[INFO] fetching crate mech-server 0.0.4...
[INFO] documenting mech-server-0.0.4 against beta-2021-08-01 for beta-1.55-rustdoc-1
[INFO] extracting crate mech-server 0.0.4 into /workspace/builds/worker-108/source
[INFO] validating manifest of crates.io crate mech-server 0.0.4 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 mech-server 0.0.4
[INFO] finished tweaking crates.io crate mech-server 0.0.4
[INFO] tweaked toml for crates.io crate mech-server 0.0.4 written to /workspace/builds/worker-108/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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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] 929392c6ef37b42723495dc14f6a596531c784e6a8837633ab3f017733f2b387
[INFO] running `Command { std: "docker" "start" "-a" "929392c6ef37b42723495dc14f6a596531c784e6a8837633ab3f017733f2b387", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "929392c6ef37b42723495dc14f6a596531c784e6a8837633ab3f017733f2b387", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "929392c6ef37b42723495dc14f6a596531c784e6a8837633ab3f017733f2b387", kill_on_drop: false }`
[INFO] [stdout] 929392c6ef37b42723495dc14f6a596531c784e6a8837633ab3f017733f2b387
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-108/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] 4b8d0e92654a5d17268b09a287ae864b92b780fc23aea9914dc75c420c273c86
[INFO] running `Command { std: "docker" "start" "-a" "4b8d0e92654a5d17268b09a287ae864b92b780fc23aea9914dc75c420c273c86", kill_on_drop: false }`
[INFO] [stderr]     Checking futures v0.1.31
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking slab v0.4.4
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling serde v1.0.127
[INFO] [stderr]    Compiling httparse v1.4.1
[INFO] [stderr]     Checking itoa v0.4.7
[INFO] [stderr]     Checking traitobject v0.1.0
[INFO] [stderr]    Compiling typenum v1.13.0
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking gimli v0.25.0
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling openssl v0.10.35
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling crc32fast v1.2.1
[INFO] [stderr]     Checking ahash v0.3.8
[INFO] [stderr]     Checking rustc-demangle v0.1.20
[INFO] [stderr]    Compiling native-tls v0.2.7
[INFO] [stderr]    Compiling lexical-core v0.7.6
[INFO] [stderr]     Checking safemem v0.3.3
[INFO] [stderr]     Checking try-lock v0.2.3
[INFO] [stderr]     Checking typeable v0.1.2
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]     Checking language-tags v0.2.2
[INFO] [stderr]    Compiling encoding_rs v0.8.28
[INFO] [stderr]     Checking static_assertions v1.1.0
[INFO] [stderr]     Checking openssl-probe v0.1.4
[INFO] [stderr]     Checking arrayvec v0.5.2
[INFO] [stderr]     Checking modifier v0.1.0
[INFO] [stderr]     Checking dtoa v0.4.8
[INFO] [stderr]     Checking mime v0.3.16
[INFO] [stderr]     Checking ppv-lite86 v0.2.10
[INFO] [stderr]     Checking sequence_trie v0.3.6
[INFO] [stderr]     Checking fake-simd v0.1.2
[INFO] [stderr]     Checking lazycell v1.3.0
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking term v0.4.6
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking same-file v0.1.3
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling backtrace v0.3.61
[INFO] [stderr]     Checking form_urlencoded v1.0.1
[INFO] [stderr]    Compiling hashbrown v0.7.2
[INFO] [stderr]    Compiling libloading v0.5.2
[INFO] [stderr]     Checking base64 v0.10.1
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking idna v0.1.5
[INFO] [stderr]     Checking net2 v0.2.37
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]     Checking idna v0.2.3
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]     Checking object v0.26.0
[INFO] [stderr]    Compiling hyper v0.12.36
[INFO] [stderr]     Checking unsafe-any v0.4.2
[INFO] [stderr]     Checking base64 v0.9.3
[INFO] [stderr]     Checking block-padding v0.1.5
[INFO] [stderr]     Checking num-traits v0.1.43
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking uuid v0.7.4
[INFO] [stderr]     Checking term-painter v0.2.4
[INFO] [stderr]     Checking walkdir v1.0.7
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]    Compiling nom v5.1.2
[INFO] [stderr]     Checking tokio-sync v0.1.8
[INFO] [stderr]     Checking want v0.2.0
[INFO] [stderr]     Checking futures-cpupool v0.1.8
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking url v2.2.2
[INFO] [stderr]     Checking typemap v0.3.3
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking mio v0.6.23
[INFO] [stderr]     Checking mime v0.2.6
[INFO] [stderr]     Checking url v1.7.2
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking plugin v0.2.6
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking http v0.1.21
[INFO] [stderr]     Checking string v0.2.1
[INFO] [stderr]     Checking tokio-buf v0.1.1
[INFO] [stderr]     Checking publicsuffix v1.5.6
[INFO] [stderr]     Checking mio-extras v2.0.6
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/hashbrown-0.7.2/src/lib.rs:15:5
[INFO] [stdout]    |
[INFO] [stdout] 15 | /     feature(
[INFO] [stdout] 16 | |         alloc_layout_extra,
[INFO] [stdout] 17 | |         allocator_api,
[INFO] [stdout] 18 | |         ptr_offset_from,
[INFO] [stdout] ...  |
[INFO] [stdout] 22 | |         specialization,
[INFO] [stdout] 23 | |     )
[INFO] [stdout]    | |_____^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking cookie v0.12.0
[INFO] [stderr]     Checking addr2line v0.16.0
[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr]     Checking hyper v0.10.16
[INFO] [stderr] error: could not compile `hashbrown` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "4b8d0e92654a5d17268b09a287ae864b92b780fc23aea9914dc75c420c273c86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b8d0e92654a5d17268b09a287ae864b92b780fc23aea9914dc75c420c273c86", kill_on_drop: false }`
[INFO] [stdout] 4b8d0e92654a5d17268b09a287ae864b92b780fc23aea9914dc75c420c273c86
