[INFO] fetching crate delay_line 0.1.2...
[INFO] testing delay_line-0.1.2 against 1.90.0 for beta-1.91-3
[INFO] extracting crate delay_line 0.1.2 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate delay_line 0.1.2
[INFO] finished tweaking crates.io crate delay_line 0.1.2
[INFO] tweaked toml for crates.io crate delay_line 0.1.2 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate delay_line 0.1.2 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate delay_line 0.1.2 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" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 401846547f4ef853331b4297bc3b80584e55fa085cadb23809b35cb8af329d29
[INFO] running `Command { std: "docker" "start" "-a" "401846547f4ef853331b4297bc3b80584e55fa085cadb23809b35cb8af329d29", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "401846547f4ef853331b4297bc3b80584e55fa085cadb23809b35cb8af329d29", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "401846547f4ef853331b4297bc3b80584e55fa085cadb23809b35cb8af329d29", kill_on_drop: false }`
[INFO] [stdout] 401846547f4ef853331b4297bc3b80584e55fa085cadb23809b35cb8af329d29
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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=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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 26d0fa349e44d345a45f12c59e87b266206b840140676ccd91fca35ca151fea7
[INFO] running `Command { std: "docker" "start" "-a" "26d0fa349e44d345a45f12c59e87b266206b840140676ccd91fca35ca151fea7", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.19
[INFO] [stderr]    Compiling delay_line v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(allocator_api)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(unboxed_closures)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(fn_traits)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![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 stable release channel
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(vec_push_within_capacity)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(vec_split_at_spare)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(inherent_associated_types)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(slice_pattern)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(decl_macro)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `inherent_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:8:12
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(inherent_associated_types)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: see issue #8995 <https://github.com/rust-lang/rust/issues/8995> for more information
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[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:5:12
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(let_chains)]
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(stable_features)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0220]: associated type `Output` not found for `DelayLine<T, A>` in the current scope
[INFO] [stdout]     --> src/lib.rs:1047:68
[INFO] [stdout]      |
[INFO] [stdout]   76 | pub struct DelayLine<T, A = Global>
[INFO] [stdout]      | ----------------------------------- associated type `Output` not found for this struct
[INFO] [stdout] ...
[INFO] [stdout] 1047 |     extern "rust-call" fn call_once(mut self, (x,): (T,)) -> Self::Output
[INFO] [stdout]      |                                                                    ^^^^^^ associated item not found in `DelayLine<T, A>`
[INFO] [stdout]      |
[INFO] [stdout]      = note: the associated type was found for
[INFO] [stdout]              
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0220]: associated type `Output` not found for `DelayLine<T, A>` in the current scope
[INFO] [stdout]     --> src/lib.rs:1056:68
[INFO] [stdout]      |
[INFO] [stdout]   76 | pub struct DelayLine<T, A = Global>
[INFO] [stdout]      | ----------------------------------- associated type `Output` not found for this struct
[INFO] [stdout] ...
[INFO] [stdout] 1056 |     extern "rust-call" fn call_mut(&mut self, (x,): (T,)) -> Self::Output
[INFO] [stdout]      |                                                                    ^^^^^^ associated item not found in `DelayLine<T, A>`
[INFO] [stdout]      |
[INFO] [stdout]      = note: the associated type was found for
[INFO] [stdout]              
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0220, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0220`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `delay_line` (lib) due to 11 previous errors; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "26d0fa349e44d345a45f12c59e87b266206b840140676ccd91fca35ca151fea7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "26d0fa349e44d345a45f12c59e87b266206b840140676ccd91fca35ca151fea7", kill_on_drop: false }`
[INFO] [stdout] 26d0fa349e44d345a45f12c59e87b266206b840140676ccd91fca35ca151fea7