[INFO] fetching crate thinbox 0.1.3...
[INFO] testing thinbox-0.1.3 against 1.49.0 for beta-1.50-1
[INFO] extracting crate thinbox 0.1.3 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate thinbox 0.1.3 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 thinbox 0.1.3
[INFO] finished tweaking crates.io crate thinbox 0.1.3
[INFO] tweaked toml for crates.io crate thinbox 0.1.3 written to /workspace/builds/worker-0/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-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d04668c910b294eff47d9b8ce0130a9fca8b841610cb42f0c0901dddf44102a4
[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" "d04668c910b294eff47d9b8ce0130a9fca8b841610cb42f0c0901dddf44102a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d04668c910b294eff47d9b8ce0130a9fca8b841610cb42f0c0901dddf44102a4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d04668c910b294eff47d9b8ce0130a9fca8b841610cb42f0c0901dddf44102a4", kill_on_drop: false }`
[INFO] [stdout] d04668c910b294eff47d9b8ce0130a9fca8b841610cb42f0c0901dddf44102a4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 191fbd831c3eb513cc395116ddfffcef41ed034351435e3b137b1cb331590b1a
[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" "191fbd831c3eb513cc395116ddfffcef41ed034351435e3b137b1cb331590b1a", kill_on_drop: false }`
[INFO] [stderr]    Compiling thinbox v0.1.3 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:12:1
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![feature(raw)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:13:1
[INFO] [stdout]    |
[INFO] [stdout] 13 | #![feature(unsize)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `thinbox`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "191fbd831c3eb513cc395116ddfffcef41ed034351435e3b137b1cb331590b1a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "191fbd831c3eb513cc395116ddfffcef41ed034351435e3b137b1cb331590b1a", kill_on_drop: false }`
[INFO] [stdout] 191fbd831c3eb513cc395116ddfffcef41ed034351435e3b137b1cb331590b1a