[INFO] crate uwl 0.6.0 is already in cache
[INFO] testing uwl-0.6.0 against 1.45.2 for beta-1.46-1
[INFO] extracting crate uwl 0.6.0 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate uwl 0.6.0 on toolchain 1.45.2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate uwl 0.6.0
[INFO] finished tweaking crates.io crate uwl 0.6.0
[INFO] tweaked toml for crates.io crate uwl 0.6.0 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.45.2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 98daf03dda4328cceeff64ed0068ffd0732613735cfbb480e3d73a54c749575f
[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" "98daf03dda4328cceeff64ed0068ffd0732613735cfbb480e3d73a54c749575f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "98daf03dda4328cceeff64ed0068ffd0732613735cfbb480e3d73a54c749575f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98daf03dda4328cceeff64ed0068ffd0732613735cfbb480e3d73a54c749575f", kill_on_drop: false }`
[INFO] [stdout] 98daf03dda4328cceeff64ed0068ffd0732613735cfbb480e3d73a54c749575f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 584abb33bb84ab8c2137c1e8e56ba14ccf2efedf440f543a29293ed5e3e4b50f
[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" "584abb33bb84ab8c2137c1e8e56ba14ccf2efedf440f543a29293ed5e3e4b50f", kill_on_drop: false }`
[INFO] [stderr]    Compiling uwl v0.6.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.23s
[INFO] running `Command { std: "docker" "inspect" "584abb33bb84ab8c2137c1e8e56ba14ccf2efedf440f543a29293ed5e3e4b50f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "584abb33bb84ab8c2137c1e8e56ba14ccf2efedf440f543a29293ed5e3e4b50f", kill_on_drop: false }`
[INFO] [stdout] 584abb33bb84ab8c2137c1e8e56ba14ccf2efedf440f543a29293ed5e3e4b50f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+1.45.2" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6f3fed6f5430e1936c3cb0c153cf427049b9a65673b4e26a163b0f3a281bba93
[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" "6f3fed6f5430e1936c3cb0c153cf427049b9a65673b4e26a163b0f3a281bba93", kill_on_drop: false }`
[INFO] [stderr]    Compiling uwl v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:90:19
[INFO] [stdout]    |
[INFO] [stdout] 90 | #![cfg_attr(test, feature(test))]
[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 `uwl`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "6f3fed6f5430e1936c3cb0c153cf427049b9a65673b4e26a163b0f3a281bba93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f3fed6f5430e1936c3cb0c153cf427049b9a65673b4e26a163b0f3a281bba93", kill_on_drop: false }`
[INFO] [stdout] 6f3fed6f5430e1936c3cb0c153cf427049b9a65673b4e26a163b0f3a281bba93