[INFO] fetching crate snail_image_confuse 0.1.0...
[INFO] documenting snail_image_confuse-0.1.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate snail_image_confuse 0.1.0 into /workspace/builds/worker-37/source
[INFO] validating manifest of crates.io crate snail_image_confuse 0.1.0 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 crates.io crate snail_image_confuse 0.1.0
[INFO] finished tweaking crates.io crate snail_image_confuse 0.1.0
[INFO] tweaked toml for crates.io crate snail_image_confuse 0.1.0 written to /workspace/builds/worker-37/source/Cargo.toml
[INFO] crate crates.io crate snail_image_confuse 0.1.0 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]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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] 25a022ee650264fef2e815b31527b52db3cda981c5c6a349028f0f6e7eac8058
[INFO] running `Command { std: "docker" "start" "-a" "25a022ee650264fef2e815b31527b52db3cda981c5c6a349028f0f6e7eac8058", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "25a022ee650264fef2e815b31527b52db3cda981c5c6a349028f0f6e7eac8058", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "25a022ee650264fef2e815b31527b52db3cda981c5c6a349028f0f6e7eac8058", kill_on_drop: false }`
[INFO] [stdout] 25a022ee650264fef2e815b31527b52db3cda981c5c6a349028f0f6e7eac8058
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-37/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] 142fb52f0f9c3866c872dbb7fb63545a75a42351502722303aed77c4b63e01aa
[INFO] running `Command { std: "docker" "start" "-a" "142fb52f0f9c3866c872dbb7fb63545a75a42351502722303aed77c4b63e01aa", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling libc v0.2.108
[INFO] [stderr]    Compiling crossbeam-utils v0.8.5
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.5
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling rayon-core v1.9.1
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]     Checking adler32 v1.2.0
[INFO] [stderr]    Compiling crc32fast v1.2.2
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking weezl v0.1.5
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking byteorder v1.4.3
[INFO] [stderr]     Checking color_quant v1.1.0
[INFO] [stderr]     Checking scoped_threadpool v0.1.9
[INFO] [stderr]     Checking bytemuck v1.7.2
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking log v0.4.14
[INFO] [stderr]     Checking miniz_oxide v0.3.7
[INFO] [stderr]     Checking deflate v0.8.6
[INFO] [stderr]     Checking gif v0.11.3
[INFO] [stderr]    Compiling memoffset v0.6.4
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling rayon v1.5.1
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.3.2
[INFO] [stderr]     Checking crossbeam-channel v0.5.1
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking png v0.16.8
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking crossbeam-deque v0.8.1
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]     Checking pretty_env_logger v0.4.0
[INFO] [stderr]     Checking jpeg-decoder v0.1.22
[INFO] [stderr]     Checking tiff v0.6.1
[INFO] [stderr]     Checking image v0.23.14
[INFO] [stderr]  Documenting snail_image_confuse 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:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(generators, generator_trait)]
[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 `snail_image_confuse`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name snail_image_confuse src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=4ef5885d2ebd6177 -L dependency=/opt/rustwide/target/debug/deps --extern clap=/opt/rustwide/target/debug/deps/libclap-1c1cc6cdbe53503e.rmeta --extern image=/opt/rustwide/target/debug/deps/libimage-0a5d9dcbea4ab38d.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-1e3c371ab90a7930.rmeta --extern pretty_env_logger=/opt/rustwide/target/debug/deps/libpretty_env_logger-69dd37074dfcd20a.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "142fb52f0f9c3866c872dbb7fb63545a75a42351502722303aed77c4b63e01aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "142fb52f0f9c3866c872dbb7fb63545a75a42351502722303aed77c4b63e01aa", kill_on_drop: false }`
[INFO] [stdout] 142fb52f0f9c3866c872dbb7fb63545a75a42351502722303aed77c4b63e01aa