[INFO] fetching crate rlinks 0.6.5...
[INFO] documenting rlinks-0.6.5 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate rlinks 0.6.5 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate rlinks 0.6.5 on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", 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-0/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-2020-08-29" "fetch" "--locked" "--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 futures-join-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded console v0.8.0
[INFO] [stderr]   Downloaded futures-select-macro-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded libnghttp2-sys v0.1.2
[INFO] [stderr]   Downloaded select v0.4.3
[INFO] [stderr]   Downloaded proc-macro-hack v0.5.9
[INFO] [stderr]   Downloaded curl v0.4.23
[INFO] [stderr]   Downloaded curl-sys v0.4.21
[INFO] [stderr]   Downloaded isahc v0.7.3
[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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3c25924e68972dcf7c95c1bd736972d311215d543e539547140437a1ab3a7e0f
[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" "3c25924e68972dcf7c95c1bd736972d311215d543e539547140437a1ab3a7e0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3c25924e68972dcf7c95c1bd736972d311215d543e539547140437a1ab3a7e0f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3c25924e68972dcf7c95c1bd736972d311215d543e539547140437a1ab3a7e0f", kill_on_drop: false }`
[INFO] [stdout] 3c25924e68972dcf7c95c1bd736972d311215d543e539547140437a1ab3a7e0f
[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" "RUSTDOCFLAGS=--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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9d3dd46fbc51191c3c045602cbd67c79c584747d0158fa4d40cb839a2acf14d8
[INFO] running `Command { std: "docker" "start" "-a" "9d3dd46fbc51191c3c045602cbd67c79c584747d0158fa4d40cb839a2acf14d8", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.62
[INFO] [stderr]    Compiling autocfg v0.1.6
[INFO] [stderr]     Checking cfg-if v0.1.9
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling proc-macro2 v1.0.2
[INFO] [stderr]    Compiling cc v1.0.42
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling pkg-config v0.3.15
[INFO] [stderr]    Compiling siphasher v0.2.3
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]    Compiling string_cache_shared v0.3.0
[INFO] [stderr]    Compiling getrandom v0.1.11
[INFO] [stderr]    Compiling ryu v1.0.0
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking smallvec v0.6.10
[INFO] [stderr]     Checking new_debug_unreachable v1.0.3
[INFO] [stderr]    Compiling itoa v0.4.4
[INFO] [stderr]     Checking mac v0.1.1
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]     Checking regex-syntax v0.6.12
[INFO] [stderr]     Checking precomputed-hash v0.1.1
[INFO] [stderr]     Checking unicode-width v0.1.6
[INFO] [stderr]     Checking scopeguard v1.0.0
[INFO] [stderr]    Compiling curl v0.4.23
[INFO] [stderr]     Checking bit-vec v0.5.1
[INFO] [stderr]     Checking fnv v1.0.6
[INFO] [stderr]     Checking quick-error v1.2.2
[INFO] [stderr]    Compiling isahc v0.7.3
[INFO] [stderr]     Checking termcolor v1.0.5
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]     Checking c2-chacha v0.2.2
[INFO] [stderr]    Compiling phf_shared v0.7.24
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futf v0.1.4
[INFO] [stderr]     Checking unicode-normalization v0.1.8
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking lock_api v0.3.1
[INFO] [stderr]     Checking bit-set v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling num-traits v0.2.8
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]     Checking humantime v1.2.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking tendril v0.4.1
[INFO] [stderr]     Checking phf v0.7.24
[INFO] [stderr]     Checking crossbeam-channel v0.3.9
[INFO] [stderr]     Checking sluice v0.4.2
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]     Checking aho-corasick v0.7.6
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking iovec v0.1.2
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking atty v0.2.13
[INFO] [stderr]     Checking time v0.1.42
[INFO] [stderr]     Checking parking_lot_core v0.6.2
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking num_cpus v1.10.1
[INFO] [stderr]     Checking socket2 v0.3.11
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking idna v0.2.0
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]    Compiling openssl-sys v0.9.49
[INFO] [stderr]    Compiling libnghttp2-sys v0.1.2
[INFO] [stderr]    Compiling libz-sys v1.0.25
[INFO] [stderr]    Compiling curl-sys v0.4.21
[INFO] [stderr]     Checking parking_lot v0.9.0
[INFO] [stderr]     Checking http v0.1.18
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]     Checking url v2.1.0
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]     Checking regex v1.3.1
[INFO] [stderr]     Checking chrono v0.4.9
[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]     Checking console v0.8.0
[INFO] [stderr]     Checking env_logger v0.6.2
[INFO] [stderr]     Checking indicatif v0.11.0
[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]     Checking 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]   |                                      ^^^^^^^^^^^^^^^^^^^^
[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`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "9d3dd46fbc51191c3c045602cbd67c79c584747d0158fa4d40cb839a2acf14d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9d3dd46fbc51191c3c045602cbd67c79c584747d0158fa4d40cb839a2acf14d8", kill_on_drop: false }`
[INFO] [stdout] 9d3dd46fbc51191c3c045602cbd67c79c584747d0158fa4d40cb839a2acf14d8