[INFO] fetching crate mcio 0.3.1...
[INFO] documenting mcio-0.3.1 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate mcio 0.3.1 into /workspace/builds/worker-31/source
[INFO] validating manifest of crates.io crate mcio 0.3.1 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mcio 0.3.1
[INFO] finished tweaking crates.io crate mcio 0.3.1
[INFO] tweaked toml for crates.io crate mcio 0.3.1 written to /workspace/builds/worker-31/source/Cargo.toml
[INFO] crate crates.io crate mcio 0.3.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e2321bae5af8cfdf8e416e1edffc197c8170ae096746b65c3c77e010ee7f05cd
[INFO] running `Command { std: "docker" "start" "-a" "e2321bae5af8cfdf8e416e1edffc197c8170ae096746b65c3c77e010ee7f05cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e2321bae5af8cfdf8e416e1edffc197c8170ae096746b65c3c77e010ee7f05cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2321bae5af8cfdf8e416e1edffc197c8170ae096746b65c3c77e010ee7f05cd", kill_on_drop: false }`
[INFO] [stdout] e2321bae5af8cfdf8e416e1edffc197c8170ae096746b65c3c77e010ee7f05cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 76f188c5d6265d6db49c4f38b8448630b1f81f89bbf4b855518b224787d1f46e
[INFO] running `Command { std: "docker" "start" "-a" "76f188c5d6265d6db49c4f38b8448630b1f81f89bbf4b855518b224787d1f46e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.69
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking futures v0.1.29
[INFO] [stderr]    Compiling winapi-build v0.1.1
[INFO] [stderr]     Checking fnv v1.0.6
[INFO] [stderr]    Compiling proc-macro2 v1.0.10
[INFO] [stderr]    Compiling cc v1.0.50
[INFO] [stderr]     Checking winapi v0.2.8
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling backtrace v0.2.3
[INFO] [stderr]     Checking smallvec v1.3.0
[INFO] [stderr]     Checking rustc-demangle v0.1.16
[INFO] [stderr]    Compiling ryu v1.0.3
[INFO] [stderr]    Compiling serde v1.0.106
[INFO] [stderr]     Checking match_cfg v0.1.0
[INFO] [stderr]     Checking linked-hash-map v0.5.2
[INFO] [stderr]     Checking itoa v0.4.5
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]    Compiling dbghelp-sys v0.2.0
[INFO] [stderr]    Compiling kernel32-sys v0.2.2
[INFO] [stderr]     Checking lru-cache v0.1.2
[INFO] [stderr]     Checking unicode-normalization v0.1.12
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling backtrace-sys v0.1.35
[INFO] [stderr]    Compiling quote v1.0.3
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking parking_lot_core v0.6.2
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking socket2 v0.3.12
[INFO] [stderr]     Checking hostname v0.3.1
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking resolv-conf v0.6.3
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking tokio-sync v0.1.8
[INFO] [stderr]     Checking parking_lot v0.9.0
[INFO] [stderr]     Checking mio v0.6.21
[INFO] [stderr]     Checking tokio-executor v0.1.10
[INFO] [stderr]     Checking crossbeam-queue v0.2.1
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]     Checking tokio-timer v0.2.13
[INFO] [stderr]     Checking tokio-current-thread v0.1.7
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking error-chain v0.1.12
[INFO] [stderr]     Checking tokio-threadpool v0.1.18
[INFO] [stderr]     Checking tokio-reactor v0.1.12
[INFO] [stderr]     Checking tokio-codec v0.1.2
[INFO] [stderr]     Checking tokio-fs v0.1.7
[INFO] [stderr]     Checking tokio-tcp v0.1.4
[INFO] [stderr]     Checking tokio-udp v0.1.6
[INFO] [stderr]     Checking tokio-uds v0.2.6
[INFO] [stderr]     Checking trust-dns-proto v0.4.3
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]    Compiling serde_derive v1.0.106
[INFO] [stderr]     Checking trust-dns-resolver v0.9.1
[INFO] [stderr]     Checking serde_json v1.0.51
[INFO] [stderr]  Documenting mcio v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(external_doc)]
[INFO] [stdout]   |            ^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: use #[doc = include_str!("filename")] instead, which handles macro invocations
[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(external_doc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `mcio`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name mcio 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 serde=/opt/rustwide/target/debug/deps/libserde-628542da47eceb2b.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-80ca5f77e5d78463.rmeta --extern trust_dns_resolver=/opt/rustwide/target/debug/deps/libtrust_dns_resolver-486faf8c2b67f1fa.rmeta --cap-lints=warn --crate-version 0.3.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "76f188c5d6265d6db49c4f38b8448630b1f81f89bbf4b855518b224787d1f46e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "76f188c5d6265d6db49c4f38b8448630b1f81f89bbf4b855518b224787d1f46e", kill_on_drop: false }`
[INFO] [stdout] 76f188c5d6265d6db49c4f38b8448630b1f81f89bbf4b855518b224787d1f46e
