[INFO] fetching crate mfcc 0.1.0...
[INFO] documenting mfcc-0.1.0 against 1.75.0 for beta-1.76-rustdoc-1
[INFO] extracting crate mfcc 0.1.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate mfcc 0.1.0 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", 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-7-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded transpose v0.1.0
[INFO] [stderr]   Downloaded fftw-sys v0.5.0
[INFO] [stderr]   Downloaded fftw v0.6.2
[INFO] [stderr]   Downloaded rustfft v3.0.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 880bdb1cf82559273a5c447449cb6a0dc6ad717261500f245148d3fb76b2dff7
[INFO] running `Command { std: "docker" "start" "-a" "880bdb1cf82559273a5c447449cb6a0dc6ad717261500f245148d3fb76b2dff7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "880bdb1cf82559273a5c447449cb6a0dc6ad717261500f245148d3fb76b2dff7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "880bdb1cf82559273a5c447449cb6a0dc6ad717261500f245148d3fb76b2dff7", kill_on_drop: false }`
[INFO] [stdout] 880bdb1cf82559273a5c447449cb6a0dc6ad717261500f245148d3fb76b2dff7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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" "RUSTFLAGS=--cap-lints=warn" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 278873e7aa360f73535d8a5b405f4e4ad7808340869a486f65729117a47d1c6c
[INFO] running `Command { std: "docker" "start" "-a" "278873e7aa360f73535d8a5b405f4e4ad7808340869a486f65729117a47d1c6c", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]     Checking strength_reduce v0.2.4
[INFO] [stderr]     Checking transpose v0.1.0
[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 stable release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[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 stable release channel
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(test)]
[INFO] [stdout]   |            ^^^^
[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 `mfcc`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `/opt/rustwide/rustup-home/toolchains/1.75.0-x86_64-unknown-linux-gnu/bin/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,artifacts,future-incompat --document-private-items -C metadata=db67040ba1b14693 -L dependency=/opt/rustwide/target/debug/deps --extern num_complex=/opt/rustwide/target/debug/deps/libnum_complex-1aac14b14955496c.rmeta --extern rustfft=/opt/rustwide/target/debug/deps/librustfft-79203c42e27377d7.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "278873e7aa360f73535d8a5b405f4e4ad7808340869a486f65729117a47d1c6c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "278873e7aa360f73535d8a5b405f4e4ad7808340869a486f65729117a47d1c6c", kill_on_drop: false }`
[INFO] [stdout] 278873e7aa360f73535d8a5b405f4e4ad7808340869a486f65729117a47d1c6c
