[INFO] fetching crate rlinks 0.6.5...
[INFO] checking rlinks-0.6.5 against 1.55.0 for beta-1.56-3
[INFO] extracting crate rlinks 0.6.5 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate rlinks 0.6.5 on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate rlinks 0.6.5
[INFO] finished tweaking crates.io crate rlinks 0.6.5
[INFO] tweaked toml for crates.io crate rlinks 0.6.5 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate crates.io crate rlinks 0.6.5 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bitflags v1.1.0
[INFO] [stderr]   Downloaded ryu v1.0.0
[INFO] [stderr]   Downloaded serde v1.0.99
[INFO] [stderr]   Downloaded pin-utils v0.1.0-alpha.4
[INFO] [stderr]   Downloaded futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded humantime v1.2.0
[INFO] [stderr]   Downloaded getrandom v0.1.11
[INFO] [stderr]   Downloaded bit-vec v0.5.1
[INFO] [stderr]   Downloaded vcpkg v0.2.7
[INFO] [stderr]   Downloaded curl v0.4.23
[INFO] [stderr]   Downloaded cc v1.0.42
[INFO] [stderr]   Downloaded schannel v0.1.15
[INFO] [stderr]   Downloaded futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded pkg-config v0.3.15
[INFO] [stderr]   Downloaded scopeguard v1.0.0
[INFO] [stderr]   Downloaded futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded proc-macro-nested v0.1.3
[INFO] [stderr]   Downloaded rand v0.7.0
[INFO] [stderr]   Downloaded cfg-if v0.1.9
[INFO] [stderr]   Downloaded serde_derive v1.0.99
[INFO] [stderr]   Downloaded proc-macro2 v1.0.2
[INFO] [stderr]   Downloaded wasi v0.5.0
[INFO] [stderr]   Downloaded string_cache_codegen v0.4.2
[INFO] [stderr]   Downloaded futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded serde_json v1.0.40
[INFO] [stderr]   Downloaded iovec v0.1.2
[INFO] [stderr]   Downloaded url v2.1.0
[INFO] [stderr]   Downloaded http v0.1.18
[INFO] [stderr]   Downloaded futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded select v0.4.3
[INFO] [stderr]   Downloaded curl-sys v0.4.21
[INFO] [stderr]   Downloaded futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded indicatif v0.11.0
[INFO] [stderr]   Downloaded proc-macro-hack v0.5.9
[INFO] [stderr]   Downloaded console v0.8.0
[INFO] [stderr]   Downloaded isahc v0.7.3
[INFO] [stderr]   Downloaded string_cache v0.7.3
[INFO] [stderr]   Downloaded bit-set v0.5.1
[INFO] [stderr]   Downloaded number_prefix v0.2.8
[INFO] [stderr]   Downloaded lock_api v0.3.1
[INFO] [stderr]   Downloaded socket2 v0.3.11
[INFO] [stderr]   Downloaded openssl-sys v0.9.49
[INFO] [stderr]   Downloaded futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded libnghttp2-sys v0.1.2
[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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7037dc3eae6973b56627a968d8eff15a6b782e1de67cd90d2d8aa46479baefac
[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" "7037dc3eae6973b56627a968d8eff15a6b782e1de67cd90d2d8aa46479baefac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7037dc3eae6973b56627a968d8eff15a6b782e1de67cd90d2d8aa46479baefac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7037dc3eae6973b56627a968d8eff15a6b782e1de67cd90d2d8aa46479baefac", kill_on_drop: false }`
[INFO] [stdout] 7037dc3eae6973b56627a968d8eff15a6b782e1de67cd90d2d8aa46479baefac
[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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0acaa22d37aa34dd721dda911fc856e997466099d088ce2877195ca161eea581
[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" "0acaa22d37aa34dd721dda911fc856e997466099d088ce2877195ca161eea581", 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]    Compiling proc-macro2 v1.0.2
[INFO] [stderr]    Compiling cc v1.0.42
[INFO] [stderr]    Compiling getrandom v0.1.11
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling proc-macro-nested v0.1.3
[INFO] [stderr]    Compiling itoa v0.4.4
[INFO] [stderr]     Checking new_debug_unreachable v1.0.3
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling curl v0.4.23
[INFO] [stderr]    Compiling isahc v0.7.3
[INFO] [stderr]     Checking quick-error v1.2.2
[INFO] [stderr]     Checking bit-vec v0.5.1
[INFO] [stderr]     Checking termcolor v1.0.5
[INFO] [stderr]     Checking unicode-normalization v0.1.8
[INFO] [stderr]     Checking lock_api v0.3.1
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]     Checking crossbeam-channel v0.3.9
[INFO] [stderr]    Compiling ryu v1.0.0
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking socket2 v0.3.11
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]     Checking futf v0.1.4
[INFO] [stderr]     Checking humantime v1.2.0
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking bit-set v0.5.1
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking http v0.1.18
[INFO] [stderr]    Compiling html5ever v0.23.0
[INFO] [stderr]     Checking console v0.8.0
[INFO] [stderr]     Checking parking_lot_core v0.6.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking tendril v0.4.1
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking parking_lot v0.9.0
[INFO] [stderr]     Checking sluice v0.4.2
[INFO] [stderr]     Checking idna v0.2.0
[INFO] [stderr]    Compiling openssl-sys v0.9.49
[INFO] [stderr]    Compiling libz-sys v1.0.25
[INFO] [stderr]    Compiling libnghttp2-sys v0.1.2
[INFO] [stderr]    Compiling curl-sys v0.4.21
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking indicatif v0.11.0
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]     Checking url v2.1.0
[INFO] [stderr]    Compiling phf_generator v0.7.24
[INFO] [stderr]    Compiling string_cache_codegen v0.4.2
[INFO] [stderr]    Compiling phf_codegen v0.7.24
[INFO] [stderr]    Compiling string_cache v0.7.3
[INFO] [stderr]    Compiling serde_json v1.0.40
[INFO] [stderr]    Compiling proc-macro-hack v0.5.9
[INFO] [stderr]    Compiling serde_derive v1.0.99
[INFO] [stderr]    Compiling futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.18
[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/futures-util-preview-0.3.0-alpha.18/src/lib.rs:4:38
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![cfg_attr(feature = "async-await", feature(async_await))]
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `async_await` has been stable since 1.39.0 and no longer requires an attribute to enable
[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 `futures-util-preview` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "0acaa22d37aa34dd721dda911fc856e997466099d088ce2877195ca161eea581", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0acaa22d37aa34dd721dda911fc856e997466099d088ce2877195ca161eea581", kill_on_drop: false }`
[INFO] [stdout] 0acaa22d37aa34dd721dda911fc856e997466099d088ce2877195ca161eea581
