[INFO] fetching crate rlinks 0.6.5...
[INFO] testing rlinks-0.6.5 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate rlinks 0.6.5 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate rlinks 0.6.5 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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-13/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" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded select v0.4.3
[INFO] [stderr]   Downloaded cc v1.0.42
[INFO] [stderr]   Downloaded lock_api v0.3.1
[INFO] [stderr]   Downloaded futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded console v0.8.0
[INFO] [stderr]   Downloaded getrandom v0.1.11
[INFO] [stderr]   Downloaded libnghttp2-sys v0.1.2
[INFO] [stderr]   Downloaded proc-macro-hack v0.5.9
[INFO] [stderr]   Downloaded string_cache v0.7.3
[INFO] [stderr]   Downloaded futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded curl-sys v0.4.21
[INFO] [stderr]   Downloaded proc-macro2 v1.0.2
[INFO] [stderr]   Downloaded curl v0.4.23
[INFO] [stderr]   Downloaded isahc v0.7.3
[INFO] [stderr]   Downloaded string_cache_codegen v0.4.2
[INFO] [stderr]   Downloaded url v2.1.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1ee7d69157f2c5e9f4a394ac44357f8eb5f4d18d4d256f9d0c1dd88151064d31
[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" "1ee7d69157f2c5e9f4a394ac44357f8eb5f4d18d4d256f9d0c1dd88151064d31", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1ee7d69157f2c5e9f4a394ac44357f8eb5f4d18d4d256f9d0c1dd88151064d31", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1ee7d69157f2c5e9f4a394ac44357f8eb5f4d18d4d256f9d0c1dd88151064d31", kill_on_drop: false }`
[INFO] [stdout] 1ee7d69157f2c5e9f4a394ac44357f8eb5f4d18d4d256f9d0c1dd88151064d31
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9237181189c1bae1c66caf5612c411786432f9b939fa6e75d7d64a0c956d774e
[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" "9237181189c1bae1c66caf5612c411786432f9b939fa6e75d7d64a0c956d774e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.2
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling new_debug_unreachable v1.0.3
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling curl v0.4.23
[INFO] [stderr]    Compiling bit-vec v0.5.1
[INFO] [stderr]    Compiling isahc v0.7.3
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling num-traits v0.2.8
[INFO] [stderr]    Compiling curl-sys v0.4.21
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling lock_api v0.3.1
[INFO] [stderr]    Compiling futf v0.1.4
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling clicolors-control v1.0.1
[INFO] [stderr]    Compiling time v0.1.42
[INFO] [stderr]    Compiling termios v0.3.1
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling bit-set v0.5.1
[INFO] [stderr]    Compiling tendril v0.4.1
[INFO] [stderr]    Compiling rand_chacha v0.2.1
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling console v0.8.0
[INFO] [stderr]    Compiling rand v0.7.0
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling sluice v0.4.2
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling number_prefix v0.2.8
[INFO] [stderr]    Compiling indicatif v0.11.0
[INFO] [stderr]    Compiling phf_generator v0.7.24
[INFO] [stderr]    Compiling chrono v0.4.9
[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 proc-macro-hack v0.5.9
[INFO] [stderr]    Compiling serde_derive v1.0.99
[INFO] [stderr]    Compiling serde_json v1.0.40
[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]    Compiling html5ever v0.23.0
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta 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] [stderr]    Compiling markup5ever v0.8.1
[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" "9237181189c1bae1c66caf5612c411786432f9b939fa6e75d7d64a0c956d774e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9237181189c1bae1c66caf5612c411786432f9b939fa6e75d7d64a0c956d774e", kill_on_drop: false }`
[INFO] [stdout] 9237181189c1bae1c66caf5612c411786432f9b939fa6e75d7d64a0c956d774e