[INFO] fetching crate stepper-driver 0.1.0...
[INFO] testing stepper-driver-0.1.0 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate stepper-driver 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate stepper-driver 0.1.0 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate stepper-driver 0.1.0
[INFO] finished tweaking crates.io crate stepper-driver 0.1.0
[INFO] tweaked toml for crates.io crate stepper-driver 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded void v1.0.2
[INFO] [stderr]   Downloaded embedded-hal v0.2.6
[INFO] [stderr]   Downloaded nb v0.1.3
[INFO] [stderr]   Downloaded embedded-hal v0.1.3
[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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1569ffc90568f89d091839dc976bd3a08c799ebbdb00cedbb2214ffafd867494
[INFO] running `Command { std: "docker" "start" "-a" "1569ffc90568f89d091839dc976bd3a08c799ebbdb00cedbb2214ffafd867494", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1569ffc90568f89d091839dc976bd3a08c799ebbdb00cedbb2214ffafd867494", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1569ffc90568f89d091839dc976bd3a08c799ebbdb00cedbb2214ffafd867494", kill_on_drop: false }`
[INFO] [stdout] 1569ffc90568f89d091839dc976bd3a08c799ebbdb00cedbb2214ffafd867494
[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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 21c54583ca1a0a6781e13ee5b5b88c4455b07650b6290776319490a4576e0dd9
[INFO] running `Command { std: "docker" "start" "-a" "21c54583ca1a0a6781e13ee5b5b88c4455b07650b6290776319490a4576e0dd9", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling nb v1.0.0
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling nb v0.1.3
[INFO] [stderr]    Compiling embedded-hal v0.2.6
[INFO] [stderr]    Compiling embedded-hal v0.1.3
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/embedded-hal-0.1.3/src/lib.rs:681:1
[INFO] [stdout]     |
[INFO] [stdout] 681 | #![feature(never_type)]
[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 `embedded-hal` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "21c54583ca1a0a6781e13ee5b5b88c4455b07650b6290776319490a4576e0dd9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21c54583ca1a0a6781e13ee5b5b88c4455b07650b6290776319490a4576e0dd9", kill_on_drop: false }`
[INFO] [stdout] 21c54583ca1a0a6781e13ee5b5b88c4455b07650b6290776319490a4576e0dd9
