[INFO] cloning repository https://github.com/JohnScience/nifti-example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/JohnScience/nifti-example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJohnScience%2Fnifti-example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJohnScience%2Fnifti-example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 34c6398900d443505c40fc2dacabaf976bb8a0aa
[INFO] documenting JohnScience/nifti-example against master#d7d9f15be205b45d44700e7ac33b4f79b91f9680 for pr-117450
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJohnScience%2Fnifti-example" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/JohnScience/nifti-example on toolchain d7d9f15be205b45d44700e7ac33b4f79b91f9680
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d7d9f15be205b45d44700e7ac33b4f79b91f9680" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] finished tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] tweaked toml for git repo https://github.com/JohnScience/nifti-example written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/JohnScience/nifti-example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d7d9f15be205b45d44700e7ac33b4f79b91f9680" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[ERROR] this task or one of its parent failed!
[ERROR] no output for 300 seconds
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.
[INFO] documenting JohnScience/nifti-example against master#50be22964035027398754e54cd3a497efb00f83e for pr-117450
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJohnScience%2Fnifti-example" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/JohnScience/nifti-example on toolchain 50be22964035027398754e54cd3a497efb00f83e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] finished tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] tweaked toml for git repo https://github.com/JohnScience/nifti-example written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/JohnScience/nifti-example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[ERROR] error running command: no output for 300 seconds
[INFO] documenting JohnScience/nifti-example against master#50be22964035027398754e54cd3a497efb00f83e for pr-117450
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJohnScience%2Fnifti-example" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/JohnScience/nifti-example on toolchain 50be22964035027398754e54cd3a497efb00f83e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] finished tweaking git repo https://github.com/JohnScience/nifti-example
[INFO] tweaked toml for git repo https://github.com/JohnScience/nifti-example written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/JohnScience/nifti-example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "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 nifti v0.14.0
[INFO] [stderr]   Downloaded byteordered v0.5.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1c6d04fd38835ebe45d8d5b6cec42fa1c2b9c44dd0bd066a7f7a955525e28b45
[INFO] running `Command { std: "docker" "start" "-a" "1c6d04fd38835ebe45d8d5b6cec42fa1c2b9c44dd0bd066a7f7a955525e28b45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1c6d04fd38835ebe45d8d5b6cec42fa1c2b9c44dd0bd066a7f7a955525e28b45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1c6d04fd38835ebe45d8d5b6cec42fa1c2b9c44dd0bd066a7f7a955525e28b45", kill_on_drop: false }`
[INFO] [stdout] 1c6d04fd38835ebe45d8d5b6cec42fa1c2b9c44dd0bd066a7f7a955525e28b45
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+50be22964035027398754e54cd3a497efb00f83e" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 921d977ee18c3351ec8cceb92f705ef72e6bfd16bdff68a1016a802115cb135f
[INFO] running `Command { std: "docker" "start" "-a" "921d977ee18c3351ec8cceb92f705ef72e6bfd16bdff68a1016a802115cb135f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.47
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling crossbeam-utils v0.8.12
[INFO] [stderr]    Compiling syn v1.0.103
[INFO] [stderr]    Compiling crossbeam-epoch v0.9.11
[INFO] [stderr]    Compiling rayon-core v1.9.3
[INFO] [stderr]    Compiling rayon v1.5.3
[INFO] [stderr]    Compiling futures-core v0.3.25
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking getrandom v0.2.8
[INFO] [stderr]     Checking byteorder v1.4.3
[INFO] [stderr]     Checking spin v0.9.4
[INFO] [stderr]     Checking futures-sink v0.3.25
[INFO] [stderr]     Checking rawpointer v0.2.1
[INFO] [stderr]     Checking weezl v0.1.7
[INFO] [stderr]     Checking matrixmultiply v0.3.2
[INFO] [stderr]     Checking approx v0.4.0
[INFO] [stderr]     Checking threadpool v1.8.1
[INFO] [stderr]     Checking num-complex v0.4.2
[INFO] [stderr]     Checking nanorand v0.7.0
[INFO] [stderr]     Checking lebe v0.5.2
[INFO] [stderr]     Checking bit_field v0.10.1
[INFO] [stderr]     Checking half v2.1.0
[INFO] [stderr]     Checking byteordered v0.5.0
[INFO] [stderr]     Checking gif v0.11.4
[INFO] [stderr]     Checking scoped_threadpool v0.1.9
[INFO] [stderr]     Checking bytemuck v1.12.2
[INFO] [stderr]     Checking safe-transmute v0.11.2
[INFO] [stderr]     Checking quick-error v2.0.1
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/proc-macro2-1.0.47/src/lib.rs:92:30
[INFO] [stdout]    |
[INFO] [stdout] 92 |     feature(proc_macro_span, proc_macro_span_shrink)
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking ndarray v0.15.6
[INFO] [stderr]     Checking crossbeam-channel v0.5.6
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "921d977ee18c3351ec8cceb92f705ef72e6bfd16bdff68a1016a802115cb135f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "921d977ee18c3351ec8cceb92f705ef72e6bfd16bdff68a1016a802115cb135f", kill_on_drop: false }`
[INFO] [stdout] 921d977ee18c3351ec8cceb92f705ef72e6bfd16bdff68a1016a802115cb135f