[INFO] fetching crate arc_ast 0.1.0...
[INFO] checking arc_ast-0.1.0 against try#15a786332e2f0dd343b226ab6bb8ec028a350f73 for pr-81782
[INFO] extracting crate arc_ast 0.1.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate arc_ast 0.1.0 on toolchain 15a786332e2f0dd343b226ab6bb8ec028a350f73
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate arc_ast 0.1.0
[INFO] finished tweaking crates.io crate arc_ast 0.1.0
[INFO] tweaked toml for crates.io crate arc_ast 0.1.0 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "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-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] f99f7b49f5b05fd038e0a1a3acc1e3ae3787c26b2f7f3105c6c36cb827e46fdf
[INFO] running `Command { std: "docker" "start" "-a" "f99f7b49f5b05fd038e0a1a3acc1e3ae3787c26b2f7f3105c6c36cb827e46fdf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f99f7b49f5b05fd038e0a1a3acc1e3ae3787c26b2f7f3105c6c36cb827e46fdf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f99f7b49f5b05fd038e0a1a3acc1e3ae3787c26b2f7f3105c6c36cb827e46fdf", kill_on_drop: false }`
[INFO] [stdout] f99f7b49f5b05fd038e0a1a3acc1e3ae3787c26b2f7f3105c6c36cb827e46fdf
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "RUSTFLAGS=--cap-lints=forbid" "-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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f9c2f7fd0a066625295e95ec21a8087ae7f343722173c06cc99c908e941d82bf
[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" "f9c2f7fd0a066625295e95ec21a8087ae7f343722173c06cc99c908e941d82bf", kill_on_drop: false }`
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]     Checking arc_number v0.1.1
[INFO] [stderr]     Checking arc_ast v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `ops::IndexMut`
[INFO] [stdout]  --> src/utils/ast_impl.rs:4:34
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::{collections::VecDeque, ops::IndexMut};
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Error`
[INFO] [stdout]  --> src/utils/ast_traits.rs:4:33
[INFO] [stdout]   |
[INFO] [stdout] 4 |     fmt::{self, Debug, Display, Error, Formatter},
[INFO] [stdout]   |                                 ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::VecDeque`
[INFO] [stdout]  --> src/lib.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use std::collections::VecDeque;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ops::IndexMut`
[INFO] [stdout]  --> src/utils/ast_impl.rs:4:34
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::{collections::VecDeque, ops::IndexMut};
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Error`
[INFO] [stdout]  --> src/utils/ast_traits.rs:4:33
[INFO] [stdout]   |
[INFO] [stdout] 4 |     fmt::{self, Debug, Display, Error, Formatter},
[INFO] [stdout]   |                                 ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::collections::VecDeque`
[INFO] [stdout]  --> src/lib.rs:9:5
[INFO] [stdout]   |
[INFO] [stdout] 9 | use std::collections::VecDeque;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `length` is assigned to, but never used
[INFO] [stdout]   --> src/utils/ast_traits.rs:71:21
[INFO] [stdout]    |
[INFO] [stdout] 71 |                 let mut length = 0;
[INFO] [stdout]    |                     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: consider using `_length` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `length` is assigned to, but never used
[INFO] [stdout]   --> src/utils/ast_traits.rs:71:21
[INFO] [stdout]    |
[INFO] [stdout] 71 |                 let mut length = 0;
[INFO] [stdout]    |                     ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: consider using `_length` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.44s
[INFO] running `Command { std: "docker" "inspect" "f9c2f7fd0a066625295e95ec21a8087ae7f343722173c06cc99c908e941d82bf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f9c2f7fd0a066625295e95ec21a8087ae7f343722173c06cc99c908e941d82bf", kill_on_drop: false }`
[INFO] [stdout] f9c2f7fd0a066625295e95ec21a8087ae7f343722173c06cc99c908e941d82bf