[INFO] fetching crate ruffbox_synth 0.9.0...
[INFO] testing ruffbox_synth-0.9.0 against 1.75.0 for beta-1.76-1
[INFO] extracting crate ruffbox_synth 0.9.0 into /workspace/builds/worker-6-tc1/source
[INFO] validating manifest of crates.io crate ruffbox_synth 0.9.0 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 ruffbox_synth 0.9.0
[INFO] finished tweaking crates.io crate ruffbox_synth 0.9.0
[INFO] tweaked toml for crates.io crate ruffbox_synth 0.9.0 written to /workspace/builds/worker-6-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 chfft v0.3.4
[INFO] [stderr]   Downloaded realfft v2.0.1
[INFO] [stderr]   Downloaded rubato v0.10.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 77eac322d734c8421f431b78f19ed6d40f25b332b2dc78e7ebe779dd6be9c5f3
[INFO] running `Command { std: "docker" "start" "-a" "77eac322d734c8421f431b78f19ed6d40f25b332b2dc78e7ebe779dd6be9c5f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "77eac322d734c8421f431b78f19ed6d40f25b332b2dc78e7ebe779dd6be9c5f3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "77eac322d734c8421f431b78f19ed6d40f25b332b2dc78e7ebe779dd6be9c5f3", kill_on_drop: false }`
[INFO] [stdout] 77eac322d734c8421f431b78f19ed6d40f25b332b2dc78e7ebe779dd6be9c5f3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 82816dea2eb52a39a16d9b231d6fccf51eb5eee8284ece742cd1424dac671ae9
[INFO] running `Command { std: "docker" "start" "-a" "82816dea2eb52a39a16d9b231d6fccf51eb5eee8284ece742cd1424dac671ae9", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.17
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stderr]    Compiling crossbeam-utils v0.8.18
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]    Compiling lock_api v0.4.11
[INFO] [stderr]    Compiling smallvec v1.11.2
[INFO] [stderr]    Compiling strength_reduce v0.2.4
[INFO] [stderr]    Compiling scopeguard v1.2.0
[INFO] [stderr]    Compiling parking_lot_core v0.8.6
[INFO] [stderr]    Compiling parking_lot_core v0.9.9
[INFO] [stderr]    Compiling hashbrown v0.14.3
[INFO] [stderr]    Compiling fastrand v1.9.0
[INFO] [stderr]    Compiling rustfft v6.1.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.17
[INFO] [stderr]    Compiling crossbeam-queue v0.3.10
[INFO] [stderr]    Compiling crossbeam-channel v0.5.10
[INFO] [stderr]    Compiling crossbeam-deque v0.8.4
[INFO] [stderr]    Compiling crossbeam v0.8.3
[INFO] [stderr]    Compiling parking_lot v0.11.2
[INFO] [stderr]    Compiling dashmap v5.5.3
[INFO] [stderr]    Compiling num-complex v0.4.4
[INFO] [stderr]    Compiling transpose v0.2.2
[INFO] [stderr]    Compiling primal-check v0.3.3
[INFO] [stderr]    Compiling chfft v0.3.4
[INFO] [stderr]    Compiling realfft v2.0.1
[INFO] [stderr]    Compiling rubato v0.10.1
[INFO] [stderr]    Compiling ruffbox_synth v0.9.0 (/opt/rustwide/workdir)
[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(get_many_mut)]
[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 `ruffbox_synth` (lib) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "82816dea2eb52a39a16d9b231d6fccf51eb5eee8284ece742cd1424dac671ae9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82816dea2eb52a39a16d9b231d6fccf51eb5eee8284ece742cd1424dac671ae9", kill_on_drop: false }`
[INFO] [stdout] 82816dea2eb52a39a16d9b231d6fccf51eb5eee8284ece742cd1424dac671ae9
