[INFO] fetching crate umbra-lang 0.20.0...
[INFO] documenting umbra-lang-0.20.0 against 1.54.0 for beta-1.55-rustdoc-1
[INFO] extracting crate umbra-lang 0.20.0 into /workspace/builds/worker-88/source
[INFO] validating manifest of crates.io crate umbra-lang 0.20.0 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 umbra-lang 0.20.0
[INFO] finished tweaking crates.io crate umbra-lang 0.20.0
[INFO] tweaked toml for crates.io crate umbra-lang 0.20.0 written to /workspace/builds/worker-88/source/Cargo.toml
[INFO] crate crates.io crate umbra-lang 0.20.0 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-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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] 8a969a3a0d9b8b03e84ae0f8892ee6990c29c27e4ae7fb65815d1ee677717ec9
[INFO] running `Command { std: "docker" "start" "-a" "8a969a3a0d9b8b03e84ae0f8892ee6990c29c27e4ae7fb65815d1ee677717ec9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8a969a3a0d9b8b03e84ae0f8892ee6990c29c27e4ae7fb65815d1ee677717ec9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8a969a3a0d9b8b03e84ae0f8892ee6990c29c27e4ae7fb65815d1ee677717ec9", kill_on_drop: false }`
[INFO] [stdout] 8a969a3a0d9b8b03e84ae0f8892ee6990c29c27e4ae7fb65815d1ee677717ec9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-88/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] 889c8255441def5717c552ddc18a87a706d868d6c976f8062e793cdc1f6d109d
[INFO] running `Command { std: "docker" "start" "-a" "889c8255441def5717c552ddc18a87a706d868d6c976f8062e793cdc1f6d109d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling cc v1.0.67
[INFO] [stderr]    Compiling fs_extra v1.2.0
[INFO] [stderr]     Checking bytecount v0.6.2
[INFO] [stderr]     Checking maplit v1.0.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-bigint v0.4.0
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking itertools v0.10.0
[INFO] [stderr]    Compiling jemalloc-sys v0.3.2
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking env_logger v0.8.3
[INFO] [stderr]     Checking num-integer v0.1.44
[INFO] [stderr]     Checking redox_liner v0.5.1
[INFO] [stderr]     Checking jemallocator v0.3.2
[INFO] [stderr]  Documenting umbra-lang v0.20.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:37:1
[INFO] [stdout]    |
[INFO] [stdout] 37 | #![feature(const_generics)]
[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:39:1
[INFO] [stdout]    |
[INFO] [stdout] 39 | #![feature(iter_intersperse)]
[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] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `umbra-lang`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name umbra_lang src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="env_logger"' --cfg 'feature="jemallocator"' --cfg 'feature="redox_liner"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-04f7947d9f1412cb.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-9c436d67d12d7b9e.rmeta --extern jemallocator=/opt/rustwide/target/debug/deps/libjemallocator-1002bbaff4d869d1.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-acd7d23482fe8b54.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-f8abb66ffc16068c.rmeta --extern maplit=/opt/rustwide/target/debug/deps/libmaplit-edcadb5581f67864.rmeta --extern num_bigint=/opt/rustwide/target/debug/deps/libnum_bigint-797d26f2b5427232.rmeta --extern num_rational=/opt/rustwide/target/debug/deps/libnum_rational-40e6b3c492142c9e.rmeta --extern num_traits=/opt/rustwide/target/debug/deps/libnum_traits-36a9706cfe4ada58.rmeta --extern liner=/opt/rustwide/target/debug/deps/libliner-5a45da088b4c4e2a.rmeta --extern regex=/opt/rustwide/target/debug/deps/libregex-46bf5b535d6b6b09.rmeta --cap-lints=warn --crate-version 0.20.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "889c8255441def5717c552ddc18a87a706d868d6c976f8062e793cdc1f6d109d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "889c8255441def5717c552ddc18a87a706d868d6c976f8062e793cdc1f6d109d", kill_on_drop: false }`
[INFO] [stdout] 889c8255441def5717c552ddc18a87a706d868d6c976f8062e793cdc1f6d109d
