdout]    |                               ~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/tree.rs:89:34
[INFO] [stdout]    |
[INFO] [stdout] 89 |                 (Left, right) => box Branch(focus, right),
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 89 |                 (Left, right) => Box::new(Branch(focus, right)),
[INFO] [stdout]    |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]   --> src/day_18/tree.rs:90:34
[INFO] [stdout]    |
[INFO] [stdout] 90 |                 (Right, left) => box Branch(left, focus),
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]    |
[INFO] [stdout] 90 |                 (Right, left) => Box::new(Branch(left, focus)),
[INFO] [stdout]    |                                  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:172:52
[INFO] [stdout]     |
[INFO] [stdout] 172 |                     Some((Left, right)) => focus = box Branch(focus, right),
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 172 |                     Some((Left, right)) => focus = Box::new(Branch(focus, right)),
[INFO] [stdout]     |                                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:174:33
[INFO] [stdout]     |
[INFO] [stdout] 174 |                         focus = box Branch(left, focus);
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 174 |                         focus = Box::new(Branch(left, focus));
[INFO] [stdout]     |                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:199:52
[INFO] [stdout]     |
[INFO] [stdout] 199 |                     Some((Right, left)) => focus = box Branch(left, focus),
[INFO] [stdout]     |                                                    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 199 |                     Some((Right, left)) => focus = Box::new(Branch(left, focus)),
[INFO] [stdout]     |                                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:201:33
[INFO] [stdout]     |
[INFO] [stdout] 201 |                         focus = box Branch(focus, right);
[INFO] [stdout]     |                                 ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 201 |                         focus = Box::new(Branch(focus, right));
[INFO] [stdout]     |                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:270:31
[INFO] [stdout]     |
[INFO] [stdout] 270 |                 Left => ret = box Branch(ret, tree),
[INFO] [stdout]     |                               ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 270 |                 Left => ret = Box::new(Branch(ret, tree)),
[INFO] [stdout]     |                               ~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: `box_syntax` has been removed
[INFO] [stdout]    --> src/day_18/tree.rs:271:32
[INFO] [stdout]     |
[INFO] [stdout] 271 |                 Right => ret = box Branch(tree, ret),
[INFO] [stdout]     |                                ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: use `Box::new()` instead
[INFO] [stdout]     |
[INFO] [stdout] 271 |                 Right => ret = Box::new(Branch(tree, ret)),
[INFO] [stdout]     |                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_patterns)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(box_syntax)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(hash_drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(once_cell)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(step_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:3:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(hash_drain_filter)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(once_cell)]
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(step_trait)]
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `once_cell` has been stable since 1.70.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(once_cell)]
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 24 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `aoc2021` (lib) due to 25 previous errors; 1 warning emitted
[INFO] running `Command { std: "docker" "inspect" "6af565fa1703282525b2d5a600742085682b899bf2c936a85324a5cf77c1d23c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6af565fa1703282525b2d5a600742085682b899bf2c936a85324a5cf77c1d23c", kill_on_drop: false }`
[INFO] [stdout] 6af565fa1703282525b2d5a600742085682b899bf2c936a85324a5cf77c1d23c
