[INFO] cloning repository https://github.com/htrefil/multiman
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/htrefil/multiman" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhtrefil%2Fmultiman", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhtrefil%2Fmultiman'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ff727ef3d81c0ed05a5f5b82ad8d3832385b12bb
[INFO] documenting htrefil/multiman 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%2Fhtrefil%2Fmultiman" "/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/htrefil/multiman 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/htrefil/multiman
[INFO] finished tweaking git repo https://github.com/htrefil/multiman
[INFO] tweaked toml for git repo https://github.com/htrefil/multiman written to /workspace/builds/worker-19/source/Cargo.toml
[INFO] crate git repo https://github.com/htrefil/multiman 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 num-traits v0.2.9
[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] f957e0f324ae16d312e1301622b59ee2013e30371a1222a5231d8d76f8867272
[INFO] running `Command { std: "docker" "start" "-a" "f957e0f324ae16d312e1301622b59ee2013e30371a1222a5231d8d76f8867272", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f957e0f324ae16d312e1301622b59ee2013e30371a1222a5231d8d76f8867272", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f957e0f324ae16d312e1301622b59ee2013e30371a1222a5231d8d76f8867272", kill_on_drop: false }`
[INFO] [stdout] f957e0f324ae16d312e1301622b59ee2013e30371a1222a5231d8d76f8867272
[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] 6944a7669292f82881bed3e9e2aa7d1591288826f31767c2fcbd1c0c1336b43c
[INFO] running `Command { std: "docker" "start" "-a" "6944a7669292f82881bed3e9e2aa7d1591288826f31767c2fcbd1c0c1336b43c", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v0.1.7
[INFO] [stderr]    Compiling libc v0.2.65
[INFO] [stderr]    Compiling proc-macro2 v1.0.6
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling byteorder v1.3.2
[INFO] [stderr]     Checking scopeguard v1.0.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling syn v1.0.5
[INFO] [stderr]    Compiling rayon-core v1.7.0
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking adler32 v1.0.4
[INFO] [stderr]    Compiling crc32fast v1.2.0
[INFO] [stderr]     Checking lzw v0.10.0
[INFO] [stderr]    Compiling unicode-segmentation v1.3.0
[INFO] [stderr]     Checking unicode-width v0.1.6
[INFO] [stderr]     Checking color_quant v1.0.1
[INFO] [stderr]     Checking scoped_threadpool v0.1.9
[INFO] [stderr]    Compiling memoffset v0.5.3
[INFO] [stderr]     Checking inflate v0.4.5
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking gif v0.10.3
[INFO] [stderr]    Compiling crossbeam-utils v0.7.0
[INFO] [stderr]    Compiling num-traits v0.2.9
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.0
[INFO] [stderr]    Compiling num-integer v0.1.41
[INFO] [stderr]    Compiling num-iter v0.1.39
[INFO] [stderr]    Compiling num-rational v0.2.2
[INFO] [stderr]    Compiling num-complex v0.2.3
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]     Checking deflate v0.7.20
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling quote v1.0.2
[INFO] [stderr]     Checking num_cpus v1.11.1
[INFO] [stderr]     Checking atty v0.2.13
[INFO] [stderr]     Checking crossbeam-queue v0.2.1
[INFO] [stderr]     Checking clap v2.33.0
[INFO] [stderr]     Checking png v0.15.1
[INFO] [stderr]     Checking crossbeam-deque v0.7.2
[INFO] [stderr]     Checking rayon v1.3.0
[INFO] [stderr]    Compiling proc-macro-error v0.2.6
[INFO] [stderr]     Checking jpeg-decoder v0.1.16
[INFO] [stderr]    Compiling structopt-derive v0.3.3
[INFO] [stderr]     Checking tiff v0.3.1
[INFO] [stderr]     Checking image v0.22.3
[INFO] [stderr]     Checking structopt v0.3.3
[INFO] [stderr]  Documenting multiman 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(process_exitcode_placeholder)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `process_exitcode_placeholder`
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(process_exitcode_placeholder)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `multiman`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name multiman src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=c6617ec3194b0429 -L dependency=/opt/rustwide/target/debug/deps --extern image=/opt/rustwide/target/debug/deps/libimage-d8b8cebb88f269d1.rmeta --extern num_complex=/opt/rustwide/target/debug/deps/libnum_complex-3de20c1bc63c4df9.rmeta --extern num_cpus=/opt/rustwide/target/debug/deps/libnum_cpus-ff6d32007e8178fc.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-b9d09b0f8917737f.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "6944a7669292f82881bed3e9e2aa7d1591288826f31767c2fcbd1c0c1336b43c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6944a7669292f82881bed3e9e2aa7d1591288826f31767c2fcbd1c0c1336b43c", kill_on_drop: false }`
[INFO] [stdout] 6944a7669292f82881bed3e9e2aa7d1591288826f31767c2fcbd1c0c1336b43c