[INFO] fetching crate mfcc 0.1.0...
[INFO] documenting mfcc-0.1.0 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate mfcc 0.1.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate mfcc 0.1.0 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mfcc 0.1.0
[INFO] finished tweaking crates.io crate mfcc 0.1.0
[INFO] tweaked toml for crates.io crate mfcc 0.1.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] eb184aa90b99e83a5fc8031c538d36d2532f63d947e06260016196e125b83521
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "eb184aa90b99e83a5fc8031c538d36d2532f63d947e06260016196e125b83521", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "eb184aa90b99e83a5fc8031c538d36d2532f63d947e06260016196e125b83521", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb184aa90b99e83a5fc8031c538d36d2532f63d947e06260016196e125b83521", kill_on_drop: false }`
[INFO] [stdout] eb184aa90b99e83a5fc8031c538d36d2532f63d947e06260016196e125b83521
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a44d64fe94941ad88a8c51b3d07af2a5da629a0c017326fe6b7f69d5a6730287
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "a44d64fe94941ad88a8c51b3d07af2a5da629a0c017326fe6b7f69d5a6730287", kill_on_drop: false }`
[INFO] [stderr]     Checking transpose v0.1.0
[INFO] [stderr]     Checking strength_reduce v0.2.3
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]     Checking rustfft v3.0.1
[INFO] [stderr]  Documenting mfcc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(core_intrinsics)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(test)]
[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 `mfcc`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name mfcc src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --cfg 'feature="fftrust"' --cfg 'feature="rustfft"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern num_complex=/opt/rustwide/target/debug/deps/libnum_complex-abaea1aaa0244311.rmeta --extern rustfft=/opt/rustwide/target/debug/deps/librustfft-72491e563ed3bd24.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "a44d64fe94941ad88a8c51b3d07af2a5da629a0c017326fe6b7f69d5a6730287", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a44d64fe94941ad88a8c51b3d07af2a5da629a0c017326fe6b7f69d5a6730287", kill_on_drop: false }`
[INFO] [stdout] a44d64fe94941ad88a8c51b3d07af2a5da629a0c017326fe6b7f69d5a6730287