[INFO] fetching crate dbkit-engine 0.0.9...
[INFO] documenting dbkit-engine-0.0.9 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate dbkit-engine 0.0.9 into /workspace/builds/worker-84/source
[INFO] validating manifest of crates.io crate dbkit-engine 0.0.9 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate dbkit-engine 0.0.9
[INFO] finished tweaking crates.io crate dbkit-engine 0.0.9
[INFO] tweaked toml for crates.io crate dbkit-engine 0.0.9 written to /workspace/builds/worker-84/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "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" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rustc-serialize v0.3.24
[INFO] [stderr]   Downloaded toml v0.2.1
[INFO] [stderr]   Downloaded itertools v0.4.19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-84/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-84/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6bb11d67d7de6041dd1b78644401d8d341c9f3f8d8ab5673feb49ce4fd4150f6
[INFO] running `Command { std: "docker" "start" "-a" "6bb11d67d7de6041dd1b78644401d8d341c9f3f8d8ab5673feb49ce4fd4150f6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6bb11d67d7de6041dd1b78644401d8d341c9f3f8d8ab5673feb49ce4fd4150f6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6bb11d67d7de6041dd1b78644401d8d341c9f3f8d8ab5673feb49ce4fd4150f6", kill_on_drop: false }`
[INFO] [stdout] 6bb11d67d7de6041dd1b78644401d8d341c9f3f8d8ab5673feb49ce4fd4150f6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-84/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-84/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c2da4e3805739a30864a3966993f293b6fb24baef0a71711387bb7cd7c6bc588
[INFO] running `Command { std: "docker" "start" "-a" "c2da4e3805739a30864a3966993f293b6fb24baef0a71711387bb7cd7c6bc588", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking rustc-serialize v0.3.24
[INFO] [stderr]     Checking itertools v0.4.19
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]     Checking toml v0.2.1
[INFO] [stderr]  Documenting dbkit-engine v0.0.9 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0432]: unresolved import `alloc::heap`
[INFO] [stdout]  --> src/allocator.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 3 | use alloc::heap;
[INFO] [stdout]   |     ^^^^^^^^^^^ no `heap` in the root
[INFO] [stdout] 
[INFO] [stdout] 
[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(alloc)]
[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(associated_consts)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `associated_consts` has been stable since 1.20.0 and no longer requires an attribute to enable
[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(associated_type_defaults)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(box_patterns)]
[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:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(box_syntax)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(heap_api)]
[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:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(question_mark)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]   |
[INFO] [stdout]   = help: the feature `question_mark` has been stable since 1.13.0 and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not document `dbkit-engine`
[INFO] [stdout] error: aborting due to 9 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] Some errors have detailed explanations: E0432, E0554.
[INFO] [stdout] 
[INFO] [stderr] Caused by:
[INFO] [stdout] For more information about an error, try `rustc --explain E0432`.
[INFO] [stdout] 
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name dbkit_engine src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=f51675247b642817 -L dependency=/opt/rustwide/target/debug/deps --extern itertools=/opt/rustwide/target/debug/deps/libitertools-bef1579a61811a6e.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-53ace35329ab3d63.rmeta --extern toml=/opt/rustwide/target/debug/deps/libtoml-828e67e94f67b6d0.rmeta --cap-lints=warn --crate-version 0.0.9` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "c2da4e3805739a30864a3966993f293b6fb24baef0a71711387bb7cd7c6bc588", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c2da4e3805739a30864a3966993f293b6fb24baef0a71711387bb7cd7c6bc588", kill_on_drop: false }`
[INFO] [stdout] c2da4e3805739a30864a3966993f293b6fb24baef0a71711387bb7cd7c6bc588