[INFO] fetching crate fffft 0.4.0...
[INFO] testing fffft-0.4.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate fffft 0.4.0 into /workspace/builds/worker-98/source
[INFO] validating manifest of crates.io crate fffft 0.4.0 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 fffft 0.4.0
[INFO] finished tweaking crates.io crate fffft 0.4.0
[INFO] tweaked toml for crates.io crate fffft 0.4.0 written to /workspace/builds/worker-98/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-98/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-98/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] 7b9d9a7852d66bd3e852fab7b9766e5e42d7eb7e3ee0f83a51b59cdd1bedc6a1
[INFO] running `Command { std: "docker" "start" "-a" "7b9d9a7852d66bd3e852fab7b9766e5e42d7eb7e3ee0f83a51b59cdd1bedc6a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7b9d9a7852d66bd3e852fab7b9766e5e42d7eb7e3ee0f83a51b59cdd1bedc6a1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7b9d9a7852d66bd3e852fab7b9766e5e42d7eb7e3ee0f83a51b59cdd1bedc6a1", kill_on_drop: false }`
[INFO] [stdout] 7b9d9a7852d66bd3e852fab7b9766e5e42d7eb7e3ee0f83a51b59cdd1bedc6a1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-98/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-98/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] 90f92aa2b8492a0002ce5a0140402b34ff2f32be760103ef216441eaeda0c40a
[INFO] running `Command { std: "docker" "start" "-a" "90f92aa2b8492a0002ce5a0140402b34ff2f32be760103ef216441eaeda0c40a", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling syn v1.0.74
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling rustversion v1.0.5
[INFO] [stderr]    Compiling radium v0.6.2
[INFO] [stderr]    Compiling tap v1.0.1
[INFO] [stderr]    Compiling funty v1.2.0
[INFO] [stderr]    Compiling subtle v2.4.1
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.3.2
[INFO] [stderr]    Compiling itertools v0.10.1
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling wyz v0.4.0
[INFO] [stderr]    Compiling rand_core v0.6.3
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling bitvec v0.22.3
[INFO] [stderr]    Compiling err-derive v0.2.4
[INFO] [stderr]    Compiling synstructure v0.12.5
[INFO] [stderr]    Compiling addchain v0.2.0
[INFO] [stderr]    Compiling ff_derive v0.10.0
[INFO] [stderr]    Compiling ff v0.10.0
[INFO] [stderr]    Compiling fffft v0.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:16:1
[INFO] [stdout]    |
[INFO] [stdout] 16 | #![feature(test)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `fffft`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "90f92aa2b8492a0002ce5a0140402b34ff2f32be760103ef216441eaeda0c40a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "90f92aa2b8492a0002ce5a0140402b34ff2f32be760103ef216441eaeda0c40a", kill_on_drop: false }`
[INFO] [stdout] 90f92aa2b8492a0002ce5a0140402b34ff2f32be760103ef216441eaeda0c40a
