[INFO] fetching crate metacomplete 2.0.1...
[INFO] testing metacomplete-2.0.1 against beta-2025-10-28 for beta-1.92-2
[INFO] extracting crate metacomplete 2.0.1 into /workspace/builds/worker-7-tc2/source
[INFO] removed /workspace/builds/worker-7-tc2/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate metacomplete 2.0.1
[INFO] finished tweaking crates.io crate metacomplete 2.0.1
[INFO] tweaked toml for crates.io crate metacomplete 2.0.1 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate metacomplete 2.0.1 on toolchain beta-2025-10-28
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2025-10-28" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate metacomplete 2.0.1 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-2025-10-28" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-10-28" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4ab6c62c886b9c0762399bd9810ab65b14d698df8845fdec016f860a75bb9cdc
[INFO] running `Command { std: "docker" "start" "-a" "4ab6c62c886b9c0762399bd9810ab65b14d698df8845fdec016f860a75bb9cdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4ab6c62c886b9c0762399bd9810ab65b14d698df8845fdec016f860a75bb9cdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ab6c62c886b9c0762399bd9810ab65b14d698df8845fdec016f860a75bb9cdc", kill_on_drop: false }`
[INFO] [stdout] 4ab6c62c886b9c0762399bd9810ab65b14d698df8845fdec016f860a75bb9cdc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2025-10-28" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 256d2d21a60f533cb37c382e3490b090513efb665540932e4cedf34a49275d42
[INFO] running `Command { std: "docker" "start" "-a" "256d2d21a60f533cb37c382e3490b090513efb665540932e4cedf34a49275d42", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling never-say-never v6.6.666
[INFO] [stderr]    Compiling ppv-lite86 v0.2.17
[INFO] [stderr]    Compiling fst v0.4.7
[INFO] [stderr]    Compiling once_cell v1.19.0
[INFO] [stderr]    Compiling stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling pin-project-lite v0.2.16
[INFO] [stderr]    Compiling debug_print v1.0.0
[INFO] [stderr]    Compiling slab v0.4.9
[INFO] [stderr]    Compiling syn v2.0.48
[INFO] [stderr]    Compiling higher-kinded-types v0.1.1
[INFO] [stderr]    Compiling polonius-the-crab v0.4.1
[INFO] [stderr]    Compiling tracing-core v0.1.33
[INFO] [stderr]    Compiling metacomplete_ptrie v0.7.0
[INFO] [stderr]    Compiling getrandom v0.2.11
[INFO] [stderr]    Compiling rand_core v0.6.4
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling synstructure v0.13.0
[INFO] [stderr]    Compiling tracing-attributes v0.1.28
[INFO] [stderr]    Compiling derive-new v0.6.0
[INFO] [stderr]    Compiling zerofrom-derive v0.1.3
[INFO] [stderr]    Compiling yoke-derive v0.7.3
[INFO] [stderr]    Compiling tracing v0.1.41
[INFO] [stderr]    Compiling zerofrom v0.1.3
[INFO] [stderr]    Compiling yoke v0.7.3
[INFO] [stderr]    Compiling metacomplete v2.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error: let chains are only allowed in Rust 2024 or later
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:534:20
[INFO] [stdout]     |
[INFO] [stdout] 534 |                 if let Some(k) = ps.sets.get(&b)
[INFO] [stdout]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: let chains are only allowed in Rust 2024 or later
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:562:24
[INFO] [stdout]     |
[INFO] [stdout] 562 |                     if let Some(new) = ps.sets.get(&t)
[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(closure_lifetime_binder)]
[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(let_chains)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `let_chains` has been stable since `1.88.0` and no longer requires an attribute to enable
[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(associated_type_defaults)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BinaryHeap`, `Borrow`, `RwLock`, and `hash_map`
[INFO] [stdout]   --> src/strprox/prefix/meta/mod.rs:2:14
[INFO] [stdout]    |
[INFO] [stdout]  2 |     borrow::{Borrow, Cow},
[INFO] [stdout]    |              ^^^^^^
[INFO] [stdout] ...
[INFO] [stdout]  6 |         hash_map, BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet,
[INFO] [stdout]    |         ^^^^^^^^                      ^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 12 |     sync::{Mutex, RwLock},
[INFO] [stdout]    |                   ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `edit_distance`
[INFO] [stdout]   --> src/strprox/prefix/meta/mod.rs:18:25
[INFO] [stdout]    |
[INFO] [stdout] 18 |     levenshtein::{self, edit_distance, edit_distance_chars},
[INFO] [stdout]    |                         ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `trace`
[INFO] [stdout]   --> src/strprox/prefix/meta/mod.rs:21:31
[INFO] [stdout]    |
[INFO] [stdout] 21 | use tracing::{debug, enabled, trace, Level};
[INFO] [stdout]    |                               ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `debug_print::debug_println`
[INFO] [stdout]   --> src/strprox/prefix/meta/mod.rs:23:5
[INFO] [stdout]    |
[INFO] [stdout] 23 | use debug_print::debug_println;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `polonius_return` and `polonius`
[INFO] [stdout]   --> src/strprox/prefix/meta/mod.rs:24:25
[INFO] [stdout]    |
[INFO] [stdout] 24 | use polonius_the_crab::{polonius, polonius_return};
[INFO] [stdout]    |                         ^^^^^^^^  ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused label
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:500:17
[INFO] [stdout]     |
[INFO] [stdout] 500 |                 'ped: for m in set {
[INFO] [stdout]     |                 ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_labels)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Standard`
[INFO] [stdout]    --> src/levenshtein/mod.rs:126:45
[INFO] [stdout]     |
[INFO] [stdout] 126 |     use rand::distributions::{Alphanumeric, Standard};
[INFO] [stdout]     |                                             ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `let_chains` has been stable since 1.88.0 and no longer requires an attribute to enable
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(let_chains)]
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `io::Read`
[INFO] [stdout]  --> src/strprox/prefix/meta/mod.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 |     io::Read,
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Write`
[INFO] [stdout]  --> src/strprox/prefix/meta/mod.rs:8:20
[INFO] [stdout]   |
[INFO] [stdout] 8 |     fmt::{Display, Write},
[INFO] [stdout]   |                    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `state`
[INFO] [stdout]   --> src/strprox/prefix/fst/mod.rs:31:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |         state: &mut (),
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_state`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ed`
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:499:24
[INFO] [stdout]     |
[INFO] [stdout] 499 |             for (_ix, (ed, set)) in sorted.into_iter().enumerate() {
[INFO] [stdout]     |                        ^^ help: if this is intentional, prefix it with an underscore: `_ed`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num_entries`
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:519:9
[INFO] [stdout]     |
[INFO] [stdout] 519 |         num_entries: usize,
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_num_entries`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `n2`
[INFO] [stdout]    --> src/strprox/prefix/meta/mod.rs:854:85
[INFO] [stdout]     |
[INFO] [stdout] 854 |                     self.traverse_inverted_index(m1.clone(), depth, character, |id, n2| {
[INFO] [stdout]     |                                                                                     ^^ help: if this is intentional, prefix it with an underscore: `_n2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `metacomplete` (lib) due to 5 previous errors; 14 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "256d2d21a60f533cb37c382e3490b090513efb665540932e4cedf34a49275d42", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "256d2d21a60f533cb37c382e3490b090513efb665540932e4cedf34a49275d42", kill_on_drop: false }`
[INFO] [stdout] 256d2d21a60f533cb37c382e3490b090513efb665540932e4cedf34a49275d42
