[INFO] cloning repository https://github.com/jlricon/rlinks
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jlricon/rlinks" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjlricon%2Frlinks", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjlricon%2Frlinks'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f39102c47e45b875a008756cdc87a590ff5f58c1
[INFO] documenting jlricon/rlinks against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjlricon%2Frlinks" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jlricon/rlinks on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jlricon/rlinks
[INFO] finished tweaking git repo https://github.com/jlricon/rlinks
[INFO] tweaked toml for git repo https://github.com/jlricon/rlinks written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/jlricon/rlinks already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 52d862d6f3b7aa134014dc201579b2869cb4570a9ef6e102ff89fdd7af8a3834
[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" "52d862d6f3b7aa134014dc201579b2869cb4570a9ef6e102ff89fdd7af8a3834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "52d862d6f3b7aa134014dc201579b2869cb4570a9ef6e102ff89fdd7af8a3834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52d862d6f3b7aa134014dc201579b2869cb4570a9ef6e102ff89fdd7af8a3834", kill_on_drop: false }`
[INFO] [stdout] 52d862d6f3b7aa134014dc201579b2869cb4570a9ef6e102ff89fdd7af8a3834
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 905d3bdf9bfd8b2539387cba85357b297535f46f310c77e81aed81382c5f8652
[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" "905d3bdf9bfd8b2539387cba85357b297535f46f310c77e81aed81382c5f8652", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.2
[INFO] [stderr]    Compiling cc v1.0.42
[INFO] [stderr]    Compiling pkg-config v0.3.15
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]    Compiling getrandom v0.1.11
[INFO] [stderr]     Checking ppv-lite86 v0.2.5
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[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]    Compiling num-integer v0.1.41
[INFO] [stderr]     Checking lock_api v0.3.1
[INFO] [stderr]     Checking crossbeam-channel v0.3.9
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking socket2 v0.3.11
[INFO] [stderr]     Checking termios v0.3.1
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking url v2.1.1
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking clap v2.33.1
[INFO] [stderr]     Checking regex v1.3.9
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking parking_lot_core v0.6.2
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling string_cache_codegen v0.4.2
[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 c2-chacha v0.2.2
[INFO] [stderr]     Checking http v0.1.18
[INFO] [stderr]     Checking chrono v0.4.9
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]    Compiling string_cache v0.7.3
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]    Compiling quote v1.0.2
[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 console v0.8.0
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]     Checking indicatif v0.11.0
[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 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]   |                                      ^^^^^^^^^^^^^^^^^^^^
[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`.
[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" "905d3bdf9bfd8b2539387cba85357b297535f46f310c77e81aed81382c5f8652", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "905d3bdf9bfd8b2539387cba85357b297535f46f310c77e81aed81382c5f8652", kill_on_drop: false }`
[INFO] [stdout] 905d3bdf9bfd8b2539387cba85357b297535f46f310c77e81aed81382c5f8652