[INFO] fetching crate eng-wasm 0.1.7...
[INFO] documenting eng-wasm-0.1.7 against 1.76.0 for beta-1.77-rustdoc-1
[INFO] extracting crate eng-wasm 0.1.7 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate eng-wasm 0.1.7 on toolchain 1.76.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate eng-wasm 0.1.7
[INFO] finished tweaking crates.io crate eng-wasm 0.1.7
[INFO] tweaked toml for crates.io crate eng-wasm 0.1.7 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.76.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded eng-pwasm-abi v0.3.2
[INFO] [stderr]   Downloaded static_assertions v0.2.5
[INFO] [stderr]   Downloaded fixed-hash v0.3.2
[INFO] [stderr]   Downloaded uint v0.6.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 9538cbc2e106a4290fdf2134e1f7df0a75df022e1921bd1ca18327052a1b9554
[INFO] running `Command { std: "docker" "start" "-a" "9538cbc2e106a4290fdf2134e1f7df0a75df022e1921bd1ca18327052a1b9554", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9538cbc2e106a4290fdf2134e1f7df0a75df022e1921bd1ca18327052a1b9554", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9538cbc2e106a4290fdf2134e1f7df0a75df022e1921bd1ca18327052a1b9554", kill_on_drop: false }`
[INFO] [stdout] 9538cbc2e106a4290fdf2134e1f7df0a75df022e1921bd1ca18327052a1b9554
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8f6fc97062b6e5250df0caf4606491de78a1650f6fa3db810992e2fedfb19b6f
[INFO] running `Command { std: "docker" "start" "-a" "8f6fc97062b6e5250df0caf4606491de78a1650f6fa3db810992e2fedfb19b6f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]    Compiling crunchy v0.2.2
[INFO] [stderr]    Compiling serde v1.0.196
[INFO] [stderr]     Checking static_assertions v0.2.5
[INFO] [stderr]     Checking rustc-hex v2.1.0
[INFO] [stderr]     Checking byteorder v1.5.0
[INFO] [stderr]     Checking fixed-hash v0.3.2
[INFO] [stderr]     Checking uint v0.6.1
[INFO] [stderr]    Compiling quote v1.0.35
[INFO] [stderr]    Compiling syn v2.0.48
[INFO] [stderr]    Compiling serde_derive v1.0.196
[INFO] [stderr]     Checking eng-pwasm-abi v0.3.2
[INFO] [stderr]     Checking serde_json v1.0.113
[INFO] [stderr]  Documenting eng-wasm v0.1.7 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(slice_concat_trait)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `eng-wasm`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/rustup-home/toolchains/1.76.0-x86_64-unknown-linux-gnu/bin/rustdoc --crate-type lib --crate-name eng_wasm src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=7366970233745ac4 -L dependency=/opt/rustwide/target/debug/deps --extern eng_pwasm_abi=/opt/rustwide/target/debug/deps/libeng_pwasm_abi-c16128e684095b9d.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-e7de17d8b0ed363b.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-10ff0d46645e8da4.rmeta --cap-lints=warn --crate-version 0.1.7` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "8f6fc97062b6e5250df0caf4606491de78a1650f6fa3db810992e2fedfb19b6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8f6fc97062b6e5250df0caf4606491de78a1650f6fa3db810992e2fedfb19b6f", kill_on_drop: false }`
[INFO] [stdout] 8f6fc97062b6e5250df0caf4606491de78a1650f6fa3db810992e2fedfb19b6f
