[INFO] fetching crate bottle 1.1.0-alpha...
[INFO] testing bottle-1.1.0-alpha against 1.60.0 for beta-1.61-1
[INFO] extracting crate bottle 1.1.0-alpha into /workspace/builds/worker-31/source
[INFO] validating manifest of crates.io crate bottle 1.1.0-alpha on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate bottle 1.1.0-alpha
[INFO] finished tweaking crates.io crate bottle 1.1.0-alpha
[INFO] tweaked toml for crates.io crate bottle 1.1.0-alpha written to /workspace/builds/worker-31/source/Cargo.toml
[INFO] crate crates.io crate bottle 1.1.0-alpha already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded crossbeam-channel v0.4.2
[INFO] [stderr]   Downloaded smallvec v1.3.0
[INFO] [stderr]   Downloaded parking_lot_core v0.7.1
[INFO] [stderr]   Downloaded libc v0.2.68
[INFO] [stderr]   Downloaded async-attributes v1.1.1
[INFO] [stderr]   Downloaded futures-io v0.3.4
[INFO] [stderr]   Downloaded async-task v1.3.1
[INFO] [stderr]   Downloaded log v0.4.8
[INFO] [stderr]   Downloaded net2 v0.2.33
[INFO] [stderr]   Downloaded memoffset v0.5.4
[INFO] [stderr]   Downloaded autocfg v1.0.0
[INFO] [stderr]   Downloaded hermit-abi v0.1.10
[INFO] [stderr]   Downloaded kv-log-macro v1.0.4
[INFO] [stderr]   Downloaded once_cell v1.3.1
[INFO] [stderr]   Downloaded async-std v1.5.0
[INFO] [stderr]   Downloaded redox_syscall v0.1.56
[INFO] [stderr]   Downloaded futures-timer v2.0.2
[INFO] [stderr]   Downloaded mio v0.6.21
[INFO] [stderr]   Downloaded mio-uds v0.6.7
[INFO] [stderr]   Downloaded num_cpus v1.12.0
[INFO] [stderr]   Downloaded pin-project-lite v0.1.4
[INFO] [stderr]   Downloaded crossbeam-queue v0.2.1
[INFO] [stderr]   Downloaded futures-executor v0.3.4
[INFO] [stderr]   Downloaded futures-channel v0.3.4
[INFO] [stderr]   Downloaded futures-core v0.3.4
[INFO] [stderr]   Downloaded futures-macro v0.3.4
[INFO] [stderr]   Downloaded futures-sink v0.3.4
[INFO] [stderr]   Downloaded futures-task v0.3.4
[INFO] [stderr]   Downloaded pin-utils v0.1.0-alpha.4
[INFO] [stderr]   Downloaded proc-macro-nested v0.1.4
[INFO] [stderr]   Downloaded futures-util v0.3.4
[INFO] [stderr]   Downloaded futures v0.3.4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0e580e5221c57745468484161fba4ea986a70d179a62e1bd7a149e94bda6e2cd
[INFO] running `Command { std: "docker" "start" "-a" "0e580e5221c57745468484161fba4ea986a70d179a62e1bd7a149e94bda6e2cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0e580e5221c57745468484161fba4ea986a70d179a62e1bd7a149e94bda6e2cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0e580e5221c57745468484161fba4ea986a70d179a62e1bd7a149e94bda6e2cd", kill_on_drop: false }`
[INFO] [stdout] 0e580e5221c57745468484161fba4ea986a70d179a62e1bd7a149e94bda6e2cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ab3e299183a3f99ec1151bbd89c4965b02b0e566224831e01d4ad92ac2a6336e
[INFO] running `Command { std: "docker" "start" "-a" "ab3e299183a3f99ec1151bbd89c4965b02b0e566224831e01d4ad92ac2a6336e", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.10
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.17
[INFO] [stderr]    Compiling proc-macro-nested v0.1.4
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling proc-macro-hack v0.5.15
[INFO] [stderr]    Compiling futures-sink v0.3.4
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling libc v0.2.68
[INFO] [stderr]    Compiling futures-core v0.3.4
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling pin-utils v0.1.0-alpha.4
[INFO] [stderr]    Compiling slab v0.4.2
[INFO] [stderr]    Compiling futures-task v0.3.4
[INFO] [stderr]    Compiling futures-io v0.3.4
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling smallvec v1.3.0
[INFO] [stderr]    Compiling static_assertions v1.1.0
[INFO] [stderr]    Compiling lock_api v0.3.4
[INFO] [stderr]    Compiling futures-channel v0.3.4
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling quote v1.0.3
[INFO] [stderr]    Compiling parking_lot_core v0.7.1
[INFO] [stderr]    Compiling parking_lot v0.10.2
[INFO] [stderr]    Compiling crossbeam-queue v0.2.1
[INFO] [stderr]    Compiling futures-macro v0.3.4
[INFO] [stderr]    Compiling futures-util v0.3.4
[INFO] [stderr]    Compiling futures-executor v0.3.4
[INFO] [stderr]    Compiling futures v0.3.4
[INFO] [stderr]    Compiling bottle v1.1.0-alpha (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:1:1
[INFO] [stdout]    |
[INFO] [stdout] 1  | / #![feature(
[INFO] [stdout] 2  | |     // To allow the use of `Receiver<Self>` as `self` type.
[INFO] [stdout] 3  | |     arbitrary_self_types,
[INFO] [stdout] 4  | |
[INFO] [stdout] ...  |
[INFO] [stdout] 20 | |     weak_into_raw
[INFO] [stdout] 21 | | )]
[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 `bottle` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "ab3e299183a3f99ec1151bbd89c4965b02b0e566224831e01d4ad92ac2a6336e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ab3e299183a3f99ec1151bbd89c4965b02b0e566224831e01d4ad92ac2a6336e", kill_on_drop: false }`
[INFO] [stdout] ab3e299183a3f99ec1151bbd89c4965b02b0e566224831e01d4ad92ac2a6336e