[INFO] cloning repository https://github.com/vasily-kirichenko/failure_perf_issue
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/vasily-kirichenko/failure_perf_issue" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvasily-kirichenko%2Ffailure_perf_issue", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvasily-kirichenko%2Ffailure_perf_issue'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cd2d108809f03ee3a02636d8c184f5f731abe8c4
[INFO] documenting vasily-kirichenko/failure_perf_issue against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvasily-kirichenko%2Ffailure_perf_issue" "/workspace/builds/worker-16/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-16/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/vasily-kirichenko/failure_perf_issue on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/vasily-kirichenko/failure_perf_issue
[INFO] finished tweaking git repo https://github.com/vasily-kirichenko/failure_perf_issue
[INFO] tweaked toml for git repo https://github.com/vasily-kirichenko/failure_perf_issue written to /workspace/builds/worker-16/source/Cargo.toml
[INFO] crate git repo https://github.com/vasily-kirichenko/failure_perf_issue already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--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 relay v0.1.1
[INFO] [stderr]   Downloaded cc v1.0.12
[INFO] [stderr]   Downloaded hyper v0.11.25
[INFO] [stderr]   Downloaded bitflags v1.0.2
[INFO] [stderr]   Downloaded crossbeam-deque v0.3.0
[INFO] [stderr]   Downloaded tokio v0.1.5
[INFO] [stderr]   Downloaded tokio-timer v0.2.1
[INFO] [stderr]   Downloaded tokio-threadpool v0.1.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] eb26adfab192e363d8302e0f13662c5a861741abe9e5cf69b14fffad193a23e5
[INFO] running `Command { std: "docker" "start" "-a" "eb26adfab192e363d8302e0f13662c5a861741abe9e5cf69b14fffad193a23e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "eb26adfab192e363d8302e0f13662c5a861741abe9e5cf69b14fffad193a23e5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eb26adfab192e363d8302e0f13662c5a861741abe9e5cf69b14fffad193a23e5", kill_on_drop: false }`
[INFO] [stdout] eb26adfab192e363d8302e0f13662c5a861741abe9e5cf69b14fffad193a23e5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-16/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e2d32eb4f425dadbe9c2c0745a3c117c1eba3418a8d7ee92f68aaa4a1116c591
[INFO] running `Command { std: "docker" "start" "-a" "e2d32eb4f425dadbe9c2c0745a3c117c1eba3418a8d7ee92f68aaa4a1116c591", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking libc v0.2.40
[INFO] [stderr]     Checking cfg-if v0.1.2
[INFO] [stderr]     Checking futures v0.1.21
[INFO] [stderr]     Checking byteorder v1.2.2
[INFO] [stderr]     Checking slab v0.4.0
[INFO] [stderr]     Checking nodrop v0.1.12
[INFO] [stderr]     Checking lazycell v0.6.0
[INFO] [stderr]     Checking lazy_static v1.0.0
[INFO] [stderr]     Checking memoffset v0.2.1
[INFO] [stderr]     Checking scopeguard v0.3.3
[INFO] [stderr]    Compiling unicode-xid v0.0.4
[INFO] [stderr]    Compiling cc v1.0.12
[INFO] [stderr]    Compiling version_check v0.1.3
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling quote v0.3.15
[INFO] [stderr]     Checking scoped-tls v0.1.1
[INFO] [stderr]     Checking rustc-demangle v0.1.7
[INFO] [stderr]     Checking smallvec v0.2.1
[INFO] [stderr]     Checking slab v0.3.0
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[INFO] [stderr]     Checking log v0.4.1
[INFO] [stderr]     Checking crossbeam-utils v0.3.2
[INFO] [stderr]     Checking crossbeam-utils v0.2.2
[INFO] [stderr]    Compiling proc-macro2 v0.3.7
[INFO] [stderr]     Checking arrayvec v0.4.7
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[INFO] [stderr]     Checking log v0.3.9
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[INFO] [stderr]     Checking net2 v0.2.32
[INFO] [stderr]     Checking num_cpus v1.8.0
[INFO] [stderr]     Checking rand v0.4.2
[INFO] [stderr]     Checking time v0.1.39
[INFO] [stderr]    Compiling syn v0.11.11
[INFO] [stderr]     Checking crossbeam-epoch v0.4.1
[INFO] [stderr]    Compiling quote v0.5.2
[INFO] [stderr]    Compiling unicase v2.1.0
[INFO] [stderr]     Checking bytes v0.4.6
[INFO] [stderr]    Compiling syn v0.13.1
[INFO] [stderr]     Checking mio v0.6.14
[INFO] [stderr]     Checking crossbeam-deque v0.3.0
[INFO] [stderr]    Compiling backtrace-sys v0.1.16
[INFO] [stderr]     Checking rand v0.3.22
[INFO] [stderr]     Checking tokio-executor v0.1.2
[INFO] [stderr]     Checking tokio-io v0.1.6
[INFO] [stderr]     Checking tokio-service v0.1.0
[INFO] [stderr]     Checking relay v0.1.1
[INFO] [stderr]     Checking futures-cpupool v0.1.8
[INFO] [stderr]    Compiling synstructure v0.6.1
[INFO] [stderr]     Checking tokio-timer v0.2.1
[INFO] [stderr]     Checking tokio-threadpool v0.1.2
[INFO] [stderr]     Checking tokio-reactor v0.1.1
[INFO] [stderr]    Compiling serde_derive_internals v0.23.1
[INFO] [stderr]     Checking mime v0.3.5
[INFO] [stderr]     Checking tokio-tcp v0.1.0
[INFO] [stderr]     Checking tokio-udp v0.1.0
[INFO] [stderr]     Checking serde_json v1.0.16
[INFO] [stderr]    Compiling failure_derive v0.1.1
[INFO] [stderr]     Checking tokio v0.1.5
[INFO] [stderr]     Checking tokio-core v0.1.17
[INFO] [stderr]    Compiling serde_derive v1.0.43
[INFO] [stderr]     Checking tokio-proto v0.1.1
[INFO] [stderr]     Checking hyper v0.11.25
[INFO] [stderr]     Checking backtrace v0.3.6
[INFO] [stderr]     Checking failure v0.1.1
[INFO] [stderr]  Documenting failure_perf_issue v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_find_map)]
[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 document `failure_perf_issue`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type bin --crate-name failure_perf_issue src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=c4256277b6c68165 -L dependency=/opt/rustwide/target/debug/deps --extern failure=/opt/rustwide/target/debug/deps/libfailure-ad8ab8d1238d2847.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-eca66cf27e465c6b.rmeta --extern hyper=/opt/rustwide/target/debug/deps/libhyper-d5c2853a99b27b5e.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-757dbf34a5420405.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-745dd1cbf45c8419.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-cb23e78f667f15fc.rmeta --extern tokio_core=/opt/rustwide/target/debug/deps/libtokio_core-585c8e629703ab3e.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "e2d32eb4f425dadbe9c2c0745a3c117c1eba3418a8d7ee92f68aaa4a1116c591", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e2d32eb4f425dadbe9c2c0745a3c117c1eba3418a8d7ee92f68aaa4a1116c591", kill_on_drop: false }`
[INFO] [stdout] e2d32eb4f425dadbe9c2c0745a3c117c1eba3418a8d7ee92f68aaa4a1116c591