[INFO] fetching crate unsplash-rs 0.1.1...
[INFO] documenting unsplash-rs-0.1.1 against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] extracting crate unsplash-rs 0.1.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate unsplash-rs 0.1.1 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 unsplash-rs 0.1.1
[INFO] finished tweaking crates.io crate unsplash-rs 0.1.1
[INFO] tweaked toml for crates.io crate unsplash-rs 0.1.1 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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]  Downloading crates ...
[INFO] [stderr]   Downloaded serde_url_params v0.1.1
[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" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 446354e23e9fd3a1b842d81fab6c5baf7c1bedbcca20f09a7f00f6dd27071a1c
[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" "446354e23e9fd3a1b842d81fab6c5baf7c1bedbcca20f09a7f00f6dd27071a1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "446354e23e9fd3a1b842d81fab6c5baf7c1bedbcca20f09a7f00f6dd27071a1c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "446354e23e9fd3a1b842d81fab6c5baf7c1bedbcca20f09a7f00f6dd27071a1c", kill_on_drop: false }`
[INFO] [stdout] 446354e23e9fd3a1b842d81fab6c5baf7c1bedbcca20f09a7f00f6dd27071a1c
[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" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d3ac5d9cc2582897032c428b5382ebd1303ddc90f9a7246b7c321865fa950a78
[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" "d3ac5d9cc2582897032c428b5382ebd1303ddc90f9a7246b7c321865fa950a78", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking serde_url_params v0.1.1
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]     Checking hyper v0.12.35
[INFO] [stderr]  Documenting unsplash-rs v0.1.1 (/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(option_replace)]
[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-rs`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name unsplash_rs 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 chrono=/opt/rustwide/target/debug/deps/libchrono-14db07e4a62b1a16.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-56dd397d7044e9d2.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-f6a782863e1804d0.rmeta --extern hyper=/opt/rustwide/target/debug/deps/libhyper-d15f63717fc734e8.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-7a83814764f365af.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-db88f49d9e5662e7.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-8b25aaf2e71705fc.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-ec5e695d7e4b5284.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-3a89c57880b62507.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-7b195ede6b83e119.rmeta --extern serde_url_params=/opt/rustwide/target/debug/deps/libserde_url_params-ac197cf9d2ee8eb9.rmeta --cap-lints=warn --crate-version 0.1.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "d3ac5d9cc2582897032c428b5382ebd1303ddc90f9a7246b7c321865fa950a78", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d3ac5d9cc2582897032c428b5382ebd1303ddc90f9a7246b7c321865fa950a78", kill_on_drop: false }`
[INFO] [stdout] d3ac5d9cc2582897032c428b5382ebd1303ddc90f9a7246b7c321865fa950a78