[INFO] fetching crate compact 0.2.16...
[INFO] documenting compact-0.2.16 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate compact 0.2.16 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate compact 0.2.16 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 compact 0.2.16
[INFO] finished tweaking crates.io crate compact 0.2.16
[INFO] tweaked toml for crates.io crate compact 0.2.16 written to /workspace/builds/worker-7/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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 48e2b9b6946650cf3357e2e4a5b859243071c00a19cddd8341e1d4d272e89007
[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" "48e2b9b6946650cf3357e2e4a5b859243071c00a19cddd8341e1d4d272e89007", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "48e2b9b6946650cf3357e2e4a5b859243071c00a19cddd8341e1d4d272e89007", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "48e2b9b6946650cf3357e2e4a5b859243071c00a19cddd8341e1d4d272e89007", kill_on_drop: false }`
[INFO] [stdout] 48e2b9b6946650cf3357e2e4a5b859243071c00a19cddd8341e1d4d272e89007
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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] 060b876e3166513211bb46997ff6c6467a3e4cb0a7fab93e73768a55cd2e6c7d
[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" "060b876e3166513211bb46997ff6c6467a3e4cb0a7fab93e73768a55cd2e6c7d", kill_on_drop: false }`
[INFO] [stderr]     Checking hamming v0.1.3
[INFO] [stderr]     Checking primal-estimate v0.2.1
[INFO] [stderr]     Checking simple_allocator_trait v0.1.0
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]     Checking primal-bit v0.2.4
[INFO] [stderr]     Checking primal-sieve v0.2.9
[INFO] [stderr]     Checking num-integer v0.1.43
[INFO] [stderr]     Checking primal-check v0.2.3
[INFO] [stderr]     Checking primal v0.2.3
[INFO] [stderr]  Documenting compact v0.2.16 (/opt/rustwide/workdir)
[INFO] [stderr] error: Could not document `compact`.
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | #![feature(specialization)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] Caused by:
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name compact 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 lazy_static=/opt/rustwide/target/debug/deps/liblazy_static-57a7edc7f441d44c.rmeta --extern primal=/opt/rustwide/target/debug/deps/libprimal-3e2e14b60f0b6e78.rmeta --extern simple_allocator_trait=/opt/rustwide/target/debug/deps/libsimple_allocator_trait-efa78448b4da1614.rmeta --cap-lints=warn` (exit code: 1)
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "060b876e3166513211bb46997ff6c6467a3e4cb0a7fab93e73768a55cd2e6c7d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "060b876e3166513211bb46997ff6c6467a3e4cb0a7fab93e73768a55cd2e6c7d", kill_on_drop: false }`
[INFO] [stdout] 060b876e3166513211bb46997ff6c6467a3e4cb0a7fab93e73768a55cd2e6c7d