[INFO] fetching crate datatest 0.6.3...
[INFO] documenting datatest-0.6.3 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] extracting crate datatest 0.6.3 into /workspace/builds/worker-10/source
[INFO] validating manifest of crates.io crate datatest 0.6.3 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 datatest 0.6.3
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate datatest 0.6.3
[INFO] tweaked toml for crates.io crate datatest 0.6.3 written to /workspace/builds/worker-10/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-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] d8d94036a4f1a812fba0c1d38e70d36d6bb5ed2a7e6ec693feb19dc316274624
[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" "d8d94036a4f1a812fba0c1d38e70d36d6bb5ed2a7e6ec693feb19dc316274624", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d8d94036a4f1a812fba0c1d38e70d36d6bb5ed2a7e6ec693feb19dc316274624", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d8d94036a4f1a812fba0c1d38e70d36d6bb5ed2a7e6ec693feb19dc316274624", kill_on_drop: false }`
[INFO] [stdout] d8d94036a4f1a812fba0c1d38e70d36d6bb5ed2a7e6ec693feb19dc316274624
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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] 90373b9cfd4b1e537e82561589087aac208f795e958da6117a7d4bf5ae8dc052
[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" "90373b9cfd4b1e537e82561589087aac208f795e958da6117a7d4bf5ae8dc052", kill_on_drop: false }`
[INFO] [stderr]    Compiling datatest v0.6.3 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling ctor v0.1.15
[INFO] [stderr]    Compiling datatest-derive v0.6.3
[INFO] [stderr]     Checking serde v1.0.115
[INFO] [stderr]     Checking serde_yaml v0.8.13
[INFO] [stderr]  Documenting datatest v0.6.3 (/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(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(termination_trait_lib)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 4 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 `datatest`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name datatest src/lib.rs -o /opt/rustwide/target/doc --cfg 'feature="default"' --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern ctor=/opt/rustwide/target/debug/deps/libctor-9cb8385ae3413d26.so --extern datatest_derive=/opt/rustwide/target/debug/deps/libdatatest_derive-e2138a7636c06bcd.so --extern regex=/opt/rustwide/target/debug/deps/libregex-5103ea9f59ed634c.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-91aa7737e0991a73.rmeta --extern serde_yaml=/opt/rustwide/target/debug/deps/libserde_yaml-80a2003cf6aba03a.rmeta --extern walkdir=/opt/rustwide/target/debug/deps/libwalkdir-72ead3ebf3ce29a8.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" "90373b9cfd4b1e537e82561589087aac208f795e958da6117a7d4bf5ae8dc052", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "90373b9cfd4b1e537e82561589087aac208f795e958da6117a7d4bf5ae8dc052", kill_on_drop: false }`
[INFO] [stdout] 90373b9cfd4b1e537e82561589087aac208f795e958da6117a7d4bf5ae8dc052