[INFO] fetching crate aces 0.0.13...
[INFO] documenting aces-0.0.13 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate aces 0.0.13 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate aces 0.0.13 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 crates.io crate aces 0.0.13
[INFO] finished tweaking crates.io crate aces 0.0.13
[INFO] tweaked toml for crates.io crate aces 0.0.13 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] [stdout] b84252fcf7122330069bfcc7c9bc1fe584769fcb5799f86f3a8a2f10684c96d7
[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" "b84252fcf7122330069bfcc7c9bc1fe584769fcb5799f86f3a8a2f10684c96d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b84252fcf7122330069bfcc7c9bc1fe584769fcb5799f86f3a8a2f10684c96d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b84252fcf7122330069bfcc7c9bc1fe584769fcb5799f86f3a8a2f10684c96d7", kill_on_drop: false }`
[INFO] [stdout] b84252fcf7122330069bfcc7c9bc1fe584769fcb5799f86f3a8a2f10684c96d7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] db95d78c9c68ae6b337eb43739b093d658841d8ff29e0cca1d777cd22c1d1cb0
[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" "db95d78c9c68ae6b337eb43739b093d658841d8ff29e0cca1d777cd22c1d1cb0", kill_on_drop: false }`
[INFO] [stderr]     Checking varisat-formula v0.2.1
[INFO] [stderr]     Checking siphasher v0.3.3
[INFO] [stderr]     Checking hashbrown v0.3.1
[INFO] [stderr]     Checking leb128 v0.2.4
[INFO] [stderr]     Checking vec_mut_scan v0.1.0
[INFO] [stderr]     Checking precomputed-hash v0.1.1
[INFO] [stderr]     Checking new_debug_unreachable v1.0.4
[INFO] [stderr]     Checking bit-vec v0.6.2
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]     Checking colored v1.9.3
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]    Compiling varisat v0.2.1
[INFO] [stderr]    Compiling synstructure v0.10.2
[INFO] [stderr]    Compiling partial_ref_derive v0.3.1
[INFO] [stderr]     Checking fern v0.6.0
[INFO] [stderr]     Checking varisat-dimacs v0.2.1
[INFO] [stderr]     Checking varisat-internal-proof v0.2.1
[INFO] [stderr]     Checking phf_shared v0.8.0
[INFO] [stderr]     Checking string_cache v0.8.0
[INFO] [stderr]     Checking varisat-checker v0.2.1
[INFO] [stderr]    Compiling varisat-internal-macros v0.2.1
[INFO] [stderr]     Checking partial_ref v0.3.1
[INFO] [stderr]     Checking ordered-float v1.1.0
[INFO] [stderr]  Documenting aces v0.0.13 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(bool_to_option)]
[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 `aces`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name aces src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern bit_vec=/opt/rustwide/target/debug/deps/libbit_vec-90817b2e61215164.rmeta --extern fern=/opt/rustwide/target/debug/deps/libfern-e652c85a7ee64c4e.rmeta --extern lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-57a7edc7f441d44c.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-958bf2a074a4960f.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-d97dfd4fcccce7fb.rmeta --extern regex=/opt/rustwide/target/debug/deps/libregex-5103ea9f59ed634c.rmeta --extern string_cache=/opt/rustwide/target/debug/deps/libstring_cache-062ddb6dda90ccff.rmeta --extern varisat=/opt/rustwide/target/debug/deps/libvarisat-490fd04fbd9c8d27.rmeta --extern yaml_rust=/opt/rustwide/target/debug/deps/libyaml_rust-d4c35ebea6d80308.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "db95d78c9c68ae6b337eb43739b093d658841d8ff29e0cca1d777cd22c1d1cb0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db95d78c9c68ae6b337eb43739b093d658841d8ff29e0cca1d777cd22c1d1cb0", kill_on_drop: false }`
[INFO] [stdout] db95d78c9c68ae6b337eb43739b093d658841d8ff29e0cca1d777cd22c1d1cb0