[INFO] fetching crate loader 0.2.1...
[INFO] documenting loader-0.2.1 against 1.76.0 for beta-1.77-rustdoc-1
[INFO] extracting crate loader 0.2.1 into /workspace/builds/worker-2-tc1/source
[INFO] validating manifest of crates.io crate loader 0.2.1 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 loader 0.2.1
[INFO] finished tweaking crates.io crate loader 0.2.1
[INFO] tweaked toml for crates.io crate loader 0.2.1 written to /workspace/builds/worker-2-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] 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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.76.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4bbd0f9cf311aa39e9d99b5ed7131a151686c42a08fee8e7183ff501854d5a75
[INFO] running `Command { std: "docker" "start" "-a" "4bbd0f9cf311aa39e9d99b5ed7131a151686c42a08fee8e7183ff501854d5a75", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4bbd0f9cf311aa39e9d99b5ed7131a151686c42a08fee8e7183ff501854d5a75", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4bbd0f9cf311aa39e9d99b5ed7131a151686c42a08fee8e7183ff501854d5a75", kill_on_drop: false }`
[INFO] [stdout] 4bbd0f9cf311aa39e9d99b5ed7131a151686c42a08fee8e7183ff501854d5a75
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/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] aa4f7853ce26a71b02e9a77a5f6703b100d789f5170544fa696e57e07b4e358e
[INFO] running `Command { std: "docker" "start" "-a" "aa4f7853ce26a71b02e9a77a5f6703b100d789f5170544fa696e57e07b4e358e", kill_on_drop: false }`
[INFO] [stderr]  Documenting loader v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:33
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![cfg_attr(feature = "unsize", feature(unsize))]
[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:2:33
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![cfg_attr(feature = "unsize", feature(coerce_unsized))]
[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:3:36
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![cfg_attr(feature = "fn_traits", 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:4:36
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(feature = "fn_traits", feature(fn_traits))]
[INFO] [stdout]   |                                    ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `loader`
[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 --edition=2021 --crate-type lib --crate-name loader src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="fn_traits"' --cfg 'feature="unsize"' --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=428949eac1dd54df -L dependency=/opt/rustwide/target/debug/deps --extern libc=/opt/rustwide/target/debug/deps/liblibc-90dcd21b8f97cd2f.rmeta --cap-lints=warn --crate-version 0.2.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "aa4f7853ce26a71b02e9a77a5f6703b100d789f5170544fa696e57e07b4e358e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aa4f7853ce26a71b02e9a77a5f6703b100d789f5170544fa696e57e07b4e358e", kill_on_drop: false }`
[INFO] [stdout] aa4f7853ce26a71b02e9a77a5f6703b100d789f5170544fa696e57e07b4e358e
