[INFO] fetching crate embedded-executor 0.6.1...
[INFO] checking embedded-executor-0.6.1 against beta for pr-78714
[INFO] extracting crate embedded-executor 0.6.1 into /workspace/builds/worker-10/source
[INFO] validating manifest of crates.io crate embedded-executor 0.6.1 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate embedded-executor 0.6.1
[INFO] finished tweaking crates.io crate embedded-executor 0.6.1
[INFO] tweaked toml for crates.io crate embedded-executor 0.6.1 written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bb5d5bacb67422dc22de9a5f5e97c1317eaebb1fb875b9c691de5ca0a815fbe1
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "bb5d5bacb67422dc22de9a5f5e97c1317eaebb1fb875b9c691de5ca0a815fbe1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bb5d5bacb67422dc22de9a5f5e97c1317eaebb1fb875b9c691de5ca0a815fbe1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bb5d5bacb67422dc22de9a5f5e97c1317eaebb1fb875b9c691de5ca0a815fbe1", kill_on_drop: false }`
[INFO] [stdout] bb5d5bacb67422dc22de9a5f5e97c1317eaebb1fb875b9c691de5ca0a815fbe1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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=forbid" "-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" "rustops/crates-build-env@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 634a0e0d90cbf7aa9aa1b82be9a7b8e91e6436c933fc1944b613975a07c76885
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "634a0e0d90cbf7aa9aa1b82be9a7b8e91e6436c933fc1944b613975a07c76885", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.48
[INFO] [stderr]     Checking futures-sink v0.3.8
[INFO] [stderr]     Checking futures-io v0.3.8
[INFO] [stderr]     Checking alloc-facade v0.5.0
[INFO] [stderr]     Checking generational-arena v0.2.8
[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/generational-arena-0.2.8/src/lib.rs:146:35
[INFO] [stdout]     |
[INFO] [stdout] 146 | #![cfg_attr(not(feature = "std"), feature(alloc))]
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking futures-channel v0.3.8
[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 `generational-arena`
[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" "634a0e0d90cbf7aa9aa1b82be9a7b8e91e6436c933fc1944b613975a07c76885", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "634a0e0d90cbf7aa9aa1b82be9a7b8e91e6436c933fc1944b613975a07c76885", kill_on_drop: false }`
[INFO] [stdout] 634a0e0d90cbf7aa9aa1b82be9a7b8e91e6436c933fc1944b613975a07c76885