[INFO] cloning repository https://github.com/joel-simon/fastaq_ngrams
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/joel-simon/fastaq_ngrams" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoel-simon%2Ffastaq_ngrams", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoel-simon%2Ffastaq_ngrams'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a3ba5361c8320b635d19769cea948b117a0beb56
[INFO] documenting joel-simon/fastaq_ngrams against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjoel-simon%2Ffastaq_ngrams" "/workspace/builds/worker-13/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/joel-simon/fastaq_ngrams on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/joel-simon/fastaq_ngrams
[INFO] finished tweaking git repo https://github.com/joel-simon/fastaq_ngrams
[INFO] tweaked toml for git repo https://github.com/joel-simon/fastaq_ngrams written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/joel-simon/fastaq_ngrams already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--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-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 72ec70fa500d7807508a0faccce66b5e8055a09487f94fb6c06b85302beea947
[INFO] running `Command { std: "docker" "start" "-a" "72ec70fa500d7807508a0faccce66b5e8055a09487f94fb6c06b85302beea947", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "72ec70fa500d7807508a0faccce66b5e8055a09487f94fb6c06b85302beea947", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "72ec70fa500d7807508a0faccce66b5e8055a09487f94fb6c06b85302beea947", kill_on_drop: false }`
[INFO] [stdout] 72ec70fa500d7807508a0faccce66b5e8055a09487f94fb6c06b85302beea947
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] eada153f99149e7f44f19746165629e7189e560c477d5ed842989958b2ffbae9
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "eada153f99149e7f44f19746165629e7189e560c477d5ed842989958b2ffbae9", kill_on_drop: false }`
[INFO] [stderr]  Documenting seq_cluster v0.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `std::old_io`
[INFO] [stdout]  --> src/main.rs:2:10
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::old_io::File;
[INFO] [stdout]   |          ^^^^^^ could not find `old_io` in `std`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `seq_cluster`.
[INFO] [stdout] error[E0432]: unresolved import `std::old_io`
[INFO] [stdout]  --> src/main.rs:4:10
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::old_io::BufferedReader;
[INFO] [stdout]   |          ^^^^^^ could not find `old_io` in `std`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[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(collections,path,io,core)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] Caused by:
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type bin --crate-name seq_cluster src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --cap-lints=warn` (exit code: 1)
[INFO] [stdout] error: aborting due to 4 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0554.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "eada153f99149e7f44f19746165629e7189e560c477d5ed842989958b2ffbae9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "eada153f99149e7f44f19746165629e7189e560c477d5ed842989958b2ffbae9", kill_on_drop: false }`
[INFO] [stdout] eada153f99149e7f44f19746165629e7189e560c477d5ed842989958b2ffbae9