[INFO] fetching crate mhrono 0.1.0...
[INFO] documenting mhrono-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate mhrono 0.1.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate mhrono 0.1.0 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mhrono 0.1.0
[INFO] finished tweaking crates.io crate mhrono 0.1.0
[INFO] tweaked toml for crates.io crate mhrono 0.1.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded chrono-tz-build v0.0.2
[INFO] [stderr]   Downloaded uncased v0.9.7
[INFO] [stderr]   Downloaded phf_codegen v0.10.0
[INFO] [stderr]   Downloaded parse-zoneinfo v0.3.0
[INFO] [stderr]   Downloaded eyre v0.6.8
[INFO] [stderr]   Downloaded chrono-tz v0.6.1
[INFO] [stderr]   Downloaded moldenfile v0.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 906a875ba06f5d0f6c15c0fcccc21d391ea5eefcc165409ab1e835c56e64c257
[INFO] running `Command { std: "docker" "start" "-a" "906a875ba06f5d0f6c15c0fcccc21d391ea5eefcc165409ab1e835c56e64c257", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "906a875ba06f5d0f6c15c0fcccc21d391ea5eefcc165409ab1e835c56e64c257", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "906a875ba06f5d0f6c15c0fcccc21d391ea5eefcc165409ab1e835c56e64c257", kill_on_drop: false }`
[INFO] [stdout] 906a875ba06f5d0f6c15c0fcccc21d391ea5eefcc165409ab1e835c56e64c257
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f391736627931330f87a8039476fc1d23f2d599f6f28c5aeefee6d59a4da791e
[INFO] running `Command { std: "docker" "start" "-a" "f391736627931330f87a8039476fc1d23f2d599f6f28c5aeefee6d59a4da791e", kill_on_drop: false }`
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling ppv-lite86 v0.2.16
[INFO] [stderr]    Compiling siphasher v0.3.10
[INFO] [stderr]    Compiling regex-syntax v0.6.26
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling crc32fast v1.3.2
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling eyre v0.6.8
[INFO] [stderr]     Checking indenter v0.3.3
[INFO] [stderr]     Checking remove_dir_all v0.5.3
[INFO] [stderr]     Checking fastrand v1.7.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking once_cell v1.12.0
[INFO] [stderr]    Compiling convert_case v0.4.0
[INFO] [stderr]     Checking dissimilar v1.0.4
[INFO] [stderr]     Checking miniz_oxide v0.5.1
[INFO] [stderr]     Checking flate2 v1.0.24
[INFO] [stderr]    Compiling uncased v0.9.7
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling regex v1.5.6
[INFO] [stderr]    Compiling getrandom v0.2.6
[INFO] [stderr]     Checking time v0.1.44
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking tempfile v3.3.0
[INFO] [stderr]     Checking colored v2.0.0
[INFO] [stderr]    Compiling rand_core v0.6.3
[INFO] [stderr]    Compiling phf_shared v0.10.0
[INFO] [stderr]     Checking moldenfile v0.1.0
[INFO] [stderr]    Compiling rand_chacha v0.3.1
[INFO] [stderr]     Checking phf v0.10.1
[INFO] [stderr]    Compiling parse-zoneinfo v0.3.0
[INFO] [stderr]    Compiling rand v0.8.5
[INFO] [stderr]    Compiling phf_generator v0.10.0
[INFO] [stderr]    Compiling phf_codegen v0.10.0
[INFO] [stderr]    Compiling chrono-tz-build v0.0.2
[INFO] [stderr]    Compiling chrono-tz v0.6.1
[INFO] [stderr]    Compiling num-derive v0.3.3
[INFO] [stderr]    Compiling derive_more v0.99.17
[INFO] [stderr]     Checking chrono v0.4.19
[INFO] [stderr]  Documenting mhrono v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:39:1
[INFO] [stdout]    |
[INFO] [stdout] 39 | #![feature(bool_to_option, once_cell, trait_alias)]
[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 `mhrono`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2021 --crate-type lib --crate-name mhrono src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=b4811490358321c3 -L dependency=/opt/rustwide/target/debug/deps --extern chrono=/opt/rustwide/target/debug/deps/libchrono-a56f17992a9ea472.rmeta --extern chrono_tz=/opt/rustwide/target/debug/deps/libchrono_tz-6009c29cedb40e31.rmeta --extern derive_more=/opt/rustwide/target/debug/deps/libderive_more-530d8285ccdc9732.so --extern eyre=/opt/rustwide/target/debug/deps/libeyre-202a897f576dfc69.rmeta --extern moldenfile=/opt/rustwide/target/debug/deps/libmoldenfile-95c2c2e73d18248e.rmeta --extern num_derive=/opt/rustwide/target/debug/deps/libnum_derive-703506e2d64dc702.so --extern num_traits=/opt/rustwide/target/debug/deps/libnum_traits-c152df0f0b492223.rmeta --extern regex=/opt/rustwide/target/debug/deps/libregex-f5c38302584e07cc.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-5cee9986692918ec.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "f391736627931330f87a8039476fc1d23f2d599f6f28c5aeefee6d59a4da791e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f391736627931330f87a8039476fc1d23f2d599f6f28c5aeefee6d59a4da791e", kill_on_drop: false }`
[INFO] [stdout] f391736627931330f87a8039476fc1d23f2d599f6f28c5aeefee6d59a4da791e