[INFO] fetching crate taikai 0.1.0...
[INFO] documenting taikai-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate taikai 0.1.0 into /workspace/builds/worker-36/source
[INFO] validating manifest of crates.io crate taikai 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 taikai 0.1.0
[INFO] finished tweaking crates.io crate taikai 0.1.0
[INFO] tweaked toml for crates.io crate taikai 0.1.0 written to /workspace/builds/worker-36/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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tuple_utils v0.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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] a65e08f78458f360dd1ae09fcc352cc9a4246ebd5f1ed30d68854cda09a08692
[INFO] running `Command { std: "docker" "start" "-a" "a65e08f78458f360dd1ae09fcc352cc9a4246ebd5f1ed30d68854cda09a08692", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a65e08f78458f360dd1ae09fcc352cc9a4246ebd5f1ed30d68854cda09a08692", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a65e08f78458f360dd1ae09fcc352cc9a4246ebd5f1ed30d68854cda09a08692", kill_on_drop: false }`
[INFO] [stdout] a65e08f78458f360dd1ae09fcc352cc9a4246ebd5f1ed30d68854cda09a08692
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-36/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] a1900640f73ae054f8611f2819ed426561b8fbd2d2c814e875e638ef6c6dfdf4
[INFO] running `Command { std: "docker" "start" "-a" "a1900640f73ae054f8611f2819ed426561b8fbd2d2c814e875e638ef6c6dfdf4", kill_on_drop: false }`
[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 memchr v2.5.0
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.2.3
[INFO] [stderr]     Checking gimli v0.26.1
[INFO] [stderr]     Checking unicode-xid v0.1.0
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling serde v1.0.137
[INFO] [stderr]     Checking hashbrown v0.11.2
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]    Compiling serde_derive v1.0.137
[INFO] [stderr]     Checking rustc-demangle v0.1.21
[INFO] [stderr]    Compiling encoding_rs v0.8.31
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking unicode-segmentation v1.9.0
[INFO] [stderr]     Checking ryu v1.0.10
[INFO] [stderr]     Checking miniz_oxide v0.5.3
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr]    Compiling indexmap v1.8.2
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]     Checking object v0.28.4
[INFO] [stderr]    Compiling backtrace v0.3.65
[INFO] [stderr]     Checking quote v0.6.13
[INFO] [stderr]     Checking addr2line v0.17.0
[INFO] [stderr]     Checking serde_yaml v0.8.24
[INFO] [stderr]    Compiling synstructure v0.12.6
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]  Documenting taikai v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:4:12
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(custom_attribute)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: removed in favor of `#![register_tool]` and `#![register_attr]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(bind_by_move_pattern_guards)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `bind_by_move_pattern_guards` has been stable since 1.39.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(custom_attribute)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(proc_macro_span)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(try_blocks)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 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 `taikai`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type proc-macro --crate-name taikai src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=bb8f9666e022a4e8 -L dependency=/opt/rustwide/target/debug/deps --extern encoding_rs=/opt/rustwide/target/debug/deps/libencoding_rs-56b567f9b7e51f05.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-79378ea27c8ca071.rmeta --extern heck=/opt/rustwide/target/debug/deps/libheck-ea3b5184be63e654.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-237e07c83799a2ab.rmeta --extern proc_macro2=/opt/rustwide/target/debug/deps/libproc_macro2-42b8f402e5615b33.rmeta --extern quote=/opt/rustwide/target/debug/deps/libquote-45a3d718982da057.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-495ec9fdc6b7531e.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-cbe02c8b7676a721.so --extern serde_yaml=/opt/rustwide/target/debug/deps/libserde_yaml-c16e12a8e2d28fa8.rmeta --extern syn=/opt/rustwide/target/debug/deps/libsyn-370674f8412a7c95.rmeta --extern proc_macro --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "a1900640f73ae054f8611f2819ed426561b8fbd2d2c814e875e638ef6c6dfdf4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a1900640f73ae054f8611f2819ed426561b8fbd2d2c814e875e638ef6c6dfdf4", kill_on_drop: false }`
[INFO] [stdout] a1900640f73ae054f8611f2819ed426561b8fbd2d2c814e875e638ef6c6dfdf4