[INFO] fetching crate muta-protocol 0.1.0-alpha.1...
[INFO] documenting muta-protocol-0.1.0-alpha.1 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate muta-protocol 0.1.0-alpha.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate muta-protocol 0.1.0-alpha.1 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate muta-protocol 0.1.0-alpha.1
[INFO] finished tweaking crates.io crate muta-protocol 0.1.0-alpha.1
[INFO] tweaked toml for crates.io crate muta-protocol 0.1.0-alpha.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e95ae9cf0dfa2037f65e9b70d171c328495e6f94e9b1f97d12fcdd622fa28870
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e95ae9cf0dfa2037f65e9b70d171c328495e6f94e9b1f97d12fcdd622fa28870", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e95ae9cf0dfa2037f65e9b70d171c328495e6f94e9b1f97d12fcdd622fa28870", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e95ae9cf0dfa2037f65e9b70d171c328495e6f94e9b1f97d12fcdd622fa28870", kill_on_drop: false }`
[INFO] [stdout] e95ae9cf0dfa2037f65e9b70d171c328495e6f94e9b1f97d12fcdd622fa28870
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] da3878480bdfad5a17b63149eac78b4fdc6e96c9bdf997cdabc4aaefdb1bff80
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "da3878480bdfad5a17b63149eac78b4fdc6e96c9bdf997cdabc4aaefdb1bff80", 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] [stderr]    Compiling syn v1.0.45
[INFO] [stderr]    Compiling serde v1.0.117
[INFO] [stderr]     Checking rustc-hex v2.1.0
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling crunchy v0.2.2
[INFO] [stderr]    Compiling heapsize v0.4.2
[INFO] [stderr]    Compiling crunchy v0.1.6
[INFO] [stderr]    Compiling pin-project-internal v0.4.27
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling proc-macro-nested v0.1.6
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling anyhow v1.0.33
[INFO] [stderr]     Checking futures-core v0.3.6
[INFO] [stderr]     Checking futures-sink v0.3.6
[INFO] [stderr]     Checking once_cell v1.4.1
[INFO] [stderr]     Checking futures-io v0.3.6
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking slab v0.4.2
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking bytes v0.5.6
[INFO] [stderr]     Checking hashbrown v0.3.1
[INFO] [stderr]     Checking creep v0.1.1
[INFO] [stderr]     Checking hex v0.3.2
[INFO] [stderr]     Checking json v0.12.4
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]     Checking rlp v0.4.6
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]     Checking futures-channel v0.3.6
[INFO] [stderr]     Checking futures-task v0.3.6
[INFO] [stderr]     Checking lock_api v0.2.0
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]     Checking memchr v2.3.3
[INFO] [stderr]     Checking impl-rlp v0.2.1
[INFO] [stderr]     Checking tiny-keccak v1.5.0
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]     Checking fixed-hash v0.2.5
[INFO] [stderr]     Checking uint v0.4.1
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking hasher v0.1.3
[INFO] [stderr]    Compiling parking_lot_core v0.5.0
[INFO] [stderr]    Compiling parking_lot v0.8.0
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking num-bigint v0.2.6
[INFO] [stderr]     Checking fixed-hash v0.5.2
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]    Compiling serde_derive v1.0.117
[INFO] [stderr]    Compiling futures-macro v0.3.6
[INFO] [stderr]    Compiling prost-derive v0.6.1
[INFO] [stderr]    Compiling async-trait v0.1.41
[INFO] [stderr]     Checking prost v0.6.1
[INFO] [stderr]     Checking pin-project v0.4.27
[INFO] [stderr]     Checking futures-util v0.3.6
[INFO] [stderr]     Checking futures-executor v0.3.6
[INFO] [stderr]     Checking futures v0.3.6
[INFO] [stderr]     Checking ethereum-types-serialize v0.2.2
[INFO] [stderr]     Checking impl-serde v0.2.3
[INFO] [stderr]     Checking bincode v1.3.1
[INFO] [stderr]     Checking serde_json v1.0.59
[INFO] [stderr]     Checking ethbloom v0.5.3
[INFO] [stderr]     Checking ethbloom v0.8.1
[INFO] [stderr]     Checking ethereum-types v0.4.2
[INFO] [stderr]     Checking rlp v0.3.0
[INFO] [stderr]     Checking cita_trie v2.0.0
[INFO] [stderr]  Documenting muta-protocol v0.1.0-alpha.1 (/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(test)]
[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 `muta-protocol`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name muta_protocol 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 async_trait=/opt/rustwide/target/debug/deps/libasync_trait-3f30cba0253d2948.so --extern bincode=/opt/rustwide/target/debug/deps/libbincode-2f7fe994cd943817.rmeta --extern byteorder=/opt/rustwide/target/debug/deps/libbyteorder-c28f5fd38aa58f5e.rmeta --extern bytes=/opt/rustwide/target/debug/deps/libbytes-060d9d2e342fea55.rmeta --extern cita_trie=/opt/rustwide/target/debug/deps/libcita_trie-6ba152be1e42a600.rmeta --extern creep=/opt/rustwide/target/debug/deps/libcreep-ef7ffa66f8f08cf9.rmeta --extern derive_more=/opt/rustwide/target/debug/deps/libderive_more-779f5eca832dbce1.so --extern ethbloom=/opt/rustwide/target/debug/deps/libethbloom-537f431ba240c0f6.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-8df2e33c95419672.rmeta --extern hasher=/opt/rustwide/target/debug/deps/libhasher-9dba406410696a97.rmeta --extern hex=/opt/rustwide/target/debug/deps/libhex-839d4d25d8b13775.rmeta --extern json=/opt/rustwide/target/debug/deps/libjson-ae9d7700866fab35.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-72923b2d9aa06af7.rmeta --extern num_bigint=/opt/rustwide/target/debug/deps/libnum_bigint-efb761a1d1d8003a.rmeta --extern prost=/opt/rustwide/target/debug/deps/libprost-25e90b152f363e87.rmeta --extern rlp=/opt/rustwide/target/debug/deps/librlp-fec3861d25acd12d.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-176c2a57aac554ca.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-b93bd3e800557f06.rmeta --cap-lints=warn --crate-version 0.1.0-alpha.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "da3878480bdfad5a17b63149eac78b4fdc6e96c9bdf997cdabc4aaefdb1bff80", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "da3878480bdfad5a17b63149eac78b4fdc6e96c9bdf997cdabc4aaefdb1bff80", kill_on_drop: false }`
[INFO] [stdout] da3878480bdfad5a17b63149eac78b4fdc6e96c9bdf997cdabc4aaefdb1bff80
