[INFO] fetching crate cortex-m-async 0.1.0...
[INFO] testing cortex-m-async-0.1.0 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate cortex-m-async 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate cortex-m-async 0.1.0 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cortex-m-async 0.1.0
[INFO] finished tweaking crates.io crate cortex-m-async 0.1.0
[INFO] tweaked toml for crates.io crate cortex-m-async 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded pin-project-lite v0.2.7
[INFO] [stderr]   Downloaded futures-io v0.3.17
[INFO] [stderr]   Downloaded futures-channel v0.3.17
[INFO] [stderr]   Downloaded pin-utils v0.1.0
[INFO] [stderr]   Downloaded futures-util v0.3.17
[INFO] [stderr]   Downloaded futures-core v0.3.17
[INFO] [stderr]   Downloaded futures-task v0.3.17
[INFO] [stderr]   Downloaded futures v0.3.17
[INFO] [stderr]   Downloaded futures-sink v0.3.17
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c91e37753a18aec995e1750694124bf42d120b1b8d6c7d44283cc26dc53c45a2
[INFO] running `Command { std: "docker" "start" "-a" "c91e37753a18aec995e1750694124bf42d120b1b8d6c7d44283cc26dc53c45a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c91e37753a18aec995e1750694124bf42d120b1b8d6c7d44283cc26dc53c45a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c91e37753a18aec995e1750694124bf42d120b1b8d6c7d44283cc26dc53c45a2", kill_on_drop: false }`
[INFO] [stdout] c91e37753a18aec995e1750694124bf42d120b1b8d6c7d44283cc26dc53c45a2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d7ff0eab9b36efe1ebe8e619caf3a616076734f4ea60410d25df1dba187f454c
[INFO] running `Command { std: "docker" "start" "-a" "d7ff0eab9b36efe1ebe8e619caf3a616076734f4ea60410d25df1dba187f454c", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-core v0.3.17
[INFO] [stderr]    Compiling cortex-m v0.7.3
[INFO] [stderr]    Compiling nb v1.0.0
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling vcell v0.1.3
[INFO] [stderr]    Compiling futures-sink v0.3.17
[INFO] [stderr]    Compiling stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling futures-channel v0.3.17
[INFO] [stderr]    Compiling bitfield v0.13.2
[INFO] [stderr]    Compiling cortex-m v0.6.7
[INFO] [stderr]    Compiling futures-io v0.3.17
[INFO] [stderr]    Compiling futures-util v0.3.17
[INFO] [stderr]    Compiling generic-array v0.12.4
[INFO] [stderr]    Compiling generic-array v0.13.3
[INFO] [stderr]    Compiling bare-metal v0.2.5
[INFO] [stderr]    Compiling volatile-register v0.2.1
[INFO] [stderr]    Compiling nb v0.1.3
[INFO] [stderr]    Compiling embedded-hal v0.2.6
[INFO] [stderr]    Compiling as-slice v0.1.5
[INFO] [stderr]    Compiling aligned v0.3.5
[INFO] [stderr]    Compiling futures v0.3.17
[INFO] [stderr]    Compiling cortex-m-async v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:2:24
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(never_type, const_fn)]
[INFO] [stdout]   |                        ^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: split into finer-grained feature gates
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(never_type, const_fn)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `cortex-m-async` due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "d7ff0eab9b36efe1ebe8e619caf3a616076734f4ea60410d25df1dba187f454c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d7ff0eab9b36efe1ebe8e619caf3a616076734f4ea60410d25df1dba187f454c", kill_on_drop: false }`
[INFO] [stdout] d7ff0eab9b36efe1ebe8e619caf3a616076734f4ea60410d25df1dba187f454c