[INFO] fetching crate cobalt_os 0.1.1...
[INFO] testing cobalt_os-0.1.1 against 1.59.0 for beta-1.60-1
[INFO] extracting crate cobalt_os 0.1.1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate cobalt_os 0.1.1 on toolchain 1.59.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-9/source/.cargo/config.toml
[INFO] removed /workspace/builds/worker-9/source/rust-toolchain
[INFO] started tweaking crates.io crate cobalt_os 0.1.1
[INFO] finished tweaking crates.io crate cobalt_os 0.1.1
[INFO] tweaked toml for crates.io crate cobalt_os 0.1.1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate crates.io crate cobalt_os 0.1.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.59.0" "fetch" "--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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f1d23c7793b652e769110e4228892f0cdea86872b1759149f267dff35504202b
[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" "f1d23c7793b652e769110e4228892f0cdea86872b1759149f267dff35504202b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f1d23c7793b652e769110e4228892f0cdea86872b1759149f267dff35504202b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f1d23c7793b652e769110e4228892f0cdea86872b1759149f267dff35504202b", kill_on_drop: false }`
[INFO] [stdout] f1d23c7793b652e769110e4228892f0cdea86872b1759149f267dff35504202b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+1.59.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 708487c6e6d208444b4486e5a1b845dbbe46e801278d1a9ae20663f0711ed6e4
[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" "708487c6e6d208444b4486e5a1b845dbbe46e801278d1a9ae20663f0711ed6e4", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.30
[INFO] [stderr]    Compiling bit_field v0.10.1
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]    Compiling x86_64 v0.14.6
[INFO] [stderr]    Compiling volatile v0.4.4
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]    Compiling bootloader v0.9.19
[INFO] [stderr]    Compiling managed v0.7.2
[INFO] [stderr]    Compiling array-macro v2.1.0
[INFO] [stderr]    Compiling volatile v0.2.7
[INFO] [stderr]    Compiling bytes v1.1.0
[INFO] [stderr]    Compiling pc-keyboard v0.5.1
[INFO] [stderr]    Compiling lock_api v0.4.5
[INFO] [stderr]    Compiling bitvec v0.22.3
[INFO] [stderr]    Compiling rsdp v2.0.0
[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/lock_api-0.4.5/src/lib.rs:93:34
[INFO] [stdout]    |
[INFO] [stdout] 93 | #![cfg_attr(feature = "nightly", feature(const_fn_trait_bound))]
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[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/managed-0.7.2/src/lib.rs:2:67
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![cfg_attr(all(feature = "alloc", not(feature = "std")), feature(alloc))]
[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 `managed` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[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: build failed
[INFO] running `Command { std: "docker" "inspect" "708487c6e6d208444b4486e5a1b845dbbe46e801278d1a9ae20663f0711ed6e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "708487c6e6d208444b4486e5a1b845dbbe46e801278d1a9ae20663f0711ed6e4", kill_on_drop: false }`
[INFO] [stdout] 708487c6e6d208444b4486e5a1b845dbbe46e801278d1a9ae20663f0711ed6e4