[INFO] fetching crate fffft 0.4.0...
[INFO] testing fffft-0.4.0 against 1.60.0 for beta-1.61-1
[INFO] extracting crate fffft 0.4.0 into /workspace/builds/worker-27/source
[INFO] validating manifest of crates.io crate fffft 0.4.0 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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-27/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded addchain v0.2.0
[INFO] [stderr]   Downloaded err-derive v0.2.4
[INFO] [stderr]   Downloaded rug v1.15.0
[INFO] [stderr]   Downloaded ff_derive v0.10.0
[INFO] [stderr]   Downloaded rug-fft v0.1.2
[INFO] [stderr]   Downloaded gmp-mpfr-sys v1.4.8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6940c84a43c03fbe784e12e4b5a70cabd1e5baf32822cae1791d71f5e33c5c03
[INFO] running `Command { std: "docker" "start" "-a" "6940c84a43c03fbe784e12e4b5a70cabd1e5baf32822cae1791d71f5e33c5c03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6940c84a43c03fbe784e12e4b5a70cabd1e5baf32822cae1791d71f5e33c5c03", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6940c84a43c03fbe784e12e4b5a70cabd1e5baf32822cae1791d71f5e33c5c03", kill_on_drop: false }`
[INFO] [stdout] 6940c84a43c03fbe784e12e4b5a70cabd1e5baf32822cae1791d71f5e33c5c03
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-27/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c9ca0d38b339c0e45e7366bf7a94c77b9cd358e11d5afffc52f352c90e0ec7a0
[INFO] running `Command { std: "docker" "start" "-a" "c9ca0d38b339c0e45e7366bf7a94c77b9cd358e11d5afffc52f352c90e0ec7a0", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling rustversion v1.0.6
[INFO] [stderr]    Compiling radium v0.6.2
[INFO] [stderr]    Compiling funty v1.2.0
[INFO] [stderr]    Compiling subtle v2.4.1
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.3.3
[INFO] [stderr]    Compiling wyz v0.4.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling bitvec v0.22.3
[INFO] [stderr]    Compiling err-derive v0.2.4
[INFO] [stderr]    Compiling addchain v0.2.0
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling synstructure v0.12.6
[INFO] [stderr]    Compiling ff_derive v0.10.0
[INFO] [stderr]    Compiling ff v0.10.1
[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:16:12
[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` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "c9ca0d38b339c0e45e7366bf7a94c77b9cd358e11d5afffc52f352c90e0ec7a0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9ca0d38b339c0e45e7366bf7a94c77b9cd358e11d5afffc52f352c90e0ec7a0", kill_on_drop: false }`
[INFO] [stdout] c9ca0d38b339c0e45e7366bf7a94c77b9cd358e11d5afffc52f352c90e0ec7a0