[INFO] cloning repository https://github.com/piedoom/unsplash-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/piedoom/unsplash-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpiedoom%2Funsplash-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpiedoom%2Funsplash-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a49448a6270c80ed779472ebdbda57345a6fbf3b
[INFO] documenting piedoom/unsplash-rs against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fpiedoom%2Funsplash-rs" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/piedoom/unsplash-rs 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 git repo https://github.com/piedoom/unsplash-rs
[INFO] finished tweaking git repo https://github.com/piedoom/unsplash-rs
[INFO] tweaked toml for git repo https://github.com/piedoom/unsplash-rs written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/piedoom/unsplash-rs 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] 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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 2eef1d1fb04ece69828549fdaeae3e6fe861fa67bb6e5b4a839121e8a88a2acd
[INFO] running `Command { std: "docker" "start" "-a" "2eef1d1fb04ece69828549fdaeae3e6fe861fa67bb6e5b4a839121e8a88a2acd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2eef1d1fb04ece69828549fdaeae3e6fe861fa67bb6e5b4a839121e8a88a2acd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2eef1d1fb04ece69828549fdaeae3e6fe861fa67bb6e5b4a839121e8a88a2acd", kill_on_drop: false }`
[INFO] [stdout] 2eef1d1fb04ece69828549fdaeae3e6fe861fa67bb6e5b4a839121e8a88a2acd
[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] [stdout] bd0e0cb5e14cccf15b403056a18663f116a87d088382120b43e1b2fc34f88bc5
[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" "bd0e0cb5e14cccf15b403056a18663f116a87d088382120b43e1b2fc34f88bc5", 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]     Checking byteorder v1.2.3
[INFO] [stderr]     Checking futures v0.1.23
[INFO] [stderr]     Checking slab v0.4.0
[INFO] [stderr]     Checking lazycell v0.6.0
[INFO] [stderr]    Compiling rayon-core v1.4.1
[INFO] [stderr]    Compiling num-integer v0.1.39
[INFO] [stderr]    Compiling rayon v1.0.2
[INFO] [stderr]    Compiling httparse v1.3.2
[INFO] [stderr]     Checking itoa v0.4.2
[INFO] [stderr]     Checking either v1.5.0
[INFO] [stderr]     Checking indexmap v1.0.1
[INFO] [stderr]     Checking string v0.1.1
[INFO] [stderr]     Checking arrayvec v0.4.7
[INFO] [stderr]     Checking log v0.4.3
[INFO] [stderr]     Checking iovec v0.1.2
[INFO] [stderr]     Checking num_cpus v1.8.0
[INFO] [stderr]     Checking crossbeam-utils v0.3.2
[INFO] [stderr]     Checking crossbeam-utils v0.2.2
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]    Compiling syn v0.14.5
[INFO] [stderr]     Checking bytes v0.4.9
[INFO] [stderr]     Checking deflate v0.7.18
[INFO] [stderr]     Checking crossbeam-epoch v0.4.3
[INFO] [stderr]     Checking crossbeam-epoch v0.3.1
[INFO] [stderr]     Checking mio v0.6.15
[INFO] [stderr]     Checking crossbeam-deque v0.2.0
[INFO] [stderr]     Checking crossbeam-deque v0.3.1
[INFO] [stderr]     Checking num-iter v0.1.37
[INFO] [stderr]     Checking num-rational v0.1.42
[INFO] [stderr]     Checking http v0.1.8
[INFO] [stderr]     Checking png v0.12.0
[INFO] [stderr]     Checking tokio-io v0.1.7
[INFO] [stderr]     Checking tokio-executor v0.1.2
[INFO] [stderr]     Checking want v0.0.6
[INFO] [stderr]     Checking futures-cpupool v0.1.8
[INFO] [stderr]     Checking tokio-threadpool v0.1.5
[INFO] [stderr]     Checking tokio-timer v0.2.4
[INFO] [stderr]     Checking tokio-reactor v0.1.2
[INFO] [stderr]     Checking tokio-codec v0.1.0
[INFO] [stderr]     Checking tokio-fs v0.1.2
[INFO] [stderr]    Compiling num-derive v0.2.2
[INFO] [stderr]     Checking tokio-udp v0.1.1
[INFO] [stderr]     Checking tokio-tcp v0.1.0
[INFO] [stderr]     Checking jpeg-decoder v0.1.15
[INFO] [stderr]     Checking h2 v0.1.10
[INFO] [stderr]     Checking tokio v0.1.7
[INFO] [stderr]     Checking image v0.19.0
[INFO] [stderr]     Checking hyper v0.12.7
[INFO] [stderr]  Documenting unsplash v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(rust_2018_preview)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `unsplash`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name unsplash src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern hyper=/opt/rustwide/target/debug/deps/libhyper-0ad0b5be2ed1d9ee.rmeta --extern image=/opt/rustwide/target/debug/deps/libimage-04ae61df7cee40f4.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "bd0e0cb5e14cccf15b403056a18663f116a87d088382120b43e1b2fc34f88bc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bd0e0cb5e14cccf15b403056a18663f116a87d088382120b43e1b2fc34f88bc5", kill_on_drop: false }`
[INFO] [stdout] bd0e0cb5e14cccf15b403056a18663f116a87d088382120b43e1b2fc34f88bc5