[INFO] fetching crate ngram_iter 0.1.0...
[INFO] testing ngram_iter-0.1.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate ngram_iter 0.1.0 into /workspace/builds/worker-1-tc1/source
[INFO] started tweaking crates.io crate ngram_iter 0.1.0
[INFO] finished tweaking crates.io crate ngram_iter 0.1.0
[INFO] tweaked toml for crates.io crate ngram_iter 0.1.0 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate ngram_iter 0.1.0 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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] bbec9a9d42eabfc6e49b8adccaed22a512a159799d6c42ed931842006ae8d3b4
[INFO] running `Command { std: "docker" "start" "-a" "bbec9a9d42eabfc6e49b8adccaed22a512a159799d6c42ed931842006ae8d3b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bbec9a9d42eabfc6e49b8adccaed22a512a159799d6c42ed931842006ae8d3b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bbec9a9d42eabfc6e49b8adccaed22a512a159799d6c42ed931842006ae8d3b4", kill_on_drop: false }`
[INFO] [stdout] bbec9a9d42eabfc6e49b8adccaed22a512a159799d6c42ed931842006ae8d3b4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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] b6586119a0b67ebafcf8415c5444315ef5d9b71eb2f6f6fbcecdecc52edc3e6a
[INFO] running `Command { std: "docker" "start" "-a" "b6586119a0b67ebafcf8415c5444315ef5d9b71eb2f6f6fbcecdecc52edc3e6a", kill_on_drop: false }`
[INFO] [stderr]    Compiling ngram_iter v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(maybe_uninit_uninit_array)]
[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:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(maybe_uninit_array_assume_init)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `maybe_uninit_uninit_array`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(maybe_uninit_uninit_array)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no function or associated item named `uninit_array` found for union `MaybeUninit` in the current scope
[INFO] [stdout]   --> src/iter/mod.rs:53:57
[INFO] [stdout]    |
[INFO] [stdout] 53 |         let mut out: [MaybeUninit<T>; N] = MaybeUninit::uninit_array();
[INFO] [stdout]    |                                                         ^^^^^^^^^^^^ function or associated item not found in `MaybeUninit<_>`
[INFO] [stdout]    |
[INFO] [stdout] note: if you're trying to build a new `MaybeUninit<_>` consider using one of the following associated functions:
[INFO] [stdout]       MaybeUninit::<T>::new
[INFO] [stdout]       MaybeUninit::<T>::uninit
[INFO] [stdout]       MaybeUninit::<T>::zeroed
[INFO] [stdout]   --> /rustc/1159e78c4747b02ef996e55082b704c09b970588/library/core/src/mem/maybe_uninit.rs:307:5
[INFO] [stdout] help: there is an associated function `uninit` with a similar name
[INFO] [stdout]    |
[INFO] [stdout] 53 -         let mut out: [MaybeUninit<T>; N] = MaybeUninit::uninit_array();
[INFO] [stdout] 53 +         let mut out: [MaybeUninit<T>; N] = MaybeUninit::uninit();
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ngram_iter` (lib) due to 4 previous errors
[INFO] running `Command { std: "docker" "inspect" "b6586119a0b67ebafcf8415c5444315ef5d9b71eb2f6f6fbcecdecc52edc3e6a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b6586119a0b67ebafcf8415c5444315ef5d9b71eb2f6f6fbcecdecc52edc3e6a", kill_on_drop: false }`
[INFO] [stdout] b6586119a0b67ebafcf8415c5444315ef5d9b71eb2f6f6fbcecdecc52edc3e6a
