[INFO] fetching crate scpi 0.3.5...
[INFO] testing scpi-0.3.5 against 1.49.0 for beta-1.50-1
[INFO] extracting crate scpi 0.3.5 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate scpi 0.3.5 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate scpi 0.3.5
[INFO] finished tweaking crates.io crate scpi 0.3.5
[INFO] tweaked toml for crates.io crate scpi 0.3.5 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 28dec88b1b57a933f954ff5ace439e315c04aeda2a233cba6996459a5828ef75
[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" "28dec88b1b57a933f954ff5ace439e315c04aeda2a233cba6996459a5828ef75", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "28dec88b1b57a933f954ff5ace439e315c04aeda2a233cba6996459a5828ef75", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "28dec88b1b57a933f954ff5ace439e315c04aeda2a233cba6996459a5828ef75", kill_on_drop: false }`
[INFO] [stdout] 28dec88b1b57a933f954ff5ace439e315c04aeda2a233cba6996459a5828ef75
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 201fee45ead5946dd8b472e7f3bf28afb299913a23ab89e0a88504771d6e55b6
[INFO] running `Command { std: "docker" "start" "-a" "201fee45ead5946dd8b472e7f3bf28afb299913a23ab89e0a88504771d6e55b6", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling serde v1.0.118
[INFO] [stderr]    Compiling arraydeque v0.4.5
[INFO] [stderr]    Compiling lexical-core v0.7.4
[INFO] [stderr]    Compiling arrayvec v0.5.2
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-rational v0.3.2
[INFO] [stderr]    Compiling semver v0.10.0
[INFO] [stderr]    Compiling jobserver v0.1.21
[INFO] [stderr]    Compiling scpi_derive v0.3.5
[INFO] [stderr]    Compiling cc v1.0.66
[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/lexical-core-0.7.4/src/lib.rs:133:35
[INFO] [stdout]     |
[INFO] [stdout] 133 | #![cfg_attr(not(feature = "std"), feature(core_intrinsics))]
[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 `lexical-core`
[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" "201fee45ead5946dd8b472e7f3bf28afb299913a23ab89e0a88504771d6e55b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "201fee45ead5946dd8b472e7f3bf28afb299913a23ab89e0a88504771d6e55b6", kill_on_drop: false }`
[INFO] [stdout] 201fee45ead5946dd8b472e7f3bf28afb299913a23ab89e0a88504771d6e55b6