[INFO] fetching crate mfcc 0.1.0...
[INFO] testing mfcc-0.1.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate mfcc 0.1.0 into /workspace/builds/worker-115/source
[INFO] validating manifest of crates.io crate mfcc 0.1.0 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 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-115/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/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] f07e1bdf3e0eeea8d1e86eb160fae59e3e6159406934dd1f5143eb792cb28c2d
[INFO] running `Command { std: "docker" "start" "-a" "f07e1bdf3e0eeea8d1e86eb160fae59e3e6159406934dd1f5143eb792cb28c2d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f07e1bdf3e0eeea8d1e86eb160fae59e3e6159406934dd1f5143eb792cb28c2d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f07e1bdf3e0eeea8d1e86eb160fae59e3e6159406934dd1f5143eb792cb28c2d", kill_on_drop: false }`
[INFO] [stdout] f07e1bdf3e0eeea8d1e86eb160fae59e3e6159406934dd1f5143eb792cb28c2d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-115/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" "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" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f6bd8f6429f80d8bce2ad1ac9e97165a27db5e4ceabb50bf9bd1f75783d3679a
[INFO] running `Command { std: "docker" "start" "-a" "f6bd8f6429f80d8bce2ad1ac9e97165a27db5e4ceabb50bf9bd1f75783d3679a", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling transpose v0.1.0
[INFO] [stderr]    Compiling strength_reduce v0.2.3
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling rustfft v3.0.1
[INFO] [stderr]    Compiling 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:1:1
[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 stable 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: 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 compile `mfcc`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "f6bd8f6429f80d8bce2ad1ac9e97165a27db5e4ceabb50bf9bd1f75783d3679a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f6bd8f6429f80d8bce2ad1ac9e97165a27db5e4ceabb50bf9bd1f75783d3679a", kill_on_drop: false }`
[INFO] [stdout] f6bd8f6429f80d8bce2ad1ac9e97165a27db5e4ceabb50bf9bd1f75783d3679a
