[INFO] fetching crate unmp-link-serial 0.7.0...
[INFO] testing unmp-link-serial-0.7.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate unmp-link-serial 0.7.0 into /workspace/builds/worker-52/source
[INFO] validating manifest of crates.io crate unmp-link-serial 0.7.0 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 unmp-link-serial 0.7.0
[INFO] finished tweaking crates.io crate unmp-link-serial 0.7.0
[INFO] tweaked toml for crates.io crate unmp-link-serial 0.7.0 written to /workspace/builds/worker-52/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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/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] 4dfcbe1bd053d78bccc6e9cb6ca549878291ec739b4a2cea8fe12ebe802a99ab
[INFO] running `Command { std: "docker" "start" "-a" "4dfcbe1bd053d78bccc6e9cb6ca549878291ec739b4a2cea8fe12ebe802a99ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4dfcbe1bd053d78bccc6e9cb6ca549878291ec739b4a2cea8fe12ebe802a99ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4dfcbe1bd053d78bccc6e9cb6ca549878291ec739b4a2cea8fe12ebe802a99ab", kill_on_drop: false }`
[INFO] [stdout] 4dfcbe1bd053d78bccc6e9cb6ca549878291ec739b4a2cea8fe12ebe802a99ab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-52/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] 6f4bd050884a05b62ff14ebae9c6a55386ca4f52f0824efd48360ceda6ffec32
[INFO] running `Command { std: "docker" "start" "-a" "6f4bd050884a05b62ff14ebae9c6a55386ca4f52f0824efd48360ceda6ffec32", kill_on_drop: false }`
[INFO] [stderr]    Compiling futures-core v0.3.16
[INFO] [stderr]    Compiling futures-task v0.3.16
[INFO] [stderr]    Compiling crc16 v0.4.0
[INFO] [stderr]    Compiling heapless v0.7.4
[INFO] [stderr]    Compiling stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling fixed-queue v0.3.10
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling pin-project-lite v0.2.7
[INFO] [stderr]    Compiling pin-utils v0.1.0
[INFO] [stderr]    Compiling async-task v4.0.3
[INFO] [stderr]    Compiling unmp-id v2.0.0
[INFO] [stderr]    Compiling lock_api v0.4.4
[INFO] [stderr]    Compiling hash32 v0.2.1
[INFO] [stderr]    Compiling futures-util v0.3.16
[INFO] [stderr]    Compiling ioctl-rs v0.1.6
[INFO] [stderr]    Compiling termios v0.2.2
[INFO] [stderr]    Compiling serial-core v0.4.0
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling spin v0.9.2
[INFO] [stderr]    Compiling serial-unix v0.4.0
[INFO] [stderr]    Compiling futures-intrusive v0.4.0
[INFO] [stderr]    Compiling serial v0.4.0
[INFO] [stderr]    Compiling eds v0.4.4
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/eds-0.4.4/src/lib.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(const_panic)]
[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 `eds`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "6f4bd050884a05b62ff14ebae9c6a55386ca4f52f0824efd48360ceda6ffec32", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f4bd050884a05b62ff14ebae9c6a55386ca4f52f0824efd48360ceda6ffec32", kill_on_drop: false }`
[INFO] [stdout] 6f4bd050884a05b62ff14ebae9c6a55386ca4f52f0824efd48360ceda6ffec32
