[INFO] fetching crate intercom 0.3.0...
[INFO] testing intercom-0.3.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate intercom 0.3.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate intercom 0.3.0 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 intercom 0.3.0
[INFO] finished tweaking crates.io crate intercom 0.3.0
[INFO] tweaked toml for crates.io crate intercom 0.3.0 written to /workspace/builds/worker-2/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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] b2eebb5319027a877f8c7c4b41d52f8229658ef7d4c53f04e3c6b8b3cd1d5346
[INFO] running `Command { std: "docker" "start" "-a" "b2eebb5319027a877f8c7c4b41d52f8229658ef7d4c53f04e3c6b8b3cd1d5346", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b2eebb5319027a877f8c7c4b41d52f8229658ef7d4c53f04e3c6b8b3cd1d5346", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b2eebb5319027a877f8c7c4b41d52f8229658ef7d4c53f04e3c6b8b3cd1d5346", kill_on_drop: false }`
[INFO] [stdout] b2eebb5319027a877f8c7c4b41d52f8229658ef7d4c53f04e3c6b8b3cd1d5346
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 4a55fc6b05f6a5f9e8c80c907d13460dd1c904792277801a256facaf28d172ba
[INFO] running `Command { std: "docker" "start" "-a" "4a55fc6b05f6a5f9e8c80c907d13460dd1c904792277801a256facaf28d172ba", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling itoa v0.4.7
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling lazy_static v0.2.11
[INFO] [stderr]    Compiling pest v0.3.3
[INFO] [stderr]    Compiling quick-error v1.2.3
[INFO] [stderr]    Compiling sha1 v0.3.0
[INFO] [stderr]    Compiling ordermap v0.3.5
[INFO] [stderr]    Compiling object v0.26.0
[INFO] [stderr]    Compiling toml v0.4.10
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling handlebars v0.29.1
[INFO] [stderr]    Compiling backtrace v0.3.61
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling intercom-common v0.3.0
[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/intercom-common-0.3.0/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(non_exhaustive)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `non_exhaustive` has been stable since 1.40.0 and no longer requires an attribute to enable
[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 `intercom-common`
[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" "4a55fc6b05f6a5f9e8c80c907d13460dd1c904792277801a256facaf28d172ba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4a55fc6b05f6a5f9e8c80c907d13460dd1c904792277801a256facaf28d172ba", kill_on_drop: false }`
[INFO] [stdout] 4a55fc6b05f6a5f9e8c80c907d13460dd1c904792277801a256facaf28d172ba
