[INFO] cloning repository https://github.com/nyu-latency-labs/timer-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nyu-latency-labs/timer-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnyu-latency-labs%2Ftimer-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnyu-latency-labs%2Ftimer-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5d564d5d64a317aaecca6ac1a39d3aeeaf712539
[INFO] documenting nyu-latency-labs/timer-example against 1.54.0 for beta-1.55-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnyu-latency-labs%2Ftimer-example" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nyu-latency-labs/timer-example on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nyu-latency-labs/timer-example
[INFO] finished tweaking git repo https://github.com/nyu-latency-labs/timer-example
[INFO] tweaked toml for git repo https://github.com/nyu-latency-labs/timer-example written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/nyu-latency-labs/timer-example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 15589c8675cbef81b591a76bdfa0ce0042fcdf1a3576234fd15a2dd2aa83c9c2
[INFO] running `Command { std: "docker" "start" "-a" "15589c8675cbef81b591a76bdfa0ce0042fcdf1a3576234fd15a2dd2aa83c9c2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "15589c8675cbef81b591a76bdfa0ce0042fcdf1a3576234fd15a2dd2aa83c9c2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "15589c8675cbef81b591a76bdfa0ce0042fcdf1a3576234fd15a2dd2aa83c9c2", kill_on_drop: false }`
[INFO] [stdout] 15589c8675cbef81b591a76bdfa0ce0042fcdf1a3576234fd15a2dd2aa83c9c2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+1.54.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 9f53b732198b3112998483e06f3da1ed7e1a39a789e5555941b6c81d1f4f52a9
[INFO] running `Command { std: "docker" "start" "-a" "9f53b732198b3112998483e06f3da1ed7e1a39a789e5555941b6c81d1f4f52a9", kill_on_drop: false }`
[INFO] [stderr]     Checking futures v0.1.28
[INFO] [stderr]    Compiling proc-macro2 v1.0.1
[INFO] [stderr]    Compiling getrandom v0.1.11
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling serde v1.0.99
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling either v1.5.2
[INFO] [stderr]    Compiling bincode v1.1.4
[INFO] [stderr]     Checking humantime v1.2.0
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]     Checking parking_lot_core v0.6.2
[INFO] [stderr]    Compiling itertools v0.8.0
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.1
[INFO] [stderr]    Compiling tarpc-plugins v0.5.1 (https://github.com/nyu-latency-labs/tarpc.git#537446a5)
[INFO] [stderr]    Compiling tarpc-plugins v0.5.1 (https://github.com/nyu-latency-labs/tarpc.git?branch=master#537446a5)
[INFO] [stderr]     Checking once_cell v0.2.7
[INFO] [stderr]     Checking tokio-executor v0.1.8
[INFO] [stderr]     Checking tokio-io v0.1.12
[INFO] [stderr]     Checking tokio-sync v0.1.6
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking tokio-timer v0.2.11
[INFO] [stderr]     Checking tokio-threadpool v0.1.15
[INFO] [stderr]     Checking tokio-current-thread v0.1.6
[INFO] [stderr]     Checking rand v0.7.0
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]     Checking tokio-reactor v0.1.9
[INFO] [stderr]     Checking tokio-codec v0.1.1
[INFO] [stderr]     Checking tokio-fs v0.1.6
[INFO] [stderr]     Checking tokio-udp v0.1.3
[INFO] [stderr]     Checking tokio-uds v0.2.5
[INFO] [stderr]     Checking tokio-tcp v0.1.3
[INFO] [stderr]     Checking tokio v0.1.22
[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`
[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" "9f53b732198b3112998483e06f3da1ed7e1a39a789e5555941b6c81d1f4f52a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f53b732198b3112998483e06f3da1ed7e1a39a789e5555941b6c81d1f4f52a9", kill_on_drop: false }`
[INFO] [stdout] 9f53b732198b3112998483e06f3da1ed7e1a39a789e5555941b6c81d1f4f52a9
