[INFO] cloning repository https://github.com/vramana/merkle-rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/vramana/merkle-rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvramana%2Fmerkle-rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvramana%2Fmerkle-rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] b8a1cf42e1647437f447969e2ce79cd8b327fe2f
[INFO] documenting vramana/merkle-rs against beta-2020-08-29 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvramana%2Fmerkle-rs" "/workspace/builds/worker-12/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-12/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/vramana/merkle-rs on toolchain beta-2020-08-29
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/vramana/merkle-rs
[INFO] finished tweaking git repo https://github.com/vramana/merkle-rs
[INFO] tweaked toml for git repo https://github.com/vramana/merkle-rs written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate git repo https://github.com/vramana/merkle-rs already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-08-29" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+beta-2020-08-29" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 746c35b7f69fdbda27fc188ac7d3bb5ef02dd950e2b720fb9d374455d4626b10
[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" "746c35b7f69fdbda27fc188ac7d3bb5ef02dd950e2b720fb9d374455d4626b10", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "746c35b7f69fdbda27fc188ac7d3bb5ef02dd950e2b720fb9d374455d4626b10", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "746c35b7f69fdbda27fc188ac7d3bb5ef02dd950e2b720fb9d374455d4626b10", kill_on_drop: false }`
[INFO] [stdout] 746c35b7f69fdbda27fc188ac7d3bb5ef02dd950e2b720fb9d374455d4626b10
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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" "+beta-2020-08-29" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d36ed20406e4f59df286d20b83e484b7e8078fde265adc5055db6aa0e14b25fc
[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" "d36ed20406e4f59df286d20b83e484b7e8078fde265adc5055db6aa0e14b25fc", kill_on_drop: false }`
[INFO] [stderr]     Checking cpuid-bool v0.1.0
[INFO] [stderr]    Compiling generic-array v0.14.2
[INFO] [stderr]     Checking block-buffer v0.9.0
[INFO] [stderr]     Checking digest v0.9.0
[INFO] [stderr]     Checking sha2 v0.9.1
[INFO] [stderr]  Documenting merkle-rs v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: expected one of `::`, `;`, or `as`, found keyword `use`
[INFO] [stdout]  --> src/main.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | use digest::Digest
[INFO] [stdout]   |                   - expected one of `::`, `;`, or `as`
[INFO] [stdout] 5 | use sha2::Sha256;
[INFO] [stdout]   | ^^^ unexpected token
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `merkle-rs`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name merkle_rs 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 --extern digest=/opt/rustwide/target/debug/deps/libdigest-71c6ca43f071b0d8.rmeta --extern sha2=/opt/rustwide/target/debug/deps/libsha2-0dadce0f0dff72b6.rmeta --cap-lints=warn --crate-version 0.1.0` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "d36ed20406e4f59df286d20b83e484b7e8078fde265adc5055db6aa0e14b25fc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d36ed20406e4f59df286d20b83e484b7e8078fde265adc5055db6aa0e14b25fc", kill_on_drop: false }`
[INFO] [stdout] d36ed20406e4f59df286d20b83e484b7e8078fde265adc5055db6aa0e14b25fc