[INFO] fetching crate teatree 0.0.4...
[INFO] documenting teatree-0.0.4 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate teatree 0.0.4 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate teatree 0.0.4 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate teatree 0.0.4
[INFO] finished tweaking crates.io crate teatree 0.0.4
[INFO] tweaked toml for crates.io crate teatree 0.0.4 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4b80b5d5db533d0a95e0697e61476c5507f9c45bc9613a6b20ef3cafc306791c
[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" "4b80b5d5db533d0a95e0697e61476c5507f9c45bc9613a6b20ef3cafc306791c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4b80b5d5db533d0a95e0697e61476c5507f9c45bc9613a6b20ef3cafc306791c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4b80b5d5db533d0a95e0697e61476c5507f9c45bc9613a6b20ef3cafc306791c", kill_on_drop: false }`
[INFO] [stdout] 4b80b5d5db533d0a95e0697e61476c5507f9c45bc9613a6b20ef3cafc306791c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1b4703cd2fc072dd2ab0858b70740171fb8622ab872bc07d882c20e18d9cc055
[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" "1b4703cd2fc072dd2ab0858b70740171fb8622ab872bc07d882c20e18d9cc055", kill_on_drop: false }`
[INFO] [stderr]     Checking actix-service v0.4.2
[INFO] [stderr]     Checking lock_api v0.2.0
[INFO] [stderr]     Checking fxhash v0.2.1
[INFO] [stderr]     Checking bytes v0.4.12
[INFO] [stderr]    Compiling enum-as-inner v0.2.1
[INFO] [stderr]    Compiling derive_more v0.15.0
[INFO] [stderr]    Compiling actix_derive v0.4.0
[INFO] [stderr]    Compiling derive_more v0.14.1
[INFO] [stderr]     Checking ahash v0.2.19
[INFO] [stderr]     Checking sha3 v0.7.3
[INFO] [stderr]     Checking parking_lot_core v0.5.0
[INFO] [stderr]     Checking curve25519-dalek v3.0.0
[INFO] [stderr]     Checking hashbrown v0.3.1
[INFO] [stderr]     Checking bincode v1.3.1
[INFO] [stderr]     Checking serde_urlencoded v0.6.1
[INFO] [stderr]     Checking serde_bytes v0.11.5
[INFO] [stderr]     Checking ed25519 v1.0.3
[INFO] [stderr]     Checking parking_lot v0.8.0
[INFO] [stderr]     Checking hashbrown v0.6.3
[INFO] [stderr]     Checking tokio-io v0.1.13
[INFO] [stderr]     Checking http v0.1.21
[INFO] [stderr]     Checking string v0.2.1
[INFO] [stderr]     Checking ed25519-dalek v1.0.1
[INFO] [stderr]     Checking tokio-reactor v0.1.12
[INFO] [stderr]     Checking tokio-codec v0.1.2
[INFO] [stderr]     Checking tokio-fs v0.1.7
[INFO] [stderr]     Checking pagecache v0.17.0
[INFO] [stderr]     Checking actix-codec v0.1.2
[INFO] [stderr]     Checking tokio-tcp v0.1.4
[INFO] [stderr]     Checking tokio-udp v0.1.6
[INFO] [stderr]     Checking tokio-uds v0.2.7
[INFO] [stderr]     Checking actix-server-config v0.1.2
[INFO] [stderr]     Checking actix-utils v0.4.7
[INFO] [stderr]     Checking tokio v0.1.22
[INFO] [stderr]     Checking trust-dns-proto v0.7.4
[INFO] [stderr]     Checking h2 v0.1.26
[INFO] [stderr]     Checking jsonrpc-parse v0.1.2
[INFO] [stderr]     Checking trust-dns-resolver v0.11.1
[INFO] [stderr]     Checking sled v0.24.1
[INFO] [stderr]     Checking actix-threadpool v0.1.2
[INFO] [stderr]     Checking actix-rt v0.2.6
[INFO] [stderr]     Checking actix-connect v0.2.5
[INFO] [stderr]     Checking actix-http v0.2.11
[INFO] [stderr]     Checking actix v0.8.3
[INFO] [stderr]  Documenting teatree v0.0.4 (/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(vec_drain_as_slice)]
[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 `teatree`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name teatree 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 actix=/opt/rustwide/target/debug/deps/libactix-8cb45ba199583541.rmeta --extern actix_derive=/opt/rustwide/target/debug/deps/libactix_derive-09d5f9eff399babc.so --extern bincode=/opt/rustwide/target/debug/deps/libbincode-dcf2caaa2e2215bb.rmeta --extern byteorder=/opt/rustwide/target/debug/deps/libbyteorder-f694b9af15911675.rmeta --extern bytes=/opt/rustwide/target/debug/deps/libbytes-1f2435b202ac1ada.rmeta --extern dirs=/opt/rustwide/target/debug/deps/libdirs-635bbce02d703ffa.rmeta --extern ed25519_dalek=/opt/rustwide/target/debug/deps/libed25519_dalek-f499811f7c8f968a.rmeta --extern failure=/opt/rustwide/target/debug/deps/libfailure-fa85c9e222265e84.rmeta --extern futures=/opt/rustwide/target/debug/deps/libfutures-2f80a151d70e23d0.rmeta --extern jsonrpc_parse=/opt/rustwide/target/debug/deps/libjsonrpc_parse-6625e35448315257.rmeta --extern rand=/opt/rustwide/target/debug/deps/librand-a439fa47bb68366e.rmeta --extern serde=/opt/rustwide/target/debug/deps/libserde-ce360c6747a68ca1.rmeta --extern serde_derive=/opt/rustwide/target/debug/deps/libserde_derive-cd17107806a312ab.so --extern serde_json=/opt/rustwide/target/debug/deps/libserde_json-a547664976a3b244.rmeta --extern sha3=/opt/rustwide/target/debug/deps/libsha3-6659d426095ae773.rmeta --extern sled=/opt/rustwide/target/debug/deps/libsled-8e07cb29b0b34e80.rmeta --extern tokio=/opt/rustwide/target/debug/deps/libtokio-8298c491719b710e.rmeta --extern toml=/opt/rustwide/target/debug/deps/libtoml-5df166504bf2f6fb.rmeta --cap-lints=warn --crate-version 0.0.4` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "1b4703cd2fc072dd2ab0858b70740171fb8622ab872bc07d882c20e18d9cc055", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1b4703cd2fc072dd2ab0858b70740171fb8622ab872bc07d882c20e18d9cc055", kill_on_drop: false }`
[INFO] [stdout] 1b4703cd2fc072dd2ab0858b70740171fb8622ab872bc07d882c20e18d9cc055
