[INFO] fetching crate kf-protocol-core 0.1.2...
[INFO] documenting kf-protocol-core-0.1.2 against beta-2021-08-01 for beta-1.55-rustdoc-1
[INFO] extracting crate kf-protocol-core 0.1.2 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate kf-protocol-core 0.1.2 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate kf-protocol-core 0.1.2
[INFO] finished tweaking crates.io crate kf-protocol-core 0.1.2
[INFO] tweaked toml for crates.io crate kf-protocol-core 0.1.2 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 287460f7fb5064c836975b195c072f3254999f065ab7d0ab08c57d4fe545ef9f
[INFO] running `Command { std: "docker" "start" "-a" "287460f7fb5064c836975b195c072f3254999f065ab7d0ab08c57d4fe545ef9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "287460f7fb5064c836975b195c072f3254999f065ab7d0ab08c57d4fe545ef9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "287460f7fb5064c836975b195c072f3254999f065ab7d0ab08c57d4fe545ef9f", kill_on_drop: false }`
[INFO] [stdout] 287460f7fb5064c836975b195c072f3254999f065ab7d0ab08c57d4fe545ef9f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b1a0cb12753107d65b3b42e7e08d49b573e7f3729869038fab3606c660a729d6
[INFO] running `Command { std: "docker" "start" "-a" "b1a0cb12753107d65b3b42e7e08d49b573e7f3729869038fab3606c660a729d6", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]  Documenting kf-protocol-core v0.1.2 (/opt/rustwide/workdir)
[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(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 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 `kf-protocol-core`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name kf_protocol_core src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern bytes=/opt/rustwide/target/debug/deps/libbytes-be6cb9a7be86933c.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-be8c314c6d97e413.rmeta --extern num_derive=/opt/rustwide/target/debug/deps/libnum_derive-6ba2d296a3e294f9.so --extern num_traits=/opt/rustwide/target/debug/deps/libnum_traits-397d8ff81ee88563.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-8914c1b130a4d038.rmeta --cap-lints=warn --crate-version 0.1.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "b1a0cb12753107d65b3b42e7e08d49b573e7f3729869038fab3606c660a729d6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b1a0cb12753107d65b3b42e7e08d49b573e7f3729869038fab3606c660a729d6", kill_on_drop: false }`
[INFO] [stdout] b1a0cb12753107d65b3b42e7e08d49b573e7f3729869038fab3606c660a729d6
