[INFO] cloning repository https://github.com/jaupe/memson
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jaupe/memson" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjaupe%2Fmemson", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjaupe%2Fmemson'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6ae6aa3ff122115a651c5d361afe5def073a1afb
[INFO] documenting jaupe/memson 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%2Fjaupe%2Fmemson" "/workspace/builds/worker-26/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-26/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jaupe/memson 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/jaupe/memson
[INFO] finished tweaking git repo https://github.com/jaupe/memson
[INFO] tweaked toml for git repo https://github.com/jaupe/memson written to /workspace/builds/worker-26/source/Cargo.toml
[INFO] crate git repo https://github.com/jaupe/memson 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 quote v1.0.5
[INFO] [stderr]   Downloaded proc-macro2 v1.0.13
[INFO] [stderr]   Downloaded assert_approx_eq v1.1.0
[INFO] [stderr]   Downloaded pin-project-internal v0.4.16
[INFO] [stderr]   Downloaded pin-project v0.4.16
[INFO] [stderr]   Downloaded syn v1.0.22
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/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] b174900bf0527a18f64f07f6a8beb2943304de5f71cf06fd249051b6d8a574b6
[INFO] running `Command { std: "docker" "start" "-a" "b174900bf0527a18f64f07f6a8beb2943304de5f71cf06fd249051b6d8a574b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b174900bf0527a18f64f07f6a8beb2943304de5f71cf06fd249051b6d8a574b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b174900bf0527a18f64f07f6a8beb2943304de5f71cf06fd249051b6d8a574b6", kill_on_drop: false }`
[INFO] [stdout] b174900bf0527a18f64f07f6a8beb2943304de5f71cf06fd249051b6d8a574b6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-26/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] a5e51caaab1cc897c26ba10b9889c716233764e44062161d4398b92ee56a775f
[INFO] running `Command { std: "docker" "start" "-a" "a5e51caaab1cc897c26ba10b9889c716233764e44062161d4398b92ee56a775f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.13
[INFO] [stderr]    Compiling syn v1.0.22
[INFO] [stderr]    Compiling libc v0.2.70
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]     Checking futures-core v0.3.5
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]     Checking futures-sink v0.3.5
[INFO] [stderr]    Compiling proc-macro-nested v0.1.4
[INFO] [stderr]     Checking once_cell v1.4.0
[INFO] [stderr]    Compiling proc-macro-hack v0.5.15
[INFO] [stderr]    Compiling serde v1.0.110
[INFO] [stderr]     Checking arc-swap v0.4.6
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking futures-io v0.3.5
[INFO] [stderr]    Compiling ryu v1.0.4
[INFO] [stderr]     Checking fnv v1.0.7
[INFO] [stderr]     Checking bytes v0.5.4
[INFO] [stderr]     Checking unicode-width v0.1.7
[INFO] [stderr]     Checking pin-project-lite v0.1.5
[INFO] [stderr]     Checking itoa v0.4.5
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking futures-task v0.3.5
[INFO] [stderr]     Checking futures-channel v0.3.5
[INFO] [stderr]    Compiling quote v1.0.5
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.34
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking signal-hook-registry v1.2.0
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.1
[INFO] [stderr]     Checking mio v0.6.22
[INFO] [stderr]     Checking mio-uds v0.6.8
[INFO] [stderr]    Compiling pin-project-internal v0.4.16
[INFO] [stderr]    Compiling futures-macro v0.3.5
[INFO] [stderr]    Compiling serde_derive v1.0.110
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]     Checking tokio v0.2.21
[INFO] [stderr]     Checking pin-project v0.4.16
[INFO] [stderr]     Checking futures-util v0.3.5
[INFO] [stderr]     Checking tokio-util v0.2.0
[INFO] [stderr]     Checking futures-executor v0.3.5
[INFO] [stderr]     Checking futures v0.3.5
[INFO] [stderr]     Checking serde_json v1.0.53
[INFO] [stderr]     Checking bincode v1.2.1
[INFO] [stderr]  Documenting memson v0.1.1 (/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(box_patterns)]
[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 `memson`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name memson src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=4f158911c46e0183 -L dependency=/opt/rustwide/target/debug/deps --extern bincode=/opt/rustwide/target/debug/deps/libbincode-93a3bb1a0bc8762a.rmeta --extern clap=/opt/rustwide/target/debug/deps/libclap-4b49328629d40e32.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-ce3d4fe85142e963.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-2300e5f92859063b.rmeta --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-e75fb044f3bc8a21.rmeta --extern tokio=/opt/rustwide/target/debug/deps/libtokio-71a22001a3c7e7f6.rmeta --extern tokio_util=/opt/rustwide/target/debug/deps/libtokio_util-e90c97c5b2048b67.rmeta --cap-lints=warn --crate-version 0.1.1` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "a5e51caaab1cc897c26ba10b9889c716233764e44062161d4398b92ee56a775f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5e51caaab1cc897c26ba10b9889c716233764e44062161d4398b92ee56a775f", kill_on_drop: false }`
[INFO] [stdout] a5e51caaab1cc897c26ba10b9889c716233764e44062161d4398b92ee56a775f