[INFO] cloning repository https://github.com/risboo6909/aoc2020
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/risboo6909/aoc2020" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frisboo6909%2Faoc2020", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frisboo6909%2Faoc2020'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ca565fcdb401ac2e736693b78be702b7deb97bc6
[INFO] documenting risboo6909/aoc2020 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%2Frisboo6909%2Faoc2020" "/workspace/builds/worker-19/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-19/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/risboo6909/aoc2020 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/risboo6909/aoc2020
[INFO] finished tweaking git repo https://github.com/risboo6909/aoc2020
[INFO] tweaked toml for git repo https://github.com/risboo6909/aoc2020 written to /workspace/builds/worker-19/source/Cargo.toml
[INFO] crate git repo https://github.com/risboo6909/aoc2020 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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bytemuck v1.5.0
[INFO] [stderr]   Downloaded prefix-tree v0.5.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-19/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-19/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] 87e3309fa7729b89462486066afcc00aa1fc06699f9fe8313001f0cf578e475d
[INFO] running `Command { std: "docker" "start" "-a" "87e3309fa7729b89462486066afcc00aa1fc06699f9fe8313001f0cf578e475d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "87e3309fa7729b89462486066afcc00aa1fc06699f9fe8313001f0cf578e475d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "87e3309fa7729b89462486066afcc00aa1fc06699f9fe8313001f0cf578e475d", kill_on_drop: false }`
[INFO] [stdout] 87e3309fa7729b89462486066afcc00aa1fc06699f9fe8313001f0cf578e475d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-19/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-19/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] 5220623bfca348d0db708613b26ac185b26e436bd335cb2728c1ea635455482d
[INFO] running `Command { std: "docker" "start" "-a" "5220623bfca348d0db708613b26ac185b26e436bd335cb2728c1ea635455482d", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.85
[INFO] [stderr]    Compiling const_fn v0.4.5
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling rayon-core v1.9.0
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]     Checking object v0.23.0
[INFO] [stderr]     Checking adler32 v1.2.0
[INFO] [stderr]     Checking byteorder v1.4.2
[INFO] [stderr]     Checking weezl v0.1.4
[INFO] [stderr]     Checking color_quant v1.1.0
[INFO] [stderr]     Checking bytemuck v1.5.0
[INFO] [stderr]     Checking scoped_threadpool v0.1.9
[INFO] [stderr]     Checking permutohedron v0.2.4
[INFO] [stderr]     Checking prefix-tree v0.5.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling crossbeam-utils v0.8.1
[INFO] [stderr]    Compiling memoffset v0.6.1
[INFO] [stderr]    Compiling miniz_oxide v0.4.3
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-bigint v0.2.6
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling rayon v1.5.0
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling num-rational v0.3.2
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]     Checking addr2line v0.14.1
[INFO] [stderr]    Compiling crc32fast v1.2.1
[INFO] [stderr]     Checking itertools v0.8.2
[INFO] [stderr]     Checking itertools v0.10.0
[INFO] [stderr]     Checking miniz_oxide v0.3.7
[INFO] [stderr]    Compiling quote v1.0.8
[INFO] [stderr]     Checking gif v0.11.1
[INFO] [stderr]     Checking deflate v0.8.6
[INFO] [stderr]     Checking fxhash v0.2.1
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking backtrace v0.3.56
[INFO] [stderr]     Checking png v0.16.8
[INFO] [stderr]     Checking crossbeam-channel v0.4.4
[INFO] [stderr]     Checking crossbeam-queue v0.2.3
[INFO] [stderr]     Checking crossbeam-epoch v0.9.1
[INFO] [stderr]     Checking crossbeam-channel v0.5.0
[INFO] [stderr]     Checking colored v1.9.3
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking crossbeam-deque v0.8.0
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]     Checking utils v0.1.0 (/opt/rustwide/workdir/utils)
[INFO] [stderr]  Documenting utils v0.1.0 (/opt/rustwide/workdir/utils)
[INFO] [stderr]     Checking jpeg-decoder v0.1.22
[INFO] [stderr]     Checking tiff v0.6.1
[INFO] [stderr]     Checking image v0.23.13
[INFO] [stderr]  Documenting problems v0.1.0 (/opt/rustwide/workdir/problems)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> problems/src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(const_option)]
[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 `problems`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name problems problems/src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=ceb2ec8ca3e16035 -L dependency=/opt/rustwide/target/debug/deps --extern colored=/opt/rustwide/target/debug/deps/libcolored-32f280008142ebb3.rmeta --extern crossbeam=/opt/rustwide/target/debug/deps/libcrossbeam-fe77309c8936a101.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-d87d7a49637dc9a9.rmeta --extern fxhash=/opt/rustwide/target/debug/deps/libfxhash-306927363e223a46.rmeta --extern image=/opt/rustwide/target/debug/deps/libimage-bd1c28eed1ee1c5b.rmeta --extern itertools=/opt/rustwide/target/debug/deps/libitertools-6afed964e725cfad.rmeta --extern num_integer=/opt/rustwide/target/debug/deps/libnum_integer-f94efe5edad51941.rmeta --extern num_cpus=/opt/rustwide/target/debug/deps/libnum_cpus-85a1e9ea19979f4b.rmeta --extern permutohedron=/opt/rustwide/target/debug/deps/libpermutohedron-8daffba78bd82069.rmeta --extern prefix_tree=/opt/rustwide/target/debug/deps/libprefix_tree-306b9dc6583f69b4.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-e4cef298d1e4948c.rmeta --extern utils=/opt/rustwide/target/debug/deps/libutils-c1c98013aad9e8c2.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "5220623bfca348d0db708613b26ac185b26e436bd335cb2728c1ea635455482d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5220623bfca348d0db708613b26ac185b26e436bd335cb2728c1ea635455482d", kill_on_drop: false }`
[INFO] [stdout] 5220623bfca348d0db708613b26ac185b26e436bd335cb2728c1ea635455482d